W3P85-0551, Significant Const Deficiency Rept 93 Re Charging & Letdown Containment Isolation Valve.Potential Exists for Valve to Stick Open Due to Thermal Contraction.Testing Under Temp Conditions Being Performed

Significant Const Deficiency Rept 93 Re Charging & Letdown Containment Isolation Valve.Potential Exists for Valve to Stick Open Due to Thermal Contraction.Testing Under Temp Conditions Being Performed

ML20111A409
Person / Time
Site:	Limerick, Waterford
Issue date:	03/06/1985
From:	Cook K LOUISIANA POWER & LIGHT CO.
To:	Martin R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
93, W3P85-0551, W3P85-551, NUDOCS 8503120489
Download: ML20111A409 (2)

Text

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O LOUISIANA 4.a oe-. .mser . ao.Qx.oo.

P O W E R & L l G H T / NEW ORLEANGL LOUISIANA 70174-8006 . (504) 3SS-W345 MIDDLE SDUTH UTIUTIES SYSTEM March 6,1985 W3P85-0551 3-A1.01.04 A4.05 Mr. Robert D. Martin Regional Administrator, Region IV U.S. Nuclear Regulatory Commission b h $ N h,*. ~

611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76011 ,,

Dear Mr. Martin:

C- M

Subject:

Waterford 3 SES Docket No. 50-382 Significant Construction Deficiency No. 93 Charging and Letdown Containment Isolation Valve Deficiency Additional Supporting Information

References:

1. LP&L letter W3P85-0544 dated February 27, 1985

2. LP&L letter W3P85-0339 dated February 21, 1985 In the reference 1 letter we agreed to provide you further information regarding the findings and planned actions from our investigation of the potentially reportable event (PRE-85-054) of an isolation valve failure.

As you are aware, the event in PRE-85-054 was similar to the problem reported in the significant construction deficiency, SCD-93 (reference 2).

The Letdown Containment Isolation Valve (CVC-103) failed in the open position during plant cooldown. We have concluded that thermal contraction during cooldown has the potential for seizing the plug segments in their open position.

The valve has since been freed, stroked and determined to be operable during cold shutdown. On March 3, 1985 at 0105 hours0.00122 days <br />0.0292 hours <br />1.736111e-4 weeks <br />3.99525e-5 months <br />, when the plant was at normal operating temperature and pressure, the valve was stroked once.

The closure time was 1.5 seconds. To further demonstrate the operability of the valve, the valve will be stroked during different temperature and pressure thresholds as described in the following paragraph.

The valve will be stroked in 100*F decrements during the next two cooldowns starting at or about 100*F below normal operating temperature and pressure.

The surveillance conducted during cooldowns will be in accordance with I d

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85031204B9 850306 PDR S

ADOCK 05000302 PDR 1

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Mr.~ Robert D. Martin W3P85-0551 Page 2 procedure OP-10-001. If the valve fails to close during testing Technical Specification 3/4,6.3 will be envoked and the plant personnel will respond accordingly.

A long term solution will be sought to relieve the plant from this valve cycling exercise, should cycling prove to be the necessary solution to current reliability concerns.

Should you have further questions on the matter at this time please contact C.E. Wuller, Onsite Licensing Coordinator at (504) 464-3499.

Very truly yours, e-

/

.W.

Nuclear Support & Licensing Manager KWC:CEW:sms cc: NRC, Director, Office of 18E G.W. Knighton, NRC-NRR D'.M. Crutchfield, NRC-NRR NRC Resident Inspectors Office INPO Records Center (J.T. Wheelock)

E.L. Blake W.M. Stevenson l

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