PNO-IV-98-025, on 980615,WNP-2 Initiated Plant Shutdown as Result of Traversing Incore Probe That Could Not Be Moved. Licensee Observed Some Drive Cable Damage & Cable Wrapped Around Some Components Under Reactor Vessel

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PNO-IV-98-025:on 980615,WNP-2 Initiated Plant Shutdown as Result of Traversing Incore Probe That Could Not Be Moved. Licensee Observed Some Drive Cable Damage & Cable Wrapped Around Some Components Under Reactor Vessel
ML20249A598
Person / Time
Site: Columbia Energy Northwest icon.png
Issue date: 06/16/1998
From: Boynton S, Perkins K
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To:
References
PNO-IV-98-025, PNO-IV-98-25, NUDOCS 9806170123
Download: ML20249A598 (1)


June 16,1998

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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-IV-98-025 This preliminary notification constitutes EARLY notice of events of POSSIBLE safe,ty or public interest significance. The information is as initially received without verification or evaluation, and is basically all that is known by Region IV staff in Arlington, Texas on this date.

Facility Licensee Em ;raency Classification Washington Public Power Supply System Notification of Unusual Event Washington Nuclear 2 Alert Richland, Washington Site Area Emergency Dockets: 50-397 General Emergency X Not Applicable

Subject:

TECHNICAL SPECIFICATION REQUIRED SHUTDOWN DUE TO EQUIPMENT PROBLEM On June 15,1998, WNP-2 initiated a plant shutdown as a result of a traversing incore probe that could not be moved. The licensee was unable to close the primary containment isolation valve as a result of the stuck probe and chose to initiate the shutdown rather than isolate the containment penetration using the associated shear penetration valve. Prior to the plant shutdown, the facility had been operating at 38 percent power and was performing power ascension testing following a refueling outage.

As of 8 a.m. (PDT) on June 16, the licensee had observed that the lower coupling between the traversing incore probe ruide tube and the local power range monitoring system dry

nsee indicated that the guide tubes had been removed and tube was disconnected. P -

reinstalled during the refi % stage. The licensee also observed that the traversing incore probe and approximately . ." .eet of drive cable were outside of the guide tube, with the probe located several feet below the lower reactor pedestal work platform. Contact radiation levels of the probe were measured at approximately 10 R/ hour, and contact radiation levels of the drive cable were measured at approximately 2 R/ hour. The licensee observed some drive cable damage, and the cable was wrapped around some components under the reactor vessel.

On June 16, Region IV and NRR held a conference call with the licensee to discuss their recovery plan and repair efforts. The licensee intends to enter containment and cut the drive cable in sections. The drive cable and the probe will be placed in a container and removed from containment. The licensee will replace the probe and drive cable and inspect the other connections of the traversing incore probe system. Currently, the licensee has scheduled a reactor startup on June 17.

The licensee has issued a press release. The state of Washington has been informed.

Region IV received notification of this occuvence from the Headquarters Operations Officer at approximately 3 a.m. (PDT) on June 15,1998. Region IV has informed the OEDO, PAO, and NRR. Region IV sent a reactor inspector to the site to augment the resident inspector staff during the recovery efforts and subsequent reactor startup.

This information has been discussed with the licensee and is current as of 1 p.m. (PST),

June 16,1998.

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Contact:

K. Perkins (925)975-0338 Scott Boynton (509)377-2627 hb 9906170123 980616

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