Headquarters Daily Report SEPTEMBER 13, 1996 *************************************************************************** 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 SEP. 13, 1996 Licensee/Facility: Notification: Virginia Power Co. MR Number: 2-96-0080 Surry 2 Date: 09/13/96 Surry,Virginia Dockets: 50-281 PWR/W-3-LP Subject: SURRY UNIT 2 REACTOR COOLANT SYSTEM (RCS) LEAKAGE Discussion: On September 11, 1996, Surry Unit 2 personnel noted increased RCS leakage that was identified to be coming from a crack in a coupling on the normal letdown line. The line was isolated and excess letdown was put into service. The crack was repaired on September 12-13, 1996. Since 1987 there have been 5 various weld leaks in the letdown line joints in this unit. These occurred in 1987, 12/95, 3/96, 8/96, and the current one. The licensee has instituted a high priority evaluation to determine the root cause of these problems. Regional Action: The resident and region-based inspectors will followup the licensee's engineering evaluation. Contact: G. Belisle (404)331-4196 _ REGION IV MORNING REPORT PAGE 2 SEPTEMBER 13, 1996 Licensee/Facility: Notification: Entergy Operations, Inc. MR Number: 4-96-0098 Arkansas Nuclear 1 Date: 09/12/96 Russelville,Arkansas RESIDENT INSPECTOR Dockets: 50-313 PWR/B&W-L-LP Subject: REACTOR TRIP EN: 30995 Discussion: On September 12, 1996, at 12:10 p.m., Unit 1 tripped from 100 percent power. At the time of the trip, the licensee was preparing to perform maintenance on a startup transformer. While racking down the startup transformer electrical supply breaker (Breaker H-13) to 6.9 Kv Bus H-1, the breaker springs discharged as expected. The vibration from the discharging of the springs apparently actuated the undervoltage relay on the adjacent breaker cabinet, H-14, which is the auxiliary transformer electrical supply to Bus H-1. Breaker H-14 opened, de-energizing electrical power to Bus H-1. Since Reactor Coolant Pumps (RCP) A and C are powered from Bus H-1, these pumps tripped. The reactor tripped as expected following the loss of two reactor coolant pumps while at 100 percent power. The primary systems responded as expected for this event, with one RCP running in each loop. Two equipment problems were experienced. The main feedwater block valve to Once Through Steam Generator (OTSG) B did not close automatically as designed. Main Feedwater Pump B usually supplies water to OTSG B following a trip; however, since the valve did not close, the integrated control system did not feed OTSG B, and level reached the initiation setpoint for emergency feedwater. Emergency feedwater initiated as designed and filled OTSG B. The cause of the failure of the Main Feedwater Block Valve B to go closed has not been determined. Also, RCP C zero speed indication failed causing the need for the operators to manually start the high pressure oil pump to RCP C. The cause for the failure of the zero speed indication of the RCP C has not been determined. The licensee found that a fuse to the undervoltage relay for breaker cabinet H-14 is located inside the H-13 breaker cabinet. The fuse had intermittent continuity which was lost during the discharging of Breaker H-13 springs. The licensee plans to remain shut down and start Refueling Outage 13 early. The outage had been scheduled to start at 12:01 a.m. on September 17, 1996. Regional Action: The resident inspector responded to the control room shortly after the trip and observed plant recovery actions. The resident inspector will review licensee corrective actions to address the causes of the trip and equipment problems. Contact: E. Collins (817)860-8291 _