Headquarters Daily report APRIL 19, 1995 *************************************************************************** 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 - HEADQUARTERS APRIL 19, 1995 MR Number: H-95-0091 NRR DAILY REPORT ITEM GENERIC COMMUNICATIONS BRANCH/EVENTS ASSESSMENT BRANCH DIVISION OF OPERATING REACTOR SUPPORT OFFICE OF NUCLEAR REACTOR REGULATION Subject: N/A NRC Information Notice 95-22: "Hardened or Contaminated Lubricants Cause Metal-Clad Circuit Breaker Failures," to be issued April 21, 1995. The NRC is issuing this information notice to alert addressees to problems that could result from failing to periodically check the condition of lubricants that may become hardened or contain contaminants used in HK series (4-kV and 6.9-kV) and K-Line (600-V) circuit breakers manufactured by Asea Brown Boveri (ABB, formerly ITE) and DB-50 (480-V) breakers manufactured by Westinghouse. Technical contacts: Rogelio Mendez, RIII (708) 829-9745 Stephen D. Alexander, NRR (301) 415-2995 Sikhindra K. Mitra, NRR (301) 415-2783 NRC Information Notice 95-23: "Control Room Staffing Below Minimum Regulatory Requirements," to be issued April 24, 1995. The NRC is issuing this information notice to alert addressees to several instances in which control room staffing fell below regulatory requirements. Technical contacts: Stuart A. Richards, NRR (301) 415-1031 Neal K. Hunemuller, NRR (301) 415-1152 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I APRIL 19, 1995 Licensee/Facility: Notification: Pennsylvania Power & Light Co. MR Number: 1-95-0057 Susquehanna 2 Date: 04/19/95 Allentown,Pennsylvania RI PC Dockets: 50-388 BWR/GE-4 Subject: Reportable Event Number: N/A Discussion: On April 15, 1995, at 9:07 a.m., the Susquehanna Unit 2 reactor scrammed from 100% power following a turbine trip which was caused by loss of generator load (load reject). The load reject was caused by the automatic opening of the main generator's output breaker by protective circuitry designed to prevent the reverse flow of power from the distribution system to an out of service generator. A mis-wired permissive allowed the circuitry to become enabled when operators were aligning breakers in the switchyard to support offsite maintenance. Once enabled, the circuitry sensed current flow from the generator and tripped open it's output breaker. All plant systems responded as expected during this load reject transient. Twenty five minutes after the scram a voltage dip occurred on Startup Bus #10 while operators were restoring non-safety loads. This voltage dip was not sufficient enough to cause the start of any emergency diesel generator however, several non-vital AC loads automatically transferred to their alternate supplies. One non-vital instrument panel did not properly transfer to its alternate supply due to a failed switch in its uninterruptable power supply. No significant control room indication was lost as a result of this failure and power was restored to the panel within 25 minutes. Regional Action: Followup inspection of the licensee's response to the scram is continuing. Contact: Maitri Banerjee (717)542-2134 John White (610)337-5114 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION I APRIL 19, 1995 Licensee/Facility: Notification: Vermont Yankee Nuclear Power Corp. MR Number: 1-95-0058 Vermont Yankee 1 Date: 04/19/95 Vernon,Vermont RI PC Dockets: 50-271 BWR/GE-4 Subject: LOOSE MAIN STATION BATTERY TERMINAL Reportable Event Number: 28686 Discussion: On April 15, 1995, Vermont Yankee declared the "B" Main Station Battery (MSB) inoperable when an inter-cell battery cable between cells 10 and 11 of the "B" MSB was found only finger tight. The loose cable connection was identified during Technical Specification load profile service testing of the battery which is conducted once per operating cycle during plant outages. The 60 cell battery (2.25 Vdc nominal per cell) was manufactured by C&D Industries. The MSB is located in the cable spreading room and supplies 120 Vdc to safety-related components. The loose connection was identified by a "low cell voltage condition" flagged seconds into the test by the load profile test equipment which monitors each battery cell. A cognizant Electrical Maintenance Supervisor evaluated the condition, directed that the connection be retightened to its torque value, and that the load profile test be continued. The test was completed satisfactorily. Prior to the "B" MSB test, the "A" MSB test was also satisfactorily completed with no abnormal conditions identified. On April 17, a three person licensee investigation team was chartered to evaluate, in part, battery operability, cause(s), and maintenance and test practices. The team was directed to complete their review by Saturday, April 22, 1995. Immediate corrective actions included torque checking all cable connections for both the "A" and "B" MSBs; no additional loose connections were identified. Preliminarily, the team determined that prior to the load profile test, residual heat removal valve (V10-17) which is powered from the "B" MSB, cycled successfully demonstrating "B" MSB functionality. However, this did not confirm post-accident load profile operability which is on the order of 200- 400 amperes for 20-30 minutes. Based on a review of the battery testing and maintenance and security access control information, VY has currently ruled out tampering. The team also determined that the last integrated ECCS test (October 16, 1993) provides some assurance that the "B" MSB was operable following the 1993 refueling outage. VY root cause(s) and operability determinations continues. Regional Action: The resident inspector will continue to monitor the status of VY's investigation. Contact: Paul Harris (802)257-4319 PRIORITY ATTENTION REQUIRED MORNING REPORT - REGION III APRIL 19, 1995 Licensee/Facility: Notification: Commonwealth Edison Co. MR Number: 3-95-0068 Zion 2 Date: 04/19/95 Zion,Illinois SRI VIA PC Dockets: 50-304 PWR/W-4-LP Subject: UNIT 1 STARTUP FOLLOWING REFUELING OUTAGE Reportable Event Number: N/A Discussion: On April 19, 1995, Unit 2 synchronized to the grid following a 104 day refueling outage. The outage was originally scheduled for 76 days. Major contributors extending the outage included repairs to the 2B diesel generator camshaft, repairs to various primary and secondary leaks, electro-hydraulic control system failure, and troubleshooting of safety injection check valve leakage. Regional Action: The residents are following the startup. Contact: L. F. MILLER, JR (708)829-9629