Fine particulate matter pollution in Iowa exceeded national air quality standards at 34 locations during 2009, including six instances in Muscatine, five in Davenport and five in Clinton.
The National Ambient Air Quality Standard (NAAQS) for PM 2.5 (particulate matter 2.5 micograms or less) is a 24-hour average of no more than 35.4 micrograms per cubic meter. The NAAQS represents the U.S. Environmental Protection Agency's best estimate of the threshold for adverse health effects.
The 34 exceedances statewide for PM 2.5 compares to 25 instances in 2008 and 44 in 2007.
Three of the highest readings in Iowa occurred at the Garfield Elementary School monitor near Grain Processing Company (GPC) in Muscatine. The monitor recorded a concentration of 74.4 on December 9, 54 on January 3 and a 52.5 reading November 23.
The location, date and exceedances in Davenport were: Blackhawk Foundry monitor, November 23, 40.1; Jefferson Elementary monitor, November 23, 38.4; Jefferson Elementary monitor, December 21, 37.5; Adams Elementary monitor, December 21, 39.1; Blackhawk Foundry monitor, December 21, 37.8. All readings are in micrograms per cubic meter.
The date and exceedences in Muscatine (all were at the Garfield Elementary School monitor) were: January 3, 54; February 26, 35.7; April 4, 37.3; November 23, 52.5; December 22, 74.4; December 24, 39.6.
The location, date and exceedences in Clinton were: Chancy Park monitor, January 22, 40.7; Rainbow Park monitor, January 22, 40.3; Chancy Park monitor, November 23, 45.5; Rainbow Park monitor, November 23, 46.5; Rainbow Park monitor, December 21, 36.2.
The Quad Cities region (Scott, Rock Island and Muscatine counties) narrowly avoided being classified as in "non-attainment" for PM 2.5 emissions last year by the EPA. Only by being allowed to submit newer 2008 data last January was the EPA's initial finding of "non-attainment" changed to attainment last fall.
Last week, the Iowa DNR issued two air quality alerts for PM 2.5 air pollution in eastern Iowa, including readings above the 35.4 standard in Muscatine, Davenport and Clinton.
The Iowa Department of Natural Resources says the new 2009 PM 2.5 data is still being compiled and won't be submitted to the EPA until April.
For the complete exceedance report of air quality standards in Iowa, click here.
