That is being driven by the courts.
In 2007 SCOTUS ruled that CO2 was a pollutant, that EPA should determine the risk, and regulate CO2 with the clean air act.
Both Bush and Obama tried to get Congress to deal with it, but Congress failed because of conflicts within the GOP.
That resulted in the 2010 lawsuit against EPA over how and why EPA would regulate CO2
In June 2012, the DC Court of Appeals ruled for the EPA.
In May 2013, the DC Court's decision was appealed to SCOTUS and that is where it sits. Its not known if SCOTUS will take the case or how they might rule.
It is fairly clear what the EPA’s intentions are if you look at the “Carbon Pollution Standards” press release from 9/20/2013. From your post it seems that you believe that the EPA is being dragged kicking and screaming down this path... which forgive me... I find more than a little amusing.
“Todays proposal achieves the first milestone outlined in President Obamas June 25 Memorandum to EPA on Power Sector Carbon Pollution Standards, a major part of the Presidents Climate Action Plan.”
“Under todays proposal, new large natural gas-fired turbines would need to meet a limit of 1,000 pounds of CO2 per megawatt-hour, while new small natural gas-fired turbines would need to meet a limit of 1,100 pounds of CO2 per megawatt-hour. New coal-fired units would need to meet a limit of 1,100 pounds of CO2 per megawatt-hour, and would have the option to meet a somewhat tighter limit if they choose to average emissions over multiple years, giving those units additional operational flexibility.”
http://yosemite.epa.gov/opa/admpress.nsf/0/da9640577ceacd9f85257beb006cb2b6!OpenDocument
Thus the EPA will regulate all existing coal fired power plants out of existance and no new coal fired power plants will be built because it is not possible to meet the proposed regulations with any proven technology currently available. And thus one of President Obama’s first campaign promises to bankrupt anyone who wanted to use coal to generate electricity in this country will be fulfilled.