Lawmakers today issued a new warning that an aggressive antismog plan being pushed by the Environmental Protection Agency could cost the nation $1 trillion, kill another 7.3 million jobs, or 4.3 percent of the workforce in 2020, and halt major construction of highways and factories in employment starved swaths of the nation.

At issue: The EPA’s plan to go far beyond former President Bush’s effort to tighten ozone standards way in advance of the planned review in 2013. It could push much of the nation into non-attainment status under the Clean Air Act, forcing major changes to improve air quality. Most business groups opposed the hurried-up regulations. The National Association of Manufacturers has drawn up a scary map that shows only parts of the central North, the top of Maine and a few other sections of the country that will be in compliance of the new ruling.

Today at the weekly Senate GOP Caucus, Sen. John Barrasso of Wyoming led the opposition. “People in Wyoming are also concerned about jobs, the economy. And this week the Environmental Protection Agency is going to come out with new rules and regulations on ozone, which have been called the most expensive environmental regulations in the history of the United States. The Pennsylvania Chamber of Commerce has said this will cost about 330,000 jobs in Pennsylvania. I think that the — that the focus around the country is on jobs and the economy, and this administration ought to take this 9.2 percent unemployment a lot more seriously than they are taking it right now.”