With newly mandated power to regulate the environment, the U.S. Environmental Protection Agency is facing congressional legislation to the opposite effect—including a vote from Illinois Senator Mark Kirk that would weaken the EPA’s ability to clean certain air pollutants.

Kirk’s vote on March 16, his first on a major environmental issue since being sworn in to his Senate seat on Nov. 29, 2010, was in support of an amendment to Senate bill 493, which would have blocked the U.S. EPA from regulating carbon dioxide—the main contributor among greenhouse gases in the atmosphere. Attempts to weaken the Clean Air Act, otherwise known as the basic framework for environmental regulation in the U.S., have abounded in recent months.

“The reason Illinois is so important is because we have so many elected officials who can make an impact on what happens to the Clean Air Act,” said Nancy Wagner, policy consultant for the Union of Concerned Scientists.

Though the amendment failed due to a lack of the necessary 60 votes, Kirk’s position is in line with a segment of Illinois politicians that have maintained opposition to EPA regulatory power. Illinois Representatives John Shimkus and Robert Dold, who holds Kirk’s former congressional seat, also voted for the amendment.

Similarly, the Energy Tax Prevention Act, H.R. 910, dubbed the “Dirty Air Act” by opponents, passed the U.S. House of Representatives on April 6 and seeks to block the EPA from cutting carbon emissions and overturn the agency’s “endangerment finding”—which states that global warming is a threat to public health. The bill, sponsored by Rep. Fred Upton, D-Mich., passed the House by a vote of 255-172, to the dismay of policy enhancement advocates.

“You’re going to see a number of bills and actions to weaken the Clean Air Act and reduce the ability of the EPA to do its job,” said Illinois Representative Mike Quigley, longtime supporter of environmental policy reform. “They do this under the false mantle of job creation or job protection, but that’s simply not the case.”

According to Quigley, congressional environmental policy needs to take the best and most recent science into account when legislating a subject so nuanced by local conditions. In Illinois and the nation, transportation systems, local weather conditions, industry and health care are some of the necessary considerations for creating comprehensive environmental standards.

“We recognize Chicago is still the morbidity and mortality capitol in the country for asthma,” Quigley said. “We still have two antiquated coal-burning power plants right here. We have a slew of issues to address.”

After a Supreme Court ruling placed regulation of carbon dioxide, now officially categorized as a harmful greenhouse gas emission, under its jurisdiction, the EPA began working to create new rules and regulations. The first set, which will regulate stationary source pollutants, such as Chicago’s Fisk and Crawford coal plants, 1111 W. Cermak Road, and 3501 S. Pulaski Road, is set to be released in July.

According to Wagner, stationary source pollutants are the largest source of greenhouse gases but can be difficult to regulate because they don’t necessarily accumulate directly where they are emitted. Carbon pollution frequently crosses state lines, causing cumulative negative health effects in U.S. residents.

While the EPA has had the ability to regulate carbon emissions since Jan. 2, the agency is cautious about making big changes too quickly.

New rules regulating nonstationary pollutants, such as cars and trucks, have remained relatively unchallenged. However, environmental policy advocates expect threats to the Clean Air Act and EPA will continue in coming months.

While the nation struggles to adopt an appropriate environmental strategy, certain localities, including Chicago, are developing policies that reach beyond Clean Air Act standards.

Illinois meets the vast majority of imposed regulations, according to Dennis McMurray, spokesman for the Illinois EPA, but discussion about whether those regulations are stringent enough is ongoing.

The debate continues in Illinois and across the country while Congress, including Kirk, who could not be reached for comment as of press time, formulates a policy that will govern our skies.

“The EPA is moving forward,” Wagner said. “And then, on a separate track, some members of Congress are trying to strip the EPA of their power to do so. Nobody has legally stopped them, but attempts are going on right now.”