Indiana Michigan Power, an operating unit of American Electric Power (NYSE:AEP), has decided to shut down its 500-megawatt (MW) Tanner Creek 4 generating unit in Lawrenceburg, Indiana, the company announced today. AEP had already decided to retire Tanner Creek's other three generating units in 2011, according to the company's statement.

Approximately 115 employees, AEP said, will be affected by the closure, which should be completed by mid-2015. AEP intends to help find alternative jobs for employees at other AEP facilities, and those who do not secure other employment "will be considered for severance benefits," according to the company.

Commenting on the decision to close Tanner Creek 4, Indiana Michigan Power president and CEO Paul Chodak explained: "The plant's age, combined with new environmental regulations, our successful energy efficiency programs and the fact that we currently don't need additional generation make retirement the best decision for our customers."

Including the closure of Tanner Creek 4, AEP will have retired 7,176 MW of coal-fueled power generation by early 2016, the company said.

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