After trying hard since January of 2014 to convince Entergy to address safety and reliability issues at their Pilgrim nuclear power plant in Plymouth, Massachusetts, the Nuclear Regulatory Commission officially downgraded the facility's performance rating on September 2 and brought it to the brink of mandatory shutdown. Only two other power reactors out of the 99 operational plants in the U.S. are in the same downgraded category, the two units at Arkansas One, also owned by Entergy.
Pilgrim station began operation in 1972 and received a 20-year license extension in 2012. It is the same GE Mark-1 design as the melted/exploded reactors at Fukushima Daiichi. Massachusetts Senator Ed Markey issued a statement on the NRC action noting that concerns about Pilgrim's operations, security preparedness and safety have been prevalent for years.
Yet another of Entergy's troubled nuclear fleet went down Wednesday (Sept. 16) in Michigan due to equipment failure. The Palisades plant, like Pilgrim and the two Arkansas One reactors, has also suffered a safety downgrade from the NRC. This one due to some 'problems' Entergy Nuclear has with worker radiation dose monitoring and recording.
Entergy Owns 12 reactors, 11 of which are (somewhat) operational since Vermont Yankee was closed in December of 2014. That ties them with Duke Energy since it purchased Progress, now that one unit at Crystal River is shut down for Decommissioning. Exelon has more reactors than any other entity in the U.S. If Entergy's most problematic reactor plants - Pilgrim, Arkansas One (2 units), Palisades, and Indian Point (2 units) - are closed, they will have lost half their fleet.