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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