Morning Report for April 15, 1999
Headquarters Daily Report APRIL 15, 1999 *************************************************************************** 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 II APRIL 15, 1999 Licensee/Facility: Notification: Tennessee Valley Authority MR Number: 2-99-0009 Watts Bar 1 Date: 04/15/99 Spring City,Tennessee Dockets: 50-390 PWR/W-4-LP Subject: MANUAL REACTOR TRIP DURING REACTIVITY CONTROL SYSTEM TESTING (REPORTABLE EVENT NO. 35573) Discussion: On April 11, 1999 at 00:42 a.m., Unit 1 experienced a continued outward control rod motion for shutdown bank A upon release of the rod control switch. This problem occurred during pre-startup control rod testing following the refueling outage. The operator appropriately opened the reactor trip breakers and all shutdown bank a control rods fully inserted as expected. All other control rods were fully inserted at the time that shutdown bank A was being tested. Reactor coolant system boron concentration was at 2184 ppm with the unit in Mode 3 at normal operating temperature and pressure. Subsequent troubleshooting identified a defective logic control card in the master cycler. The logic control card was replaced and pre-startup control rod testing was completed satisfactory with no additional problems. The resident inspectors have been following licensee troubleshooting and corrective actions activities. The licensee is planning to return the defective logic control card to the vendor (Westinghouse) for a detailed failure analysis. Currently the unit is operating at 14 percent power, conducting post-startup tests prior to resuming full power operation. Contact: PETER TAYLOR (404)562-4562 _
Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021