NPL-99-0319, Provides Main Control Board Wiring Separation Project Status Update Rept for Pbnps,Units 1 & 2

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Provides Main Control Board Wiring Separation Project Status Update Rept for Pbnps,Units 1 & 2
ML20195D482
Person / Time
Site: Point Beach  NextEra Energy icon.png
Issue date: 05/28/1999
From: Findlay M
WISCONSIN ELECTRIC POWER CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NPL-99-0319, NPL-99-319, NUDOCS 9906090178
Download: ML20195D482 (2)


Text

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Wisconsin Electnc i

. POWER COMPANY i I

Point Beach Nuclear Plant (920) 755-2321 I' 6610 Nuclear Rd., Two Rivers. WI 54241 l

NPL 99-0319 ~ j May 28,1999 Document Control Desk U.S. NUCLEAR REGULATORY COMMISSION Mail Station PI-137 Washington,DC 20555 Ladies / Gentlemen:

DOCKETS 50-266 AND 50-301 MAIN CONTROL BOARD WIRING SEPARATION PROJECT STATUS UPDATE POINT BEACH NUCLEAR PLANT UNITS 1 AND 2 As reported in LERs 301/91-001-01 and 266/96-007-00, the original design and wiring practices used inside of the Point Beach Nuclear Plant (PBNP) main control boards did not include rigorous application of physical separation criteria for wires associated with redundant trains of safety-related equipment and independent instrument channels. This physical separation is one of the important design features that ensures a single fault within one train or channel circuit does not cause damage to the other train or channel circuit and thereby disable a safety function.

Our letter to the Commission dated April 16,1997, transmitted an operability determination for this situation to support continued operation. It further described corrective actions taken to date and provided a restoration plan and schedule for completing wire separation and rerouting during the upcoming refueling outages of both units. The letter confirmed information discussed during a telephone conference held on March 10,1997, between representatives of Wisconsin Electric (WE) and the NRC staff.

' In our letter to the Commission dated January 27,1998, we reported that the project scope had been significantly expanded. We provided the details and schedules for accomplishing the additional work.

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We also indicated that we had prioritized the order of work based upon the probabilistic safety  !

assessment risk significance of the system for which wires were being routed.

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  • NPL 99-0319 May 28,1999 Page 2 I

i The following tabulation summarizes project status to date and our schedule for completing main control  ;

board wiring separation commitments: i e Work packages to correct inadequate physical separation for Unit 2 control board wiring have been completed. This includes both original and expanded scope work activities.

3 Ei+.iations ofinadequate physical separation in common main control boards C01 and CO2 have been corrected, with the exception of emergency diesel generator G01 rewiring in C01. Work on G01 rewiring will be performed during the next scheduled emergency diesel generator overhaul outage.

This outage is presently scheduled for late 2000 or early 2001.

. Original scope rewiring in the Unit I main control boards was completed during UIR24. As reported to you in our January 27,1998 letter, remaining expanded scope wire separation work is scheduled to be completed by the end of the upcoming UlR25 outage.

Sincerely,

/

Mark P. Findlay, P .D.

Manager, h

Regulatory Se ices & Li e sing  !

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.. l cc: NRC Regional Administrator )

NRC Resident Inspector

- NRC Project Manager PSCW _i INPO Support Services I i

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