The shutdown of the Mt. Tom power plant in Holyoke earlier this month signals the end of decades of using coal for generating electricity in Massachusetts.
Mt. Tom, which stopped operating as of June 2, will officially close by October, the last of the state's three coal plants to schedule a permanent shutdown. Salem Harbor Power Station in Salem closed, as previously planned, onJune 1, while Brayton Point in Somerset is scheduled to stop operating in 2017.