ML20062D610

RO:1982 Second Quarter Liquid Radwaste Discharges Were 9.94 Ci,Exceeding Ets.Caused by Steam Generator Primary Side to Secondary Side Leakage & Increased Activity in Rcs,Due to Degraded Fuel Performance.Demineralizer Effluent Monitored

ML20062D610
Person / Time
Site:	Millstone
Issue date:	07/29/1982
From:	Mroczka E NORTHEAST NUCLEAR ENERGY CO.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
MP-2-5259, NUDOCS 8208060166
Download: ML20062D610 (3)

Text

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NORTHEAST IRII.ITIES w ,x.r.o m euw w. c"" P.O. BOX 270 UUSSuTINN NeYcUw, HARTFORD. CONNECTICUT 06101 L L T; $h5d3,357blll July 29, 1982 MP-2-5259 Mr. Ronald C. Haynes Regional Administrator, Region 1 Office of Inspection and Enforcement U. S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, Pennsylvania 19406

References:

(1) Facility Operating License DPR-65 Docket No. 50-336 (2) Report # ETS-NR/50-245/50-336/82 May 6, 1982 (3) Report # ETS-NR/50-245/50-336/82 June 3, 1982

Dear Mr. Haynes:

This letter forwards the 30 day report required to be submitted pursuant to Millstone Unit 2 Appendix B Environmental Technical Specifications, Section 5.6.2.a.(2). The report concerns liquid waste discharge exceeding 2.5 Ci/

reactor / calendar quarter per Specification 2.4.1.2.c as was in effect until May 28,1982.

Yours truly, NORTHEAST NUCLEAR ENERGY COMPANY o'

/f,H< ;!a/

. J. Mroczka Station Superintendent Millstone Nuclear Power Station EJM/SLS:mo Attachment cc: Director, Office of Inspection and Enforcement, Washington, D. C. (20)

Director, Office of Management Information and Program Control, Washington, D. C. (2)

Director, Division of Reactor Licensing kft N O s

ss

i Event

Description:

1982 second quarter liquid radwaste discharges were 9.94 curies. Environmental Technical Specifications (ETS) 2.4.1.2.B require that "the equipment installed in the liquid waste system shall be maintained and shall be operated to process radioactive liquid waste prior to their discharge when the projected cumulative release could exceed 1.25 Ci/ reactor / calendar quarter, excluding tritium and dissolved gases". During the time period start-ing on April 1,1982 until the end of the calendar quarter this requirement was met. Also ETS 2.4.1.2.c states "if the cumulative release of radioactive materials in liquid effluents excluding tritium and dissolved gases, exceeds 2.5 Ci/ reactor / calendar quarter, the licensee shall make an investigation to identify the cause of such releases, define and initiate a program of action to reduce such releases to design objective levels and report these actions to the commission within 30 days from the end of the quarter during which the re-lease occurred". The recently revised Environmental Technical Specification would not require a 30 day report for this discharge level, however since the 2.5 curie limit was exceeded prior to the ETS revision this report is being written and it's submittal satisfies this requirement.

Cause and Corrective Action: The cause of the increased liquid radwaste dis-charge was determined to be steam generator primary side to secondary side leakage and increased activity in the Reactor Coolant System due to degraded fuel performance. This was confirmed by continued high activity indicated by the Steam Jet Air Ejector radiation monitor. During this time period the radio-active discharges were monitored in accordance with Technical Specification requirements and a majority of the discharges were attributable to the Steam Generator Blowdown. During this quarter a Steam Generator Blowdown Treatment System was constructed and went into operation on June 11, 1982. The system removed all radiological activity from the blowdown water with the exception of dissolved gases, until the end of the quarter, and remains in operation.

All liquid discharged from the blowdown tank and blowdown quench tank is pumped thru the treatment system demineralizers prior to being released to the environ-ment. Demineralizer effluent is continuously monitored for radiological activity in addition to the daily blowdown and demineralizer grab samples.

Effect of Increased Discharge Levels: Offsite doses from Millstone Unit 2 liquid effluent were calculated and are tabulated on Table I. The calculated offsite doses, while greater than typical quarterly liquid doses from Unit 2, are well within all applicable limits and 10CFR50, Appendix I, design guidelines and hence result in no measurable effects on health or safety of the general public.

In actuality the doses are well within the bases for the 2.5 Curie Limit which is applicable to sites with drinking water pathways.

In addition to the calculation of offsite doses based on measured releases, dose evaluations are made based on measured levels of radioactivity in environmental media. During the second quarter of 1982, plant related radioactivity was detected in aquatic flora and oysters from within 500 feet of the discharge and in fish taken from the quarry. The measured levels in these samples have already been reported to the NRC in Reference 2 and 3. Based on the measured levels in the fish and oysters, the maximum individual dose for the second quarter was calculated to be 0.0007 mrem to the adult whole body and 0.3 mrem to the adult thyroid. These values confirm the realtive accuracy and general conservatism of the doses presented in Table 1.

9 TABLE 1 Millstone 2 Liquid Doses for the Second Quarter 1982 Units April-June 1982 Maximum Individual Dose

a. Whole Body (teen) mrem 0.0084

'b. Maximum Organ (adult thyroid) mrem .0.36 Population Dose (0-50 miles)-

, a. Whole Body person-rem 0.065

b. Maximum Organ (thyroid) person-rem 1.4 l

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