NRC Special Inspection Ordered After Two Units Trip at Calvert Cliffs

Nuclear Street News Team Tue, Jan 28 2014 10:34 AM A two-unit shutdown caused by a partial power outage at Maryland's Calvert Cliffs nuclear plant last week has provoked a special inspection from federal regulators. On Monday, the Nuclear Regulatory Commission dispatched an additional three inspectors to the plant to review the event and operators' response. The agency also shed additional light on the Jan. 21 outage. In a release, the NRC said snow and ice appear to have affected a ventilation louver filter within a system that distributes off-site power to the plant, causing an electrical fault that disrupted power to systems that included control rod motors and circulating water pumps at unit 2. The power loss also caused the main turbine control circuit to malfunction at unit 1, resulting in its automatic shutdown. On Monday, units 1 and 2 were operating at 97 percent power and 100 percent power, respectively, according to the NRC. They are owned jointly by Exelon and EDF.

South Texas Project Reactor OK After Smoke Fills Computer Room

Nuclear Street News Team Wed, Jan 22 2014 10:31 AM A computer room filled with smoke at the South Texas Project nuclear plant near Houston Saturday. The fire triggered a brief unusual event declaration but did not cause any damage necessitating a shutdown. Unit 1 declared the unusual event – the lowest of the Nuclear Regulatory Commission's emergency classifications – just after 4 a.m. The fire set off an alarm and activated the computer room's Halon fire suppression system, according to a report filed with the NRC and released Tuesday. On-site firefighters found no visible flames. The fire was declared to be under control at 4:12 a.m.; and firefighters confirmed it was completely extinguished by 4:46 a.m. An update to the NRC from the plant later that morning terminated the unusual event just before 10 a.m. At that point, crews were working to restore the affected fire protection systems and repair damaged equipment. The reactor did not shut down, and both units at the plant remained at full power as of Tuesday, according to the NRC.