Headquarters Daily Report SEPTEMBER 18, 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 I SEP. 18, 1995 Licensee/Facility: Notification: Pennsylvania Power & Light Co. MR Number: 1-95-0119 Susquehanna 1 2 Date: 09/18/95 Allentown,Pennsylvania RI TELEPHONE Dockets: 50-387,50-388 BWR/GE-4,BWR/GE-4 Subject: SUSQUEHANNA BREAKER FAILURES (4KV) Discussion: On September 15, 1995, the 2B core spray pump failed to start when the control room start pushbutton was depressed. The licensee determined that the breaker did not attempt to cycle. After the breaker was racked out and then back in, the pump was successfully started from the control room. The licensee believes the problem resulted from a breaker motor cut-off switch misalignment that corrected itself due to vibration during the racking in and out operation. This event was the latest in a series of 4 KV breaker problems that have resulted in safety related pumps failing to start on manual start attempts from the control room. In July, two such manual start attempts of the "C" Emergency Service Water (ESW) pump failed. The licensee replaced the control room handswitch and the pump operated properly during approximately 40-50 subsequent starts. On September 7, the "C" ESW pump exhibited an abnormal start delay. After troubleshooting, during which there were several failures, the licensee concluded that an intermittent malfunction of the latching mechanism was the most probable cause. On September 14, the "B" ESW pump failed to start when its handswitch was depressed. The control logic relays were noted to actuate but, the breaker did not cycle. The licensee determined an intermittent high contact resistance on the spring charging motor cut-off switch was the cause. The affected breakers are 4 KV Westinghouse Porcel-line Type DHP Magnetic Air circuit breakers. The licensee has instituted an interim compensatory measure to rack out/in the breaker if a pump fails to start and is needed. Otherwise, the licensee plans to examine the as-found condition before moving the breaker. The licensee is currently developing a work plan to examine all 4 KV breakers for signs of similar problems. Regional Action: The resident inspectors will continue to monitor the licensee's progress regarding this event. Contact: Clifford Anderson (610)337-5227 _ REGION II MORNING REPORT PAGE 2 SEPTEMBER 18, 1995 Licensee/Facility: Notification: Virginia Power Co. MR Number: 2-95-0083 Surry 1 Date: 09/18/95 Surry,Virginia Dockets: 50-280 PWR/W-3-LP Subject: REACTOR VESSEL LEVEL INDICATION NON-CONSERVATIVE ERROR DURING PREPARATIONS FOR REFUELING Discussion: On September 13 and 14, 1995, reactor coolant was inadvertently drained from the primary system. This was identified by a drop in reactor standpipe level from 18 feet (just below the reactor vessel flange) to 13.3 feet when the reactor head was detensioned at 9:20 am on September 14. Prior to the head being detensioned, the pressurizer relief tank (PRT) had been pressurized to about 10 psig to correct erratic pressurizer level indications. While pressurized, the reactor head vent was isolated to allow refueling cavity seal installation. The vent was not returned to service when the PRT was depressurized. The trapped pressure in the reactor head caused the standpipe's indicated vessel level to increase as the PRT was depressuring. Operators responded to this indicated increase in level by increasing letdown which drained the actual vessel level to approximately 13.3 feet. When the reactor head was detensioned, pressure in the top of the reactor head was released causing the standpipe level to read the correct vessel level. At 10:36 am standpipe level was returned to 18 feet by charging approximately 4500 gallons into the reactor coolant system. Residual Heat Removal System cooling was maintained throughout the event. Regional Action: The Resident inspectors responded to the event. In addition, Region II dispatched two additional inspectors to assist the resident staff. Contact: G. BELISLE (404)331-4196 _