ML20210B275

Ro:Holes Found in Aluminum Reactor Tank Line.Cause Unknown. Operations Suspended Until Extent of Problem & Solution Determined.Proposed Actions to Correct Problem Will Be Submitted Prior to Resuming Operations

ML20210B275
Person / Time
Site:	U.S. Geological Survey
Issue date:	03/18/1987
From:	Rusling D INTERIOR, DEPT. OF, GEOLOGICAL SURVEY
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML20210B248	List: ML20210B244 ML20210B275
References
CAL-87-05, CAL-87-5, NUDOCS 8705050277
Download: ML20210B275 (1)

Text

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- United States Department of the Interior

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VEY GEOL OGICAl. St *p24 llOX 25016 .\l.5 i i 41 1 I)ENVER FEI)ERAl. CENTER l

I)ENVER, Col.ORAI)O 80223 n.m....... March 18, 1987  !

Reactor License:R-113 Docket No. 50-274 Administrator ,oc l U.S. Nuclear Regulatory Commission Region IV .

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. 611 Ryan Plaza Drive Suite 1000 iij l MAR 231981 j Arlingto'n, Texas 76011 4:

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Dear Sir:

i This letter is to notify you that we have found some holes in the aluminum l reactor tank liner that have penetrated the k" aluminum liner. Our reactor 4

is a TRIGA Mark I with the tank below ground level. The tank is surrounded j with four feet of concrete.

We have not been able to determine a leak rate. Annual water loss due to evaporation and possible leakage has not shown a trend. Our loss rate has l been approximately 4000 gallons per year. Over the past six years, the maximum difference between the lowest and highest usage is about 500 gallons, j but there is no trend shown. The variations each year are cyclical.  :

4 l The radiation levels in the reactor water are low. The most recent analyses

{ show a gross < concentration of 4.4 X 10-9 pC1/ml, and a gross ( concentration 1 of 4.8 X 10-8 pCi/ml. H3 concentrations have had a stable history of abouc l 9 X 10-5 pCi/ml. '

We do not believe there is an immediate safety problem. We have suspended  !

l routine operations while we seek to determine the extent of the problem

! and a feasible solution. We will conduct cperations that are needed to satisfy surveillance requirements of our Tech Specs.

i

We will notify you of actions we propose to take to correct the problem

! prior to resuming routine operations.

4 This matter was discussed by telephone with Mr. Ron Baer of Region IV, and

] Mr. Bob Carter of NRR on March 18, 1987. ,

! Sincerely, l ok D 5 4 Qk(( 0 Donald H. Rusling '

i Reactor Supervisor F

l cc: Document Control Desk (2)

Mr. Robert Carter

• l Standardization and Special Projects Directorate

! Division of PWR Licensing - B I .

Office of Nuclear Reactor Regulation

! 614G b ,

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