ML20028F444

Interim Deficiency Rept Re Mineral Insulated Cable Provided by Kaman Instrumentation for Use w/high-range Drywell Area Radiation Monitors.Initially Reported on 821208.Specs Revised.Also Reported Per Part 21

ML20028F444
Person / Time
Site:	Shoreham File:Long Island Lighting Company icon.png
Issue date:	01/14/1983
From:	Milligan M LONG ISLAND LIGHTING CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, SNRC-818, NUDOCS 8302010359
Download: ML20028F444 (3)

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.- m en w q LONG ISLAND LIGHTING COMPANY

, SHOREHAM NUCLEAR POWER STATION

!=w-a =r- J P.O. BOX 618, tJORTH COUNTRY ROAD

• WADING RIVER, N.Y.11792 Direct Dial Number January 14, 1983 SNRC-818 Mr. Boyce 11. Grier, Director Office of Inspection & Enforcement, Region I U.S. Nuclear Regulatory Commission 631 Park Avcnue King of Prussia, PA 19406 LONG ISLAND LIGHTING COMPANY SHOREHAM NUCLEAR POWER STATION - UNIT 1 DOCKET NO. 50-322

Dear Mr. Grier:

On December 8, 19 0 , in accordance with 10CFR50.55 (e) , we reported verbally to Region I a reportable deficiency involving mineral-insulated (MI) cable, which was provided to us by Kaman In'strumentation for use with our high-range drywell area radiation monitors. This deficiency is the same as that reported to the Commission under 10CFR21 by Kaman by their letter KI-GEN-82-050. Kaman subsequently advised us of the deficiency by their letter KI-SHM-82-061.

This is our 30-day written report on this deficiency. On January 10, 1983, we requested and received an extension of the due date for this report from Mr. J. T. Wiggins of your office.

! Description of Deficiency l

The two high-range area radiation detectors, which are identified at Shoreham as 1Dll*RE-85A and B, are required by NUREG-0737 to be environmentally qualified for design basis accident condi-tions. A sample of MI cable, identical to that specified and provided by Kaman for connection to these detectors within Shoreham's primary containment, was undergoing environmental qualification tenting when a failure occurred. Kaman described the failure in their letter to us as involving moisture penetra-tion through stress-induced cracks in the stainless steel outer jacket of the cable. Kaman determined that the cable failed in such a mar ner as would preclude radiation measurement by these

! instruments during a postulated design basis event.

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SNRC-818 January 14, 1983 Page 2 Corrective Action Based upon their preliminary analysis of the M1 cable failure mode, Kaman has advised us that they are in the process of revis-ing their specification for a better grade of MI cable, which they believe can be adequately qualified. Kaman has not as yet provided us with a firm schedule for their procurement and test-ing of this new MI cable; however, their projections are that it will not be available in time to support initial fuel loading of the Shoretam plant.

As an alternative cable for interim use in this application, we have determined that Brand-Rex triaxial cable has been previously qualified for environmental conditions enveloping Shoreham's cri-teria, and that it will provide acceptable service in the drywell high-range area radiation monitor application. The' insulation resistance of this cable was determined during qualification testing to vayy inversely with temperature, and would drop to a value of 5X10' ohms during exposure to shoreham design basis LOCA temperatures. The effect of this diminighed resistance, as compared with the specified value of 1X10- ohms, is to produce a spurious instrument response which would have a maximum value less than 500 R/hr. Based upon the Shoreham design basis LOCA g temperature profile, the resistance would again increase to 1X10 ohms within six hours of the initiation of the LOCA event, as drywell cemperature decreases, and the instrument response would return to its specified accuracy.

This value of 500 R/hr. comp 9res with the instruments' specified range of 1R/hr. through 1X10 R/hr. and represents a decrease in the true sensitivity of the instrument during the initial six-hour post-LOCA period. This effect has been evaluated by our A/E, S&W Engineering Corp., who determined that these spurious readings would net exceed the action levels calculated for defin-ing initiating conditions for site area or general emergencies.

Therefore, no erroneous emergency action would be taken.

We remain committed to achieving environmental qualification of a cable which will retain all of its specified value3 throughout the duration of any postulated design basis event, and we will replace the interim Brand-Rex cable at the first outage of suf-ficient duration following availability of such a cable. The use of the Brand-Rex cable in the interim period will assure that these detectors are operable throughout any design basis event, and will provide sufficient accuracy as to support safe operation of the plant.

SNRC-818 January 14, 1983 Page 3 We will complete installation and pre-operational / testing of the Brand-Rex cable prior to initial Shoreham fuel loading. Our schedule for installation of a permanent cable remains dependent upon that cf Kaman for procuring and qualifying the' cable. We will, therefore, report to you again when this schedule has become more definLtive.

Very truly yours, A.-M ' D M. 11. Milligan Project Engineer Shoreham Nuclear Power Station GKP/ law cc: J. II!ggins, Site NRC All Parties Mr. Victor Stello, Director NRC Office

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