ML20064A549

Responds to NRC Re Violations Noted in Insp Repts 50-373/90-12 & 50-374/90-13.Corrective Actions:Program Implemented Identifying & Correcting Repetitive Local Leak Rate Failures Through Testing & LER Investigation

ML20064A549
Person / Time
Site:	LaSalle
Issue date:	07/27/1990
From:	Morgan W COMMONWEALTH EDISON CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
NUDOCS 9009140087
Download: ML20064A549 (3)

Text

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Commonw:alth Edison T

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Downers Grove, Iliinois 60515 i

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July 27,.1990

,4 Mr' A. Bert Davisc 1

Regional' Administrator-U.S. Nuclear Regula. tory Commission' 1

Region.III

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A-c799 Roose/eltLRoad-Glen Ellyn,'IL :601373

Subject:

LaSalle County Station Units 1 and 2:

Response to Inspection ReportL50-373/90012

(

and-50-374/90013 NRC Docket Ne'

. )-)73 'and 50-374; 4

Reference:

(a) H.J.~ Miller letter to C. Reed.

dated July 27',11990.

Dear Mr.= Davis:

.This letter is in response-to reference (a).where Commonwealth l

Edison's LaSalle County Station was requested to provide a: response: addressing

.the program for correct repetitive local' leak rate failures. ~

The following attachment provides.thefcommonwealth Cdison response:to this request.

~i If you have any further questions regarding._this matterT please i

contact this office.

Very.truly yours, b

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.l H. E.

argan

. Nuclear Licensing Administrator J

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cc:

NRC Resident. Inspector - LSCS l-

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1mw/10132 9009iio~o97 9997,,

{DR ADOCK 05000373 PDC AUG 14 mo

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.f ATTACHMENT l

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50-373/90012 (30-374/90013)6 j

ImRalle Response'to Inspection Rgoort

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-Renardinn Repetitive Local Leak Rate Test Failurgg; q

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In response lto Inspection' Report' 50-373/90012',LLaSalle Statidn.was?

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c requested to. address the program 1forLeerrecting_ repetitive <1ocal-leak: rate; h

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failures'. LaSalle Station = believes they;have impien ted an effective programi i

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for identifying'and' correcting repetitivellocall leak rate failures.- This is' lj L

. achieved.through testing, Licensee Event' R Tort l(LER) investigation, 'and:

'O engineering' analysis ' to dete'rmine short' and'long term. corrective actions. : The) j success of.this' method.is demonstratedhin)the referenced. inspection report l l

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h regarding'Feedwater^ Check Valves. ELaSa11e' Station has initiated additional-i j" '

programs for' addressing the; repetitive local leak rateLfa11urescfor certain affected primary containment penetrations. These-affected. primary containment

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' penetrations. along with~their specific corrective ' actions-- are - 1f sted' as :

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follows:

1 Reactor' Water'Cleanuo'(RWCU):

-An' Engineering investigation will be conducted regarding possible. replacement?

or modification programs forithe.RWCU Suction 1Line. Isolation Valves,-

1(2)G33-F001 and 1(2)G33-F004.

.The final-replacement and/or modification 1

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program chosen'willLensure minimum leakage through these valves._ Due to the time' constraints associated with replacement of=these valves,LLaSalle-Station =

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~I has decided not to' install a different type.of_ valve for this application L

during the next refueling outage, as origina11y' scheduled.'

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Main Steam Isolation Valve Outside Drains-1 An Engineering investigation'similar to'the investigation for the RWCUfEu'ction j

Line Isolation Valves will be conducted for the Main Steam' Isolation Valre-t Outside Drain Valves,-1(2)B21-F067A/B/0/D.

'l Drvwell Floor Drains and Eauloment Draina ' (DWFD.~ 'DWED)

LaSalle Station has identified that the:cause of the local leak rate testi i

failures'for the Drywell Ficor/ Equipment Drain Sump as being.fo'eignsobjects q

r becoming caught in the valve seats.' These objects;have entereditheLDWFD/DWED systems through their Drywell Sumps.

LaSalle Station;is:investigatingithe use of: filtering screens to be-placed in the DWFD/DWED' Sumps duringcextended-(refuel) outages.

In~ addition, LaSalle Station is considering per'. odic inspection and c?eaning of the subject. sumps.

It is expected that placing:the

,3 temporary screens in the subject sumps as well as periodic inspections of the-L sumps will prevent foreign objects f rom being caught in the DWFDS/DWEDS -

1 Isolation Valves.

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LlIbaide MSIV Draina. C M ustible Gan' Control'.

4 Chilled Cleanina Pronram' 39 hfter reviewing the local. leak.rateitest history.ofithe valves-described in Sections 5.c.e,f, and g ofLthe-Inspection.' Report,"LaSa11e' Station believes that the subject f ailures are not' repetitive bht sporadic in nature.

LaSalle Station:will review the local leak rate-test results'for thelsubject

. penetrations'at the end.of--theLUnit 2. fourth refueling outagelin order to s

l identify any further failure trends'.that;could be' regarded as. repetitive; Based upon=the future local ~ leak rate test results for these penetrations,

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additional programs ~for minimizing valve leakages may be incorporated.:

To ensure completion of these' actions,; all' of. the' above mentioned.

Engineering investigations and followup corrective'-actions will be' tracked by.

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l the:LaSalle Station. Commitment Tracking System.:

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