PNO-I-97-040, on 970627,Unit 1 RPS Trip Functions Did Not Meet Design Requirements & Were Inoperable.Licensee Intends to Install Design Change to Resolve IEEE-279 Postulated Failure Concerns.Operators Began TS Required Shutdown

PNO-I-97-040:on 970627,Unit 1 RPS Trip Functions Did Not Meet Design Requirements & Were Inoperable.Licensee Intends to Install Design Change to Resolve IEEE-279 Postulated Failure Concerns.Operators Began TS Required Shutdown

ML20141E826
Person / Time
Site:	Beaver Valley
Issue date:	06/30/1997
From:	Eselgroth P, David Kern NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To:
References
PNO-I-97-040, PNO-I-97-40, NUDOCS 9707010171
Download: ML20141E826 (2)

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DCS No.: 0503334970627

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l Date: June 30,1997

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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PN1-97-040 l This preliminary notification constitutes EARLY notice of events of POSSIBLE safety or l l public interest significance. The information is as initially received without )

l verification or evaluation, and is basically all that is known by the Region I staff on i I

this date.

Facility: Licensee Emergency Classification:

Duquesne Light Company Notification of Unusual Event Beaver Valley 1 and 2 Alert Shippingport, Pennsylvania Site Area Emergency General Emergency X Not Applicable Docket No.: 050-00334 License No.: DPR-66 Event No.: 32556 Event Location Code:

SUBJECT:

BEAVER VALLEY UNIT 1 SHUTDOWN GREATER THAN 72 HOURS On June 27,1997, while evaluating maintenance rule scope applicability, Duquesne Light Company (DLC) engineers determined that two Unit 1 reactor protection system (RPS) trip functions did not meet design requirements and were inoperable. The low-low steam generator (SG) RPS trip function was inoperable because the installed system did not satisfy lEEE-279-1971 postulated failure scenarios. The steam flow /feedwater flow mismatch coincident with low SG level RPS trip was inoperable because six feedwater transmitters (two per steam generator) did not meet UFSAR commitments to IEEE-279 (e.g. seismic installation). A third, but unrelated, issue subsequently arose when engineers determined that the feedwater regulating valve (FRV) bypass valves were not constructed to QA category I requirements and therefore would not assure feedwater isolation upon a feedwater rupture inside containment accident.

The licensee entered TS 3.0.3 at 7:15 pm on June 27,1997, due to the plant being outside its design basis. Operators began a TS required shutdown at 8:13 pm and achieved hot standby at 1:28 am on June 28,1997.

The licensee intends to install a design change (SG level transmitter median selector switch) to resolve the IEEE-279 postulated failure concerns. A TS amendment request to eliminate the flow mismatch coincident with low SG level trip is being prepared to resolve the second issue. The FRV bypass valves will be replaced with QA category i valves to address the third issue.

The licensee anticipates shutdown duration to be greater than one week. Major work includes seismic evaluations of reactor coolant system excess letdown piping supports and repair of turbine electro-hydraulic control fluid leaks in addition to the work i discussed above. DLC is considering moving a planned refueling outage up by two months i to coincide with this forced outage, l

l The contents of this PN have been communicated to the Pennsylvania, Ohio and West Virginia state governments.

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9707010171 970630 \/'

j PDR 18 E PHO-I-97-040 PDR , g{

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, Ths resid:nt inspsetors obstrvsd enginsering svaluation of tha design issuns end

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• moniforsd the reactor shutdown. Tha insp;ctors will continun to evaluate licensse assessment of the design issues and associated corrective actions prior to restart.

Contact:

ESELGROTH, PETER KERN, DAVID  ;

(610)337-5234 (412)643-2000 DISTRIBUTION:

OWFN TWFN LST Mail: DCD Chairman Jackson AEOD PDR DOT:Trans only'*

Comm. Rogers IRM Comm. Dicus ACRS Comm. Diaz Comm. McGaffigan Jr.

OCAA NRC Ops Ctr OIP OCA NMSS OGC OlG INPO '

• OPA RES NSAC**

EDO OE OSP NRR* * (Phone Verif: Violet Bowden 415-1168 or 415-1166)

SECY

. Regional Offices RI Resident Office Licensee:

(Reactor Licensees)

• Generallist for sending PNs by FAX Region I Form 83 (Rev. August 1996) l

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