PNO-II-88-018A, suppl to PNO-II-88-018A,issued on 880309. NRC Augmented Insp Team on 880309 Has Completed Onsite Segment of Intended Mission.Licensee Given Concurrence to Restart Unit 2 on 880318 Based on Review of Insp Results

PNO-II-88-018A:suppl to PNO-II-88-018A,issued on 880309. NRC Augmented Insp Team on 880309 Has Completed Onsite Segment of Intended Mission.Licensee Given Concurrence to Restart Unit 2 on 880318 Based on Review of Insp Results

ML20150D469
Person / Time
Site:	Catawba
Issue date:	03/18/1988
From:	Brian Bonser NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
References
PNO-II-88-018A, PNO-II-88-18A, NUDOCS 8803240289
Download: ML20150D469 (2)

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e March 18, 1988 i

.. 1 PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-II-88-18A j

This preliminary notifkation constitutes EARLY notice of events of POSSIBLE safety or I public interest significance. The infomation is as initially received without verifi-cation or evaluation, and is basically all that is known by the Region II staff on this date.

FACILITY: Duke Power Company Licensee Emergency Classification:

Catawba Units 1 and 2 Notification of Unusual Event i Docket No. 50-413 and 50-414 Alert i Rock Hill, South Carolina Site Area Emergency General Emergency ,

X Not Applicable l l

SUBJECT:

AUGMENTED INSPECTION TEAM COMPLETES WORK AT CATAWBA l

This PN supplements PN0-II-88-18, issued March 9, 1988.

l The Augmented Inspection Team (AIT) dispatched by the NRC to Duke Power Company's Catawba nuclear power plant on March 9 has completed the onske segment of its mission. ,

l The AIT was dispatched to the site to review events. associated with inadvertent introduction of ra.v service water into two of Unit 2's four steam generators and clogging )

of two of the auxiliary feedwater flow control valves with asiatic clams, i The licensee declared an Unusual Event and shut down Unit 1 on March 10 after declaring both trains of auxiliary feedwater inoperable because of the events identified earlier in Unit 2. The licensee confimed the Unit's operability and was given NRC concurrence for restart on March 11.

After a review of the test results by the AIT, Region II and NRR, the licensee was given l NRC concurrence to restart Unit 2 at 9:00 a.m. (EST) today. '

The licensee has performed extensive corrective action, including flushing out all stagnant service water lines, radiography of low points in the service water system to check for asiatic clams, and extensive testing of the auxiliary feedwater system.

The licensee determined that a low level in the upper surge tank on Unit 2, coupled with l isolation of the condensate storage tank and auto start configuration, caused low suction pressure, resulting in a swapover of suction to the service water system. It has also been detemined that differences in sensor taps and time delays caused only one train (Train A) to swap to service water.

Normally, auxiliary feedwater is supplied to the steam generators from an upper surge tank, l the condensate storage tank and the condenser hotwell. When the unanticipated switchover occurred, water from the lake was inadvertently introduced, clogging two flow control valves with clams.

The AIT is preparing a report on its findings. The licensee will be meeting with Region II and NRR management to discuss long tem corrective actions and potential enforcement issues.

Local media interest has occurred. Both the licensee and the NRC have responded to media l inquiries.

3 89 880318 -

O\

PNO-II-88-018A DCD y 3y

The States of North and South Carolina have been informed.

Thisinformationiscurrentasof10:00a.m.(EST)onMarch18.

CONTACT: 8. Bonser - 242-4198 DISTRIBUTION H. Street MNPB Phillips _E/_W Willste Regions Chaiman Zech XEUU NRR OIA NMSS Region!-[/ . ,

Comm. Roberts ARM 01 Region II /2D Com. Bernthal EDO Region III -

Com. Carr PA Region IV- /.63 )

Com. Rogers OGC Air Rights Region V - -

SECY SLITP <

OGC-H CA MAIL TO:

FAXT0gy([NicholsonLane DCS Original)

GPA I NPO-- RES ACRS NSAC 00T Trans.only)

PDR LICENSEE '2<'ZO RESIDENT INSPECTOR ~2I/h HQS. OPERATIONS OFFICER 46****************************************************************************************

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