Headquarters Daily Report DECEMBER 22, 1995 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS û REGION I û REGION II û REGION III û REGION IV û PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION II DEC. 22, 1995 Licensee/Facility: Notification: Tennessee Valley Authority MR Number: 2-95-0108 Sequoyah 2 Date: 12/22/95 Soddy-Daisy,Tennessee Dockets: 50-328 PWR/W-4-LP Subject: MANUAL REACTOR TRIP/TURBINE TRIP DUE TO 161KV YARD VOLTAGE DROP Discussion: On December 21, at 6:27 a.m., Unit 2 was manually tripped by operators from approximately 100 percent power. The reactor trip was initiated when operators noticed condenser vacuum approaching the turbine trip setpoint due to a loss of three condenser circulating water pumps. The condenser circulating water pumps tripped due to a fault condition in the 161 kv switchyard. The fault condition was caused by a failure of power circuit breaker (PCB 974) which caused a voltage drop in the 161 yard for approximately 5 to 7 cycles until the fault was cleared by other breakers opening. The cause of the PCB failure is under investigation. After the trip, operators stabilized Unit 2 in hot standby. AFW was supplying feedwater and decay heat was being removed via S/G PORVs due to the condenser not being available due to loss of circulating water pumps. All safety systems performed as designed. However, the high condenser vacuum trip was being verified as part of the post trip review activities. Unit 1 also lost two of its three circulating water pumps due to the fault. This running pump gave operators on Unit 1 time to restart the two circulating water pumps that tripped prior to Unit 1 condenser vacuum reaching a trip setpoint. Also, a problem associated with the 161 voltage drop involved loss of power to the plant security systems. Backup power for the security systems also failed during this event. Appropriate compensatory measures were promptly initiated. The licensee initiated a post trip review team after the event to review the root cause of trip and the response of the plant to the transient. A plant safety committee meeting was held later on the 21st and unit restart was authorized subject to completion of required corrective actions. Unit 2 went critical at 7:30 this morning. Unit 1 was operating at 100 percent power at the time and was not affected with the exception of the discussion above. Regional Action: The resident inspectors responded to the event, and reviewed the post trip plant conditions, the operators' response to the transient, and attended the PORC meeting for the trip report review. A region based inspector was dispatched to help the residents in their reviews. They will continue to monitor the licensee's post trip review process and recovery actions. REGION II MORNING REPORT PAGE 2 DEC. 22, 1995 MR Number: 2-95-0108 (cont.) Contact: M. SHYMLOCK (404)331-5596 _ REGION III MORNING REPORT PAGE 2 DECEMBER 22, 1995 Licensee/Facility: Notification: Detroit Edison Co. MR Number: 3-95-0192 Fermi 2 Date: 12/20/95 Newport,Michigan SRI PHONECON Dockets: 50-341 BWR/GE-4 Subject: CO2 INITIATION Discussion: WORKERS PREPARING TO TEST THE 2A-2 BATTERY CHARGER WITH A NEW LOAD BANK PLACED BAGS OVER THE FIRE DETECTORS IN THE ROOM. THIS WAS TO PREVENT INADVERTENTLY INITIATING CO2 IF HEATING FROM THE LOAD BANK RAISED DUST. BAGGING THE DETECTORS APPEARED TO CREATE STATIC ELECTRICITY THAT ACTIVATED THE CO2 SYSTEM. THE CO2 ACTIVATED INTO THE ROOM AT 7:54 PM (EST) AND ALL PERSONNEL EVACUATED THE AFFECTED AREA. THE CONTROL ROOM SUPERVISOR EVACUATED THE TURBINE AND AUXILIARY BUILDINGS AS A PRECAUTIONARY ACTION AT 8:00 PM. THE CO2 WAS CONFIRMED TO HAVE INITIATED ONLY IN THE ROOM CONTAINING THE BATTERY CHARGER AND THE EVACUATION WAS TERMINATED AT 11:57 PM. THE RESIDENTS AND THE STATION SENIOR MANAGEMENT WERE NOT CALLED ON THE EVENT. Regional Action: THE RESIDENTS ARE MONITORING THE LICENSEE'S INVESTIGATION INTO THE CAUSES OF THE EVENT. Contact: M. J. JORDAN (708)829-9637 _ REGION III MORNING REPORT PAGE 3 DECEMBER 22, 1995 Licensee/Facility: Notification: Detroit Edison Co. MR Number: 3-95-0193 Fermi 2 Date: 12/21/95 Newport,Michigan SRI PHONECON Dockets: 50-341 BWR/GE-4 Subject: NUCLEAR QUALITY ASSURANCE MANAGEMENT CHANGE Discussion: LICENSEE ANNOUNCED THAT DONALD NORQUIST, DIRECTOR OF NUCLEAR QUALITY ASSURANCE, RESIGNED EFFECTIVE JANUARY 5, 1996. RODNEY JOHNSON, PREVIOUSLY SUPERVISOR OF AUDITS, WILL BE ACTING DIRECTOR - NQA EFFECTIVE DECEMBER 21, 1995. Regional Action: NONE Contact: M. J. JORDAN (708)829-9637 _ REGION III MORNING REPORT PAGE 4 DECEMBER 22, 1995 Licensee/Facility: Notification: Illinois Power Co. MR Number: 3-95-0194 Clinton 1 Date: 12/22/95 Clinton,Illinois SRI VIA TELEPHONE Dockets: 50-461 BWR/GE-6 Subject: MANAGEMENT CHANGES AT CLINTON POWER STATION Discussion: Mr. John Cook, Vice President-Nuclear, has been named to replace Mr. Larry Brodsky as Executive Vice President-Energy Supply for Illinois Power. On December 21, 1995, Mr. Wilfred Connell, Vice President-Fossil, assumed the position vacated by Mr. Cook. Mr. Connell held previous positions at Clinton Power Station during construction as the Manager of Nuclear Assurance, Nuclear Station Engineering, and Planning and Scheduling. The licensee also announced today that Mr. Anthony Mueller, Director-Plant Support Services, will replace Mr. Willie Clark as the Director-Maintenance. The effective date for this change has not been announced. Regional Action: For information only Contact: B. CLAYTON (708)829-9602 _ REGION III MORNING REPORT PAGE 5 DECEMBER 22, 1995 Licensee/Facility: Notification: Iowa Electric Light & Power Co. MR Number: 3-95-0195 Duane Arnold 1 Date: 12/21/95 Palo,Iowa SRI TELEPHONE AND LICENSEE ENS Dockets: 50-331 BWR/GE-4 Subject: HIGH PRESSURE COOLANT INJECTION (HPCI) INOPERABLE Discussion: THE LICENSEE DECLARED HPCI INOPERABLE AND ENTERED A 14 DAY TECHNICAL SPECIFICATION LCO UPON IDENTIFICATION OF EXCESSIVE WATER IN THE TURBINE EXHAUST LINE. THIS SITUATION WAS IDENTIFIED WHILE TROUBLE SHOOTING RECURRING HIGH LEVEL ALARMS ON THE HPCI TURBINE EXHAUST LINE DRAIN POT. THE TROUBLE SHOOTING AND ENGINEERING ANALYSIS RESULTED IN INDICATION THAT THE TURBINE EXHAUST LINE WAS ABOUT 40 PERCENT FULL OF WATER. CHEMICAL ANALYSIS OF THE WATER TO IDENTIFY THE ORIGIN IS INCONCLUSIVE AT THIS TIME. MANUAL DRAINING RESULTED IN REMOVAL OF ABOUT 170 GALLONS OF WATER. AFTER ASSURANCE THAT THE LINE WAS COMPLETELY DRAINED, THE HPCI WAS SUCCESSFULLY TESTED THEN PLACED BACK IN PULL-TO-LOCK STATUS FOR FURTHER EVALUATION. AT ABOUT TEN HOURS FOLLOWING THE TESTING, THE DRAIN POT HIGH LEVEL ALARM HAD NOT RETURNED. UPON INITIAL IDENTIFICATION OF THE PROBLEM, THE REACTOR COOLANT ISOLATION COOLING (RCIC) WAS EXAMINED AND SUCCESSFULLY TESTED WITH NO SIMILAR PROBLEM. ALL OTHER ECCS SYSTEMS ARE AVAILABLE. THE LICENSEE IS CONTINUING THE ASSESS THE EVENT. THE LICENSEE REPORTED THE EVENT IN ACCORDANCE WITH 10 CFR 50.72. Regional Action: THE RESIDENT INSPECTORS HAVE BEEN FOLLOWING THE ISSUE CLOSELY. Contact: T. M. TONGUE (708)829-9613 _ REGION IV MORNING REPORT PAGE 6 DECEMBER 22, 1995 Licensee/Facility: Notification: Nebraska Public Power District MR Number: 4-95-0163 Cooper 1 Date: 12/22/95 Brownville,Nebraska Resident Inspectors Dockets: 50-298 BWR/GE-4 Subject: LIMITORQUE MOTOR PINION KEY FAILURES Discussion: During the current refueling outage, the licensee has discovered three instances where motor pinion gear keys in Limitorque operators have become dislodged, rendering the safety-related valves inoperable. There is an industry history of this failure mechanism and industry corrective action was to stake the keys in the keyway slots to secure them. In these current failures, the keys had been previously staked. Limitorque operators transmit torque from the electric motor to a worm shaft via a motor pinion, which meshes with a worm shaft clutch gear. The motor pinion is secured to the motor shaft with a straight key and a set screw. The key is designed to transmit the rotary forces and the set screw is solely to prevent axial movement of the pinion gear on the shaft. There is a slight clearance fit between the key and the keyways on both the pinion gear and the shaft. Therefore, the staking is required to retain the key. In the current failures, the licensee determined that the staking was inadequately performed. As corrective action, the licensee has verified or will verify that all safety-related valves with Limitorque operators greater than the SMB 00 size have been properly staked. The licensee determined that the SMB-00 and SMB-000 actuators are not susceptible to the phenomenon due to their design and that the lack of similar occurrences in operating history confirms this. Regional Action: The Region has reviewed the licensee's corrective action documentation and has discussed disposition of these concerns with senior licensee management. Contact: Terry Reis (817)860-8185 Rebecca Nease (817)860-8154 _