Part 21 Report - 1996-472
LICENSEE: TENNESSEE VALLEY AUTHORITY
SITE: BROWNS FERRY 2 EN NUMBER:30559
DOCKET: 05000260 EVENT DATE: 05-29-96
RX TYPE: BWR EVENT TIME: 09:15
VENDORS: GE-4 NOTIFY DATE: 05-29-96
EMERGENCY CLASS: N/A REGION: 2 STATE: AL TIME: 13:37
OPS OFFICER: CHAUNCEY GOULD
10 CFR SECTION: AIND 50.72(b)(2)(iii)(D) ACCIDENT MITIGATION
UNIT SCRAM RX INIT INITIAL MODE CURR CURRENT MODE
CODE CRIT PWR PWR
2 N Y 100 POWER OPERATION 100 POWER OPERATION
THE LICENSEE WAS MADE AWARE OF A NONCONSERVATISM IN THE
CALCULATED VALUE OF SAFETY LIMIT MINIMUM CRITICAL POWER RATIO
(SLMCPR) BY GENERAL ELECTRIC.
GE SUBMITTED A PART 21 ON 5/21/96 STATING THAT GENERICALLY SLMCPR
VALUES FOR GE-11 FUEL MAY NOT YIELD THE MOST CONSERVATIVE
RESULTS. THE LICENSEE WAS OFFICIALLY NOTIFIED BY GE THAT CYCLE
SPECIFIC ANALYSIS OF THE OPERATING BROWNS FERRY UNITS HAS BEEN
COMPLETED. FOR UNIT 2, CONTAINING 200 GE-11 FUEL BUNDLES, THE
SLMCPR HAS BEEN DETERMINED TO BE 1.09. FOR UNIT 3, CONTAINING 32
GE-11 FUEL BUNDLES, THE SLMCPR HAS BEEN DETERMINED TO BE 1.07.
THE SLMCPR FOR UNIT 2 IS NONCONSERVATIVE BY 0.02 WITH RESPECT TO
PLANT TECH SPEC 1.1.A.1, WHICH STATES THAT THE MCPR LESS THAN
1.07 SHALL CONSTITUTE A VIOLATION OF THE FUEL INTEGRITY LIMIT.
PRIOR TO STARTUP, AT THE BEGINNING OF UNIT 2 CYCLE 9, THE
LICENSEE HAD IMPLEMENTED, BASED ON PRELIMINARY INFORMATION, A
0.03 - 0.04 PENALTY ON THE OPERATING LIMIT MINIMUM CRITICAL POWER
RATIO (OLMCPR) IN ORDER TO BOUND ANY POTENTIAL NONCONSERVATISM IN
THE GENERIC SLMCPR CALCULATION. THE OPERATING LIMIT PENALTY HAS
ENSURED THAT THE NEW SAFETY LIMIT WOULD NOT HAVE BEEN EXCEEDED
FOR ANY ANALYZED TRANSIENT DURING THE CURRENT OPERATING CYCLE.
THE OPERATING LIMIT PENALTY WILL BE ADJUSTED BASED ON THE
VERIFIED SLMCPR DATA PROVIDED BY GE.
THE RI WAS INFORMED. SEVERAL EVENT REPORTS ON THIS TOPIC WERE
RECEIVED PREVIOUSLY (e.g. #30407, #30509, #30539).
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