ML030220037
| ML030220037 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 01/22/2003 |
| From: | Zwolinski J NRC/NRR/DLPM |
| To: | Skolds J Exelon Generation Co |
| Dick G F | |
| References | |
| Download: ML030220037 (5) | |
Text
January 22, 2003 Mr. John L. Skolds, President Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
LICENSED THERMAL POWER - BYRON STATION, UNIT 1
Dear Mr. Skolds:
As a result of the Nuclear Regulatory Commission (NRC) staff review of technical information regarding the operation of Byron Station, Unit 1 (Byron 1), we are concerned that Byron 1 may be operating above its licensed thermal power level.
This concern is based, in part, on the following information:
Following installation of an ultrasonic feedwater flow instrument at Byron 1, differences appeared in the power levels between Byron 1 and Braidwood 1, its sister unit. This suggests differences in accuracy in the ultrasonic flowmeters. Presently, Byron 1 is producing more electrical power at approximately 98 percent power, than Braidwood 1 is producing at 100 percent power.
Several plant parameters reportedly have values that are consistent with a higher thermal power level than that indicated by the plant calorimetrics based upon the feedwater flow measurements. It has been postulated that these discrepancies may be explained as allowable and expected errors in each parameter within the associated uncertainty bands. It seems unlikely that such errors would all exhibit the same consistent bias: errors due to anticipated instrument measurement uncertainties would be expected to be positive or negative at random, and therefore to produce roughly as many low readings as high ones. The consistently positive direction of the reported errors suggests a consistent bias influenced by some common cause, and suggests that the power level may indeed be higher than the calorimetrics would indicate.
There appears to be evidence of higher fuel burn rate at Byron 1 compared to Braidwood 1.
Following approval of a 5 percent power uprate for the units at Byron and Braidwood, Byron 1 has not been able to fully utilize the power increase due to limitations in the high-pressure turbine or steam control valve capacities. Braidwood 1 has not experienced such limitations.
Mr. J. Skolds As a consequence of the above observations, we request that Exelon Generation Company, LLC, expeditiously provide the NRC with assurance that Byron 1 is operating within its licensed thermal power limit or take the necessary and appropriate actions to assure that the unit is within the limit.
Please contact me if there are specific questions.
Sincerely,
/RA by TMarsh for/
John A. Zwolinski, Director Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. STN 50-454 cc w/encl: See next page
Mr. J. Skolds As a consequence of the above observations, we request that Exelon Generation Company, LLC, expeditiously provide the NRC with assurance that Byron 1 is operating within its licensed thermal power limit or take the necessary and appropriate actions to assure that the unit is within the limit.
Please contact me if there are specific questions.
Sincerely,
/RA by TMarsh for/
John A. Zwolinski, Director Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. STN 50-454 cc w/encl: See next page Distribution:
PUBLIC G. Grant, RIII PD3-2 r/f C. Pederson, RIII G. Dick A. Stone, RIII M. Chawla P. Lougheed, RIII C. Rosenberg D. Hills, RIII A. Mendiola OGC F. Akstulewicz ACRS E. Marinos ADAMS Accession Number: ML030220037 OFFICE PM:LPD3-2 LA:LPD3-2 SC:LPD3-2 D:DSSA D:DE NAME GDick CRosenberg AMendiola GHolahan WDean for RBarrett DATE 1/22/03 1/22/03 1/22/03 1/22/03 1/22/03 OFFICE D:DLPM NAME TMarsh for JZwolinski DATE 1/22/03 OFFICIAL RECORD COPY
Byron Station Units 1 and 2 cc:
Regional Administrator, Region III U.S. Nuclear Regulatory Commission 801 Warrenville Road Lisle, IL 60532-4351 Illinois Department of Nuclear Safety Office of Nuclear Facility Safety 1035 Outer Park Drive Springfield, IL 62704 Document Control Desk-Licensing Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Ms. C. Sue Hauser, Project Manager Westinghouse Electric Corporation Energy Systems Business Unit Post Office Box 355 Pittsburgh, PA 15230 Joseph Gallo Gallo & Ross 1025 Connecticut Ave., NW, Suite 1014 Washington, DC 20036 Howard A. Learner Environmental Law and Policy Center of the Midwest 35 East Wacker Drive Suite 1300 Chicago, IL 60601-2110 U.S. Nuclear Regulatory Commission Byron Resident Inspectors Office 4448 North German Church Road Byron, IL 61010-9750 Ms. Lorraine Creek RR 1, Box 182 Manteno, IL 60950 Chairman, Ogle County Board Post Office Box 357 Oregon, IL 61061 Mrs. Phillip B. Johnson 1907 Stratford Lane Rockford, IL 61107 Attorney General 500 S. Second Street Springfield, IL 62701 Byron Station Manager Exelon Generation Company, LLC 4450 N. German Church Road Byron, IL 61010-9794 Site Vice President - Byron Exelon Generation Company, LLC 4450 N. German Church Road Byron, IL 61010-9794 Senior Vice President - Nuclear Services Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President Mid-West Operations Support Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Vice President Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Chairman Will County Board of Supervisors Will County Board Courthouse Joliet, Illinois 60434
Byron Station Units 1 and 2 Illinois Emergency Management Agency Division of Disaster Assistance &
Preparedness 110 East Adams Street Springfield, Illinois 62701-1109 Director Licensing Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Regulatory Assurance Manager - Byron Exelon Generation Company, LLC 4450 N. German Church Road Byron, IL 61010-9794 Senior Counsel, Nuclear Mid-West Regional Operating Group Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President Licensing and Regulatory Affairs Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Manager Licensing - Braidwood and Byron Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555