Here is their report on it

They made every nuke plant in the USA recheck their power scheme so that if they lose a phase it would trip the plant from the grid and then wholly depend on the diesel generators.

 Licensee Event Report 2012-001-00

The difference between these guys and I was 1 year before the plant accident I make a complaint to the governor of Vermont about a intermittent short on a fuel pool pump motor. I complained they needed to call it INOP...be shutdown in 30 days of the discovery. Another one is they made believe it was operable for year even as they had it danger tagged out. When I complained, it was 11 months since they should have been shutdown. The electric motor wasn't in stock...they were forced to get a contractor to manufacture this nuclear grade safety motor it for Vermont Yankee. The inisial company no longer carried this kind of electric motor line.

I predicted we were heading for a bad accident with many broken components in the letter to the governor. What caused the LOOP was management taking shortcuts out in the switchyard in order to replace the switchyard batteries. We shorted out both sides of the redundant emergency shityard control power. We had tons of broken and degraded equipment...then severely throttled RHR service water and diesel generator cooling to boost pressure to a rad monitor.