Morning Report for December 28, 2001
Headquarters Daily Report DECEMBER 28, 2001 *************************************************************************** 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 DEC. 28, 2001 Licensee/Facility: Notification: Southern Nuclear Operating Company MR Number: 2-01-0020 Hatch 1 2 Date: 12/28/01 Baxley,Georgia Dockets: 50-321,50-366 BWR/GE-4,BWR/GE-4 Subject: UNIT 2 REACTOR SCRAM Discussion: Reference Event Number: 38592 On December 25, 2001, Unit 2 automatically scrammed due to high neutron flux. The licensee initially attributed the cause of the scram to a speed increase of the 2A Reactor Recirculation Pump. On December 26, 2001, after reviewing additional data the licensee determined that a rapid steam flow reduction in the 'B' steam line resulted in a Reactor Pressure Vessel pressure increase. The licensee conducted testing of the 'B' steam line and determined that the Outboard Main Steam Isolation Valve disc had separated from the stem. The resulting pressure increase due to the MSIV failure cause in a positive reactivity insertion due to void collapse causing the reactor to scram. The licensee is in the process of evaluating the cause of the stem failure and has planned a 94 hour forced outage to repair the valve. Regional Action: None. Contact: Curt Rapp (404)562-4674 Joel Munday (912)367-9881 _
Page Last Reviewed/Updated Wednesday, March 24, 2021
Page Last Reviewed/Updated Wednesday, March 24, 2021