Capito said she will write a letter to EPA Administrator Lisa Jackson asking whether the agency took into account the economic impact of its regulations.
"Let me be clear, it’s decisions like the one made by AEP today that demonstrate the urgent need to rein in government agencies like the EPA, preventing them from overstepping their bounds and imposing regulations that not only cost us good American jobs, but hurt our economy," said Manchin, an outspoken critic of the EPA.
But EPA defended its regulations Thursday, noting that the agency has worked closely with industry to ensure that its regulations are “reasonable, common-sense and achievable.”
The agency also stressed that the regulations are essential for protecting public health.
“These reasonable steps taken under the Clean Air Act will reduce harmful air pollution, including mercury, arsenic and other toxic pollution, and as a result protect our families, particularly children,” EPA said in a statement.
In a statement outlining its plan to comply with EPA's regulations, AEP said it would need to retire 6,000 megawatts of coal-fired power generation in the coming years.
The company, one of the country’s largest electric utilities, estimated that it will cost between $6 billion and $8 billion in capital investments over the next decade to comply with the regulations in their current form.
The costs of complying with the regulations will result in an increase in electricity prices of 10 to 35 percent and cost 600 jobs, AEP said.
In total, AEP estimated it will have to close five coal-fired power plants by the end of 2014. Six additional plants would see major changes, including retiring some generating units, retrofitting equipment and switching to natural gas.
“We support regulations that achieve long-term environmental benefits while protecting customers, the economy and the reliability of the electric grid, but the cumulative impacts of the EPA’s current regulatory path have been vastly underestimated, particularly in Midwest states dependent on coal to fuel their economies,” AEP CEO Michael Morris said in a statement.
The company said its compliance plan could “change significantly” if EPA’s regulations are altered.