EPA Final Rule on Carbon Monoxide Retains Standards, Alters Monitoring

Turn to the nation's most objective and informative daily environmental news resource to learn how the United States and key players around the world are responding to the environmental...

The Environmental Protection Agency announced a final rule Aug. 15 that retains the existing air quality standards for carbon monoxide but changes how states must monitor the pollutant.

The agency said the current primary national ambient air quality standards for carbon monoxide are sufficient to protect public health. EPA also affirmed its decision not to set a secondary standard because carbon monoxide does not directly affect the environment.

The rule alters the monitoring provisions so that states will have to monitor areas near roads in heavily populated areas. The rule requires states to place monitors in areas with more than 1 million people.

EPA estimates that will mean 52 monitors near major roadways around the country. According to the agency, 328 monitors were in place across the country as of May 2011. The rule will not necessarily require additional monitors, as states could reposition existing ones.

EPA said carbon monoxide levels have dropped by 80 percent since 1980 because of emissions controls on vehicles, which are the largest sources of carbon monoxide. No areas of the country are in violation of the standards.

Groups Criticize Standards

The primary air quality standards are 9 parts per million measured over 8 hours and 35 ppm measured hourly. The standards were first set in 1971.

At least two organizations, the American Lung Association and Clean Air Watch, criticized the standards Aug. 15.

Studies have shown that carbon monoxide levels that are below the current standards can harm public health, Charles D. Connor, president and chief executive officer of the American Lung Association, said in a statement.

“Millions of Americans are unprotected by the current air quality standards for carbon monoxide,” Connor said.

The ALA and Clean Air Watch both said EPA ignored advice from the agency's advisory board, the Clean Air Scientific Advisory Committee.

The committee reviewed a draft version of EPA's policy assessment of the rule in June 2010 and said adverse health effects can happen at the current standard, which is why the committee preferred a stricter standard.

Monitors Required in Urban Areas

The monitors must be in place by January 2015 in areas with more than 2.5 million people and by January 2017 in areas with more than 1 million people.

Connor called the placement of the monitors “a critical step to let the public know where unhealthy levels of this dangerous pollutant are in their communities.”

People who are exposed to transportation routes are exposed to pollutants, and a lack of adequate monitoring has meant that they cannot adequately know the threats to their health, he said. It also has limited research and cleanup of the pollutant, he said.

In a final policy assessment of the rule issued in October 2010, EPA staff recommended either retaining the existing standards or potentially strengthening them. If EPA had chosen to set more stringent standards, the policy assessment recommended setting the hourly standard in a range between 5 ppm and 15 ppm and the eight-hour standard in a range between 3 ppm and 9 ppm.

EPA published the proposed rule in February (76 Fed. Reg. 8,158; 21 DEN A-2, 2/1/11).

EPA Administrator Lisa Jackson signed the rule Aug. 12, which was a court-ordered deadline.

Communities for a Better Environment and other environmental groups sued EPA in the U.S. District Court for the Northern District of California, alleging the agency failed to review the carbon monoxide standard every five years as required by the Clean Air Act (Communities for a Better Environment v. EPA, N.D. Cal., No. 07-3678, order issued 5/5/08).

The final rule will be effective 60 days after publication.

By Jessica Coomes

The final rule affirming the primary national ambient air quality standard for carbon monoxide is available at http://tinyurl.com/3gdyog4 .