(CN) - Federal environmental regulators must step in and create plans for 11 states to reduce their levels of sulfur dioxide air pollution, the Environmental Protection Agency said Friday.
The EPA found that nearly a dozen states - Arizona, Iowa, Kentucky, Louisiana, Michigan, Montana, New Hampshire, Ohio, Pennsylvania, Tennessee and West Virginia - have not created plans, as required under the Clean Air Act, to reduce the levels of sulfur dioxide air pollution in certain areas. The plans were due on April 4, 2015.
Exposure to sulfur dioxide, which almost entirely comes from coal-fired power plants, can cause trouble breathing, trigger asthma attacks, and send people to the hospital for respiratory emergencies, the EPA said.
Revisions to the National Ambient Air Quality Standard were promulgated in 2010 by the EPA, which set the maximum concentration for sulfur dioxide at 75 parts per billion. Areas that have sulfur dioxide levels that exceed these public health standards are considered nonattainment areas.
In October 2013, the agency identified 29 areas in 16 states with unsafe levels of sulfur dioxide. The states were ordered to develop state implementation plans for the nonattainment areas.
The EPA said Thursday that nearly two and a half years later, only a handful of the states have complied. The 11 states that have not complied have 16 areas among them that are designated as nonattainment areas.
Noncompliance means the agency must now step in and draft federal plans for the states "to protect these communities exposed to dangerously high levels" of sulfur dioxide.
The 11 states must meet the National Ambient Air Quality Standard for sulfur dioxide by Oct. 4, 2018. Sanctions will be applied in 18 months and again in 24 months if the affected states have not submitted complete plans.
Mary Anne Hitt, director of Sierra Club's Beyond Coal Campaign, said that the EPA's announcement is a "wake-up call for hundreds of thousands of Americans."
"Eleven state governments are stonewalling and making excuses when it comes to protecting the health of our communities, so it's more important than ever that the EPA step up and do its job to promptly put in place federal plans that restore clean air expeditiously," Hitt said.
Hitt encouraged the EPA to "move swiftly" to clean up the air in these areas, which she said are "plagued with high rates of asthma and other health problems triggered by sulfur dioxide air pollution."
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