Thursday, September 11, 2014

Oconee Turned Into Junk

My bad, I assumed this happened yesturday... I guess leaking SRVs are normal??? At least I self check myself...I was looking for if Oconee had repeated issues with SRVs. If I paid attention to the date of the event on 10/24/2013 I wouldn't have put it up.
It is bad when two broken components show up in one plant trip (broken feedwater thing and a leaking relief)...but four misoperating reliefs???

I am certain they reduced pressure by 30 psig by the nature of the trip on their own without going into the procedure...

MANUAL REACTOR TRIP FROM FULL POWER DUE TO FEEDWATER SYSTEM OSCILLATIONS

"At 0553 EDT on 10/24/2013, Oconee Unit 3 was manually tripped due to oscillations in the feedwater system in anticipation of an automatic reactor trip. At 0549 EDT, Unit 3 began experiencing small feedwater oscillations. The feedwater control system was placed in manual in an attempt to stabilize feedwater flows. Feedwater oscillations continued to grow in magnitude and at 0553 EDT, a manual trip was directed to prevent an automatic reactor trip.

"Due to an RPS actuation, this event is being reported as a 4 and 8 hour Non-Emergency per 10 CFR 50.72 (b)(2)(iv)(B) and 10 CFR 50.72 (b)(3)

"Following the reactor trip, four main steam relief valves failed to reseat. Procedure guidance was utilized to reduce main steam system pressure by approximately 30 psig to reseat the main steam relief valves. All main stream relief valves are now reseated. All other post trip conditions were normal and all other systems performed as expected. Unit 3 is currently in Mode 3 and stable.

"Operations have been stabilized on Unit 3. A post-trip investigation is in progress, per site procedures and directives."

The licensee has notified the NRC Resident Inspector.


* * * UPDATE FROM BOB MEIXELL TO DONALD NORWOOD AT 1439 ON 9/10/14 * * *

"Duke Energy reviewed NRC Event Number 49471 against NUREG 1022, Rev 3, section 3.2.6, "System Actuation" and determined this event should have been reported only per 10 CFR 50.72 (b)(2)(iv)(B), RPS Actuation (while critical). Thus, Duke Energy is revising NRC Event Number 49471 to remove the 8-hour report criteria 10 CFR 50.72 (b)(2)(iv)(A). The NRC Resident Inspector was notified of this revised report.

"This update has no effect on safety significance."

Notified R2DO (Shaeffer).

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