PNO-II-98-025, on 980507,AFW Sys Declared Inoperable.Licensee Isolated Valves 1CM-127 & 2CM-127 in Units 1 & 2, Respectively,To Prevent Recurrence Until Permanent Corrective Actions Can Be Developed

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PNO-II-98-025:on 980507,AFW Sys Declared Inoperable.Licensee Isolated Valves 1CM-127 & 2CM-127 in Units 1 & 2, Respectively,To Prevent Recurrence Until Permanent Corrective Actions Can Be Developed
ML20216A856
Person / Time
Site: Catawba  Duke Energy icon.png
Issue date: 05/11/1998
From: Carroll R
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:
References
PNO-II-98-025, PNO-II-98-25, NUDOCS 9805140280
Download: ML20216A856 (1)


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e May 11, 1998 PRELIMINARY NOTIFICATION OF EVENT OR ifsiUggm_r OCCUnnnCE PNO-II-98-025 This preliminary notification constitutes EARLY notice of events of POSSIBLE cofoty or public interest significance. The information is as initially rcceived without verification or evaluation, and is basically all that is known by Region II staff in Atlanta, Georgia on this date. .

Zapility Licensee Emeraency Classification Duko Power Co. Notification of Unusual Event Cctcwba 1 Alert York, South Carolina Site Area Emergency Dockets: 50-413 General Emergency X Not Applicable Subjcct: AUGMENTED INSPECTION TEAM AT CATAWBA NUCLEAR STATION An Augmented Inspection Team (AIT) has been established to inspect and ccGoss the Catawba Unit 1 Auxiliary Feedwater (AFW) system inoperability on May 7, 1998. (See 10 CFR 50.72 report number 34191.) The AFW system was declared inoperable following the 3:30 p.m. discovery that the Unit's upper surge tanks (normal suction source for the AFW system) were in excocs of the maximum AFW system design temperature of 138 degrees F as listed in the Updated Final Safety Analysis Report. It was determined that an improper controller setpoint (14,400 gpm versus 5,500 gpm) on condsnsate booster pump recirculation valve 1CM-127 had resulted in diverting high temperature condensate to the upper surge tanks during an oorlier unit downpower from 100 percent to approximately 30 percent powar.

The upper surge tanks were returned to less than 138 degrees F by 5:30 p.m. on May 7. Early on May 8, subsequent to an engineering evaluat ion, the AFW system was declared operable. Power escalation followed later in tho dcy once administrative actions were taken to inform operators of the cvent and the control features of valve 1CM-127.

The NRC resident inspector, Headquarters and Regional staffs closely followed the event and due to the significant and unexpected system intoractions, the AIT was established and scheduled to be onsite May 11, 1998. Currently, Unit 1 is at 85 percent power and Unit 2 is at 100 percent power. The licensee has isolated va]ves 1CM-127 and 2CM-127 in Unita 1 and 2, respectively, to prevent recurrence until per.:.anent corrective actions can be developed. i ThIs State of South Carolina and North Carolina have been notified and the NRC will issue a press release announcing the AIT.

Thic information is current as of 10:00 a.m., on May 11, 1998.

Contact:

R. CARROLL (404)562-4511 9905140200 990511

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PDR I&E PNO-II-98-025 PDR

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