Headquarters Daily report AUGUST 29, 1994 *************************************************************************** REPORT NEGATIVE NO INPUT ATTACHED INPUT RECEIVED RECEIVED HEADQUARTERS X REGION I X REGION II X REGION III X REGION IV X *************************************************************************** PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION III AUGUST 29, 1994 Licensee/Facility: Notification: Commonwealth Edison Co. MR Number: 3-94-0150 Quad Cities 1 2 Date: 08/29/94 Cordova,Illinois E-MAIL Dockets: 50-254,50-265 BWR/GE-3,BWR/GE-3 Subject: STARTUP OF BOTH UNITS Reportable Event Number: N/A Discussion: On August 27, 1994 at 1:41 p.m, CDT, Unit 2 was synchronized to the grid. Unit 2 tripped on August 23 due to spurious closure of MSIVs. The licensee determined that the cause of the MSIV closure was a mechanical shock to main steam flow detector sensing lines by workers. On August 28, 1994 at 10:40 a.m., CDT, Unit 1 was synchronized to the grid to end its refuel outage. The refuel outage started on March 13, 1994. Major outage activities included: motor operated valve testing, torus recoat, reactor vessel internals inspection, and overhaul of the high pressure coolant injection system. Regional Action: The resident inspectors office will continue to monitor Unit 1 power escalation activities. Contact: P.L. HILAND (708)829-9603 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION III AUGUST 29, 1994 Licensee/Facility: Notification: Commonwealth Edison Co. MR Number: 3-94-0151 La Salle 2 Date: 08/29/94 Marseilles,Illinois VIA ENS Dockets: 50-374 BWR/GE-5 Subject: RESTART OF UNIT 2 FOLLOWING TH E AUGUST 25, 1994, AUTOMATIC REACTOR SCRAM Reportable Event Number: 27705 Discussion: At 3:27 a.m. on August 25, 1994, LaSalle Unit 2 was operating at 99% power when the control valve (CV) circuitry malfunctioned causing the control valves to partially close. As the control valves went closed, reactor pressure began increasing. The bypass valves properly responded to the pressure increase and sequentially opened. When all five bypass valves reached full open, reactor pressure continued to increase which caused reactor power to increase to the point of reaching the average power range monitor (APRM) Hi Flux scram setpoint. Earlier during the same shift, there were two similar but much shorter duration control valve oscillations which resulted in pressure rises that were controlled by a single bypass valve. These two events had no other effects on the plant. Operations had contacted the Instrument Maintenance Department to start troubleshooting. Plant response during the transient and following the scram was as expected with minor exceptions. The 2C VP (primary containment cooling) Chiller tripped during the fast transfer of bus 242X(238). It was then manually isolated since the 2A VP Chiller remained in service and the additional cooling provided by 2C was not required for containment cooling with the unit shut down. In addition, the 2D intermediate range monitor (IRM) failed to fully insert following the scram and the 2D condensate pump experienced increased seal leakage. During troubleshooting of the electro-hydraulic control (EHC) system, speed error changes were noted in conjunction with pressure amplifier operation. Therefore, the licensee replaced a primary pressure amplifier and its associated operational amplifier circuits. Testing also identified that control valve number 1 Servo-amplifier- demodulator-indicator should be replaced. It was also observed that several circuit boards were not fully seated in their connectors. The licensee believes that the CV closures were a result of spurious discontinuity in the load or speed circuits. The licensee began starting up the unit on August 27, 1994, after troubleshooting and repairing the EHC system. On August 28, 1994, after the licensee closed the main turbine stop valves before seat drains, condenser in-leakage and off-gas flow increased. Investigation revealed a hole in a restricting orifice in the main turbine stop valve drain line to the condenser which was causing a loss of condenser vacuum. The main turbine will not be put on-line until after this is repaired. Regional Action: The resident inspectors responded to the event and are continuing to follow the licensee's restart activities. Contact: BRENT CLAYTON (708)829-9602