"We looked at the data available. We looked at the technologies," McCarthy told the Senate Environment Committee in January. "We made a determination that (carbon capture and storage technology) was the best system for emission reductions for coal facilities moving forward, because it was technically feasible and it would lead to significant emission reductions."
Whitfield and other critics dispute that, saying carbon capture technology is years away from being commercially viable.
A Senate bill sponsored by Sen. Joe Manchin, D-W.Va., would require the EPA to set standards on based on commercially available technology.
Manchin's approach has drawn support from other Democrats who represent energy-producing states, including Sens. Joe Donnelly of Indiana, Heidi Heitkamp of North Dakota and Mary Landrieu of Louisiana. Landrieu faces a tough re-election fight in a state where both Obama and the EPA are unpopular.
A spokesman for Manchin said Thursday that the senator plans to meet with Senate Majority Leader Harry Reid and other Democrats to discuss a path forward, but did not offer a timetable.
A spokesman for Senate Minority Leader Mitch McConnell, R-Ky., expressed doubts that Manchin's bill will get a vote in the Democratic-controlled Senate.
"If the president doesn't want (the bill), Harry Reid is going to block it, even if it is good for jobs and even it's good for Kentucky," said McConnell spokesman Don Stewart.
Republicans have accused the EPA of dragging its feet on the power plant rule so it won't become final until after the 2014 midterm elections.
EPA Administrator McCarthy announced the proposal in September, but the measure was not printed in the Federal Register until January. The delay means the rule is unlikely to be completed until next year. A public comment period on the rule was supposed to expire next week, but has been extended until May 9.
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