ML20004C364

Forwards LER 81-022/03L-0.Detailed Event Analysis Encl

ML20004C364
Person / Time
Site:	Fort Saint Vrain
Issue date:	04/09/1981
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20004C365	List: ML20004C364 ML20004C366
References
P-81119, NUDOCS 8106030260
Download: ML20004C364 (5)

Text

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PLATTEVILLE. COLOR ADO 80651 d% d.lP7 April 9, 1981 /N h.

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& Y Mr. Karl V. Seyfrit, Director Nuclear Regulatory Cocunission 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

Dear Mr. Seyfrit:

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

81-022, 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. 50-267/81-022.

Very truly yours, 5

Don Warembourg &

Manager, Nuclear Production DW/cls Enclosure

/ o03 cc: Director, MIPC /J l

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REPORT DATE: Aoril 9,1981 ' REPORTABLE OCCURRENCE 81-022 Determined ISSUE O CCCURRENCE DATE: Narch 10, 1981 Page 1 of 4 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO 16805 WELO COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT NO. 50-267/81-022/03-L-0 Final IDENTIFICATION OF CCCURRENCE:

On March 10, 1981, it was determined that the total dissolved solids in the plant non-radioactive liquid effluent exceeded 2300 parts per million on February 24, 1981. This is reportable per Fort St. -Vrain Technical Specification AC 7.5.2(b)2 as a degraded mode of LCO NR 1.1.

EVENT '

DESCRIPTION:

On several previous occasions, the non-radioactive liquid effluent has exceeded the LCO NR 1.1 limit for residual chlorine. These events were reported in Reportable Occurrences 79-61, 80-28, and 81-004 Because of the difficulty in obtaining the exact chlorination required by the system, plant operations hale been modified to include closing the blowdown discharge valve Q1 (see Figure 1) from the circulating water system during chlorination to prevent inadvertent discharge of any high residual chlorine to the Goosequill ditch. To maintain minimum blowdown r te requiremetns during the chlorination, the raw water bypass valve 2 was opened to make up the lost flow.

On Friday, February 20, 1981, this was done during the regular chlorination of the circulating water system; however, following the chlorination, the blowdown d.. charge valve ( was not re-opened.

This resulted in the continued concentration})of total dissolved solids in the circulating water system due to evaporation. The circulating water system was sampled Tuesday, February 24, 1931, and the tolal dissolved solids were found to be high. The biowdown valve Q1 was fully opened, and the blowdown of the circulating water system continued at this rate for aperoximatley two hours when it was noted that the Goosecuill total dissolved solids was 3175 parts per million was in excess of the LCO NR 1.1 limit of 2300 parts per million. The blowdown rate was adjusted to reduce tne total dissolved solids being discharged to the plant effluent and the i liquid effluent was within required chemical limits by the next l shift. The blowdown was continued and has maintained the total j dissolved solids within acceptable limits. The water discharged to l the Goosequill ditch during this event followed the regular discharge P00R ORIGINAll

O REPORTABLE OCCURRENCE 81-022 ISSUE O Page 2 of 4 path from the Goosequill ditch to the farm ponds. The farm pond level was low and it appears unlikely any of this water wb*.

discharged to the South Platte River.

CAUSE DESCRIPTION:

High total dissolved solids in the plant non-radioactive liquid effluent was the result of two problems:

1. Excessive build-up of total dissolved solids in the circulating water system between February 20 and 24, 1981, due to no system blowdown during this period.

2. The following blowdown of the systems on Tuesday, February 24, 1981, at a rate greater than the dilution capability of the Goosequill ditch flow.

CORRECTIVE ACTION:

Circulating water system blowdown was ad, justed to a lower rate, and the total dissolved solids returned to acceptable values by the time of the next sample.

This occurrence will be reviewed by the Plant Review Panel to determine the need for further corrective action in terms of the procedures and individuals involved.

No further corrective action is anticipated or required.

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P00R ORIGINAL

REPORTABLE OCCURRLNCE 81-022 ISSUE O Page 3 of 4 Circulating Water Cold Side Blowdown V-41277 Circulating Water Main Cooling Tower Blowdown to Yard Drain y,41279 y_41273 g lf C O I Circulating Water Hot Side Blowdown Ran Water Bypass h to !!ain Cooling Tower Blowdown E C Circulating Water !!ain Cooling Tower Makeup Supply FIGURE 1

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' REPORTABLE OCCURRENCE 81-022 l ISSUE O j Page 4 of 4 Prepared By: /I' Asa B. Reed Technical Services Tecnnician

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Reviewed By: /

. y Yahm ecnnical Services Supervisor Reviewed By: Y d 8/17 Frank M. Ma nie #/

Operations Manager Appr . .ed . / Y My Lor Waremocurg Mana5J.*, Nuclear Production I

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