ML043640186

Ocgs - Special Report 04-01, Reactor Start-up with the Rod Worth Minimizer Inoperable

ML043640186
Person / Time
Site:	Oyster Creek
Issue date:	12/21/2004
From:	Swenson C AmerGen Energy Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2130-04-20332, OC TS 3.2.B.2.(b) 04-01
Download: ML043640186 (2)

Text

AmerGen Energy Company, LLC www.exeloncorp.com AmerGen An Exelon Company SM Oyster Creek US Route 9 South, RO. Box 388 Forked River, NJ 08731-0388 OC TS 3.2.B.2.(b)

December 21, 2004 2130-04-20332 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 - 0001 Oyster Creek Generating Station Facility Operating License No. DPR-16 NRC Docket No. 50-219

Subject:

OCGS - Special Report 04-01, Reactor Start-up with the Rod Worth Minimizer Inoperable Enclosed is Special Report 04-01 that is submitted in accordance with Oyster Creek Technical Specification 3.2.B.2.(b) due to commencing a reactor startup on November 21, 2004 with the Rod Worth Minimizer (RWM) declared Inoperable. This was the first reactor startup performed during calendar year 2004 without the RWM.

If any further information or assistance is needed, please contact David Fawcett at 609-971 -

4284.

Sincerely, 9I wC / C. Al.6deAJ356 C. N. Swenson Vice President, Oyster Creek Generating Station CNS/DIF

Enclosures:

Special Report 04-01, Reactor Startup with the Rod Worth Minimizer Inoperable cc: S. J. Collins, Administrator, USNRC Region I P. S. Tam, USNRC Senior Project Manager, Oyster Creek R. J. Summers, USNRC Senior Resident Inspector, Oyster Creek File No. 04005

Special Report 04-01 Reactor Startup with the Rod Worth Minimizer Inoperable November 21, 2004 Description of Event The Rod Worth Minimizer (RWM) was declared inoperable on November 18, 2004, prior to 1R20 plant start up because position data for control rods 30-19 and 34-23 were not being registered by the computer when selected by the reactor operator (RO).

Technical Specification 3.2.B.2.b. was entered, which states; "one start-up during each calendar year may be performed without the RWM provided that the second licensed operator verifies that the licensed operator at the reactor console is following the rod program and provided that a reactor engineer from the Core Engineering Group also verifies that the rod program is being followed." The RWM had demonstrated complete functionality during both prior plant start-ups in 2004 including the last start-up on the September 21, 2004 from forced outage 1F07.

Reason for the Failure An initial investigation revealed a loose screw lying on the interface card for control rod 30-19. The screw was removed and operation of the interface card was restored; however, the performance was slow. Subsequently contacts on the rod select relay for the interface card were burnished and normal operation was restored.

Investigations also revealed high resistance across the contacts on the rod select relay for the interface card of control rod 34-23. These contacts were burnished and normal operation was restored for this control rod.

Actions Planned and Scheduled to Repair the RWM The loose screw has been removed and the contacts for the rod select relays associated with the interface cards have been burnished. CAP 02004-3977 and work order C2009175 documents the results of the maintenance and further evaluation of the failure cause. A review of the corrective actions database indicates there is no past history of the RWM failing to recognize rod selections at Oyster Creek. An apparent cause evaluation will be completed by January 21, 2005 to assess extent of condition and to identify additional corrective actions.