ML20126H331

RO 2-81-22/1P:on 810331 During Feed & Bleed Operation, Drywell Chilled Water Closed Cooling Sys Inadvertently Drained to Normal Waste Drain Sys.Release Terminated Upon Discovery.Further Investigation Planned

ML20126H331
Person / Time
Site:	Peach Bottom
Issue date:	04/01/1981
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
RO-2-81-22-1P, NUDOCS 8104090297
Download: ML20126H331 (2)

Text

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_ LPD R pullmetenth unacraic conPAur Peach Bottcm Atonio Power $tation Delta, Pennsylvania **

17314 April 1. 1981 Mr. boyce H. Grier k Office of Inspection and Enforcement- [

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Region I l United states Nuclear segulatory comaniesion t

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King of Prussia, PA 19406.

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sulA2cer REPOR7AB12 OCCURRENCE - PROMPT NOTIFICA'r10N %p; g)g Confirming k. 8. Fleischmann's conversation with Mr. C. Cowgill, Aegion Nuclear Regulatory Commission Office of Inspection and unforcement on March 31, 1981.

References Docket No. 50-277 Peach Bottosa Unit 2 Technical specification meterences 3.3.3.4 Report Ho, 2-81-22/IP -

Docurrence Date: 3/31/81 Identification of Occurrences . .' . h Unmonitored radioactive release. l Conditions Prior to Oecurrences Unit 2 operating at 100% power.

Apparent cause of occurrencee During a " feed and bleed" operation on the dresell chilled water closed cooling system to reduce the radioactive invsntory, the system was inadvertently drained to a normal waste drain system which discharges to the discharge canal via the storm drain system. '

Analysis ___of Oecurrence:

Initiation of the " feed and bleed" began at hbout 6:00~PM on 3/30/81. At approximately 11:00 AM on 3/31/81, it was discovered that the system was being drained to normal waste. Draining was immediately terminated, sgpropriate etspling and investigation of the occurrence was initiated. Later in the day, a saml1 leak irom a chemical addition tank in the system was found also going to the normal waste drain system. This too was terminated. Based on samples of the drywell chilled water system both before and during the " feed and bleed

• operation, it was estimated that approminately 200 uC1 were released. We major isotopes released were Na-24 and Cr-51 with traoos of I-133. he average concentratii t)1007

.5 8104090 @ /o S

during the release is estimated to be approuimately 2.5 times spo. Total estiinated release is 625 gallons over a period of 17 houra. This release was diluted in tbs discharge canal by a circulating water flow of one million gallons per soinute resu1ng in a dilution factor in excess of one million. Samples taken in the storm drain system following termination revealed no activity. Due to the very high dilution f actor, the environmental significance is minimal. Corrective Actions

!                                  The relea6e was terminated upon discovery. " Food and bleed

• operations will i

not be conducted in the future without clear procedural control. Further investigation of the normal waats drain system is planned. Previoun occurrence,s Report.No. 2-90-10/IP. Very truly yours, gg' _. W. T. Ullrich Statices Super!ntendent Wry / REP 11h l{ t 0 4 4 $%%%%%%% c.,-,v-.. - . - -.,- . , .-.s, ,.,.,%..,..._,,,,,,_.,,,m_ , _ , . . . _ _ _ . , , _ _}}