Part 21 Report - 1997-580
LICENSEE: ILLINOIS POWER CO.
SITE: CLINTON 1 EN NUMBER:32815
DOCKET: 05000461 EVENT DATE: 08-25-97
RX TYPE: BWR EVENT TIME: 00:00
VENDORS: GE-6 NOTIFY DATE: 08-25-97
EMERGENCY CLASS: N/A REGION: 3 STATE: IL TIME: 18:35
OPS OFFICER: LEIGH TROCINE
10 CFR SECTION: CCCC 21.21 UNSPECIFIED PARAGRAPH
UNIT SCRAM RX INIT INITIAL MODE CURR CURRENT MODE
CODE CRIT PWR PWR
1 N N 0 COLD SHUTDOWN 0 COLD SHUTDOWN
10 CFR PART 21 NOTIFICATION - CONTROL CIRCUIT FOR DIVISION 1
EMERGENCY DIESEL GENERATOR (EDG) FEED BREAKER DOES NOT MEET
DESIGN BASIS DUE TO DESIGN ERROR AND COULD PREVENT POWER FOR
DIVISION 1 SAFE SHUTDOWN EQUIPMENT DURING A MAIN CONTROL ROOM
FIRE WITH A LOSS OF OFFSITE POWER.
THIS REPORT INVOLVES THE DESIGN OF THE CONTROL CIRCUIT FOR
DIVISION 1 EDG 4-KV 1A1 FEED CIRCUIT BREAKER 252-DG1KA. THE
CONTROL CIRCUIT DESIGN WAS SUPPLIED BY SARGENT & LUNDY. IN
ACCORDANCE WITH THE SAFE SHUTDOWN ANALYSIS AND 10 CFR PART 50,
APPENDIX R, SECTION III.L, THE CONTROL CIRCUIT FOR THE BREAKER IS
REQUIRED TO BE DESIGNED TO ALLOW ISOLATION OF THE MAIN CONTROL
ROOM WIRING/CONTROLS AND OPERATION OF THE BREAKER FROM THE
REMOTE
SHUTDOWN PANEL DURING A FIRE IN THE MAIN CONTROL ROOM.
THE NATURE OF THE DEFICIENCY IS THE ABSENCE OF ISOLATION CONTACTS
IN THE DESIGN OF THE OFFSITE SOURCE PERMISSIVE HAND SWITCH
CIRCUIT. SINCE THE CIRCUIT INCLUDES A CABLE IN THE MAIN CONTROL
ROOM, IT SHOULD BE ISOLATED TO ASSURE OPERABILITY OF THE EDG FEED
BREAKER WHILE PLACING THE PLANT IN SAFE SHUTDOWN FROM THE REMOTE
SHUTDOWN PANEL. DURING A POSTULATED FIRE IN THE MAIN CONTROL
ROOM CONCURRENT WITH A LOSS OF OFFSITE POWER, FIRE COULD DAMAGE
THE MAIN CONTROL ROOM CABLES. THIS IN TURN COULD CAUSE MULTIPLE
GROUND FAULTS, THE LOSS OF CONTROL POWER FOR THE DIVISION 1 EDG
FEED BREAKER, AND A LOSS OF POWER TO DIVISION 1 EQUIPMENT. THE
SAFE SHUTDOWN ANALYSIS RELIES ON DIVISION 1 EQUIPMENT OPERATED
FROM THE REMOTE SHUTDOWN PANEL IN ORDER TO BRING THE PLANT TO A
SAFE SHUTDOWN CONDITION IN THE EVENT OF A FIRE IN THE MAIN
CONTROL ROOM.
THIS ISSUE POTENTIALLY AFFECTS ALL CIRCUITS ROUTED THROUGH THE
REMOTE SHUTDOWN PANEL. THE FOLLOWING TWO CIRCUITS WERE
IDENTIFIED TO BE DEFICIENT IN DESIGN: THE CONTROL CIRCUIT FOR
BREAKER 252-DG1KA AND THE CONTROL CIRCUIT FOR THE DIVISION 1
ESSENTIAL SWITCHGEAR HEAT REMOVAL SYSTEM FAN DAMPER.
THE LICENSEE IS NOT AWARE OF OTHER FACILITIES THAT WOULD BE
AFFECTED BY THIS DEFICIENCY.
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