(Another lost entry: This was posted yesterday and disappeared into the trash.)
What with the situation in Japan, I’ve been neglecting to report what’s happening at U.S. reactors. Here’s some things from today’s NRC Event Reports:
1. On Monday, techinicians at Crystal River in Florida halted work when acoustic indications suggested “delamination” in a section of the containment structure. Crystal River’s Unit 3 reactor has been shut down since late 2009, when, in the course of cutting a hold in the containment structure to install new steam generators, workers found cracks inside the concrete. Technicians were putting finishing touches on repaired sections of the containment structure when they received the warning about additional cracks. Crystall River claims that the damage to the containment structure was caused by the methods used to cut the hole for the new steam generators, and not the result of embrittlement in the 34 year old facility. Crystal River says that the extent of the addition delamination is not know at this time.
2. Ft. Calhoun in Nebraska yesterday discovered a four-inch conduit that was not properly sealed to prevent flooding. The Event Report says: “Flooding through the penetrations could have impacted the ability of the station’s auxiliary feedwater (AFW) pumps to perform their design accident mitigation functions.”
3. North Anna nuclear plant reported that yesterday, the facility lost power to the ventilation system for the Technical Support Center. From the Event Report: “This condition has the potential to render the TSC unavailable due to the inability of the ventilation and filtration system to maintain a habitable atmosphere.” Power was restored in the afternoon.