WASHINGON, D.C. - Sen. Shelley Moore Capito, R-W.Va., traded proverbial punches with Janet McCabe, acting assistant administrator for the Environmental Protection Agency's Office of Air and Radiation, during a hearing before the Senate Environment and Public Works Committee Tuesday concerning the economic implications of President Barack Obama's air agenda.

The current federal limit on smog-forming pollution linked to asthma and respiratory illness "is not adequate to protect the public health," McCabe said. A lower ozone standard and greenhouse gas reductions from coal-fired power plants "will extend the trajectory of the last 40 years when we've cut air pollution 70 percent - all while our economy has tripled," she said.

Senators on both sides of the issue weighed in, with the bulk of the questioning surrounding the public health benefits of the EPA's new ozone level requirements versus the economic cost for states who must meet the requirement of the new rule by 2020.

The rule, which has origins in an Obama campaign promise, has drawn the ire of Republicans who are already upset about the administration's plans to reduce carbon pollution from coal-fired power plants and to regulate small streams and wetlands.

The administration has not given enough consideration of the "human cost" of stricter regulations on ozone levels, particularly the cost to middle- and lower-income families, Capito said. She cited projections estimating the cost of energy will rise 17 to 22 percent as a result of the regulation. She said this will have an impact on the 430,000 middle- and lower-income people who make an average of $1,900 a month and spend 17 percent of their income on energy.

"What kind of transparency have you brought to areas, like my area in West Virginia, that will be deeply affected?" Capito asked.

McCabe noted the numbers Capito cited did not come from the EPA. She said the Agency did an analysis, as it does for every major rule, which found that by 2030 the average cost of a person's electric bill would go down by 7 percent as a result of increased efficiency.

Capito wondered why the EPA decided to make the nation's top energy exporters the area's hardest hit by the regulation.

"It's all laid out in our discussion. The Clean Air Act tells us to set expectations on industry that are uniform across the country. We set an expected emission rate," McCabe said.

"Which not one plant in my state meets," Capito interjected.

"They're not required to meet it tomorrow; they required to meet it by 2030," McCabe responded.

The new regulation requires states to submit a preliminary plan to reduce emissions by 2016, with a formal plan required by 2017. For states in multi-state compliance groups, plans are due in 2018.

Capito put it bluntly that many governors are planning to ignore the directive to submit the plans. She asked McCabe what would happen if states did not submit plans. She wondered whether they would be the subject of government intervention.

McCabe answered in the affirmative. She said the EPA would step in and develop a plan for the non-compliant states.

U.S. Sen James Inhofe, R-Okla., stated 411 coal-fired power plants would close by 2016 as a result of the rule, with more to follow. This is something he said Capito is acutely aware of given the number of coal fired power plants in the Mountain State.

He wondered if the EPA has done a cumulative study of the effects of this newest regulation.

McCabe responded that, as part of rulemaking, cumulative studies are not something the EPA does. McCabe took issue with the number Inhofe cited regarding plant closures.

"With respect, I don't accept your recitation of choices that are made by power plants; there are more things than environmental rules that go into these decisions," she said.

In voicing support of the EPA rule, Sen. Barbara Boxer, D-Calif, cited an American Lung Association poll that showed more than 70 percent of Americans in favor of stricter ozone standards. She also noted higher ozone levels have proved to be particularly harmful to children and the elderly.

"I've never had a constituent come up to me and say, 'Stop making the air cleaner.' We have an obligation to protect the children and the elderly. If we can't do that what good are we?" Boxer said. "I don't care if one of my colleagues disagrees with me. The important thing is that we listen to the people, not to each other."

Tuesday's hearing came less than a week after Pope Francis stressed the importance of addressing climate change in front of a joint session of Congress. In his remarks, Boxer noted, the Pope called for a "courageous and responsible effort to redirect our steps and to avert the most serious effects of the environmental deterioration caused by human activity."

"This rule is a test as to whether we will heed his call," Boxer said.

U.S. Sen. Tom Carper, D.-Del., said he does not believe stricter emissions standards will cause the negative effects some of his colleagues in the Senate are worried about.

"I think we all want a couple of things. We want cleaner air, but we also want to have a stronger economy. We want to involve states and utilities in appropriate and thoughtful ways," he said. "Most of us want to treat our neighbors the way we want to be treated. The EPA does not lower the ozone standard unless it's found the current standard is not protecting the public. In past years, the EPA has tightened the standard from time to time and the economy has continued to grow."