The majority of air pollution exceedances recorded in Iowa over the past five years occurred in Muscatine, with sulfur dioxide pollution the primary issue there and statewide.
The five-year assessment of Iowa's ambient air monitoring network operated by the Iowa Department of Natural Resources is required by the U.S. Environmental Protection Agency (EPA) in order to identify areas where air quality does not meet health standards.
The National Ambient Air Quality Standards (NAAQS) network also is designed to alert the public about air pollution levels that may threaten their health. A "NAAQS exceedance" occurs when air pollution exceeds the threshold level where adverse health effects occur among "sensitive groups," including asthmatics, children and the elderly.
The report also provides a preview of how tighter ozone pollution standards expected to be put in place this fall could impact the state.
The EPA has proposed a range for NAASQ ozone levels of between 65 and 70 parts per billion (ppb). Based on a level of 65 ppb, four locations in Iowa would be in violation of the standards: two sites near Pisgah, one location in Clinton (Rainbow Park) and one near Lake Seguma. At the 70 ppb level, no Iowa sites would be in violation.
Muscatine's largest source of pollution, Grain Processing Corporation, was fined a record $1.5 million and ordered to cut air pollution emissions under a consent decree issued in March 2014 which settled a lawsuit filed by the Iowa Attorney General's office.
The Muscatine firm, owned by Kent Corporation, announced a $100-million capital improvement program for the GPC plant after the lawsuit was filed, and promised the plant upgrades will reduce air emissions "well below the newest and more stringent air quality standards now set by the EPA."
The company also said when its new corn-drying facility is complete, "smoke, odor, and haze will be nearly eliminated" at the facility.
CLICK HERE to download a copy of the five-year NAAQS network assessment.
