PNO-V-86-082, on 861117,water Observed Leaking from Spent Fuel Pool Liner Into Annulus,Through Concrete Walls Into Nonradiologically Controlled Part of Plant.Caused by Annulus Drain Valve Closed for Maint.Annulus Area Drained

PNO-V-86-082:on 861117,water Observed Leaking from Spent Fuel Pool Liner Into Annulus,Through Concrete Walls Into Nonradiologically Controlled Part of Plant.Caused by Annulus Drain Valve Closed for Maint.Annulus Area Drained

ML20214F469
Person / Time
Site:	Rancho Seco
Issue date:	11/18/1986
From:	Miller L, Perez G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
To:
References
PNO-V-86-082, PNO-V-86-82, NUDOCS 8611250315
Download: ML20214F469 (2)

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h r PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE-PNO-V-86-82 Dato: 11/18/86 V _

i

' ' This preliminary notification constitutes EARLY notice .of events of POSSIBLE safety or '

.public interest significance. The information presented is as initially received without

' verification or evaluation and is basically all that is known by Region V staff on this dste.

FACILITY: Sacramento Municipal Utility District Emergency Classification Rancho Seco Nuclear Power Plant Notification of Unusual Event Sacramento County, California Alert Docket No. 50-312 Site Area Emergency General Emergency X Not Applicable

SUBJECT:

POTENTIAL UNCONTROLLED RADIOACTIVE LEAKAGE FROM SPENT FUEL POOL On November 17, 1986, the licensee made a report, pursuant to 10CFR50.72(b),(2)(iii)(C),

of an event that could have prevented control of the release of radioactive material.

Spscifically, water was observed leaking from the SFP liner into the annulus, then thru th2 concreta walls of the fuel handling building into the non-radiologically controlled partion of-the plant. This condition has been observed in the past but does not normally rssult in a potential release to the environment, since the annulus'is drained to the 4

racctor coolant drain tank.

In this instance the annulus drain valve was closed for maintenance activities allowing water to accumulate in the annulus. The accumulated water is conjectured to have

,psrmeated the concrete structure, such that the exterior surface of the fuel handling building had levels of surface contamination of 2000 or 3000 disintegrations per minute

par 100 cua .' A small trickle of liquid accumulated on the pavement adjoining the area and-

',.spproximately one' gallon has been estimated to have flowed into a yard drain that goes

'-off-site. >The activity of the water was measured at IE-5 uCi/ml.

Tha licensee took measures to contain the liquid and drained the annulus area which j ctcpped leakage from the fuel handling building. The 10CFR part 20 and Technical Sp:cification liquid effluent release limits were_not approached or exceeded. The

, > < licensee and resident. inspectors continue to evaluate this matter.

This information is-current as of 10:00 am PST, November 18, 1986.

, r CONTACT: G. Perez L. Miller, Jr.

(209) 748-2791 FTS 463-3869 6

! DISTRIBUTION H St. MNBBSN Phillips E/W Willste Air Rights5 Mail:

Chairman Zech EDO NRR IE NMSS ADM:DMB Comm. Bernthal PA OIA RES DOT:Trans Only i Comm. Roberts MPA AEOD Comm. Asselstine 'OGC 2 Comm. Carr Regions:

.SECY INPO f*SO NSAC 3: 53 ACRS Licensee: 2*' T 7

-CA (Reactor Licensees) REGION V: FORM 211-PDR Resident Inspector (Revised 3/14/83)

HQS OfaMTW 5NTd Y 86112S0315 861110  ;

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