Illinois Annual Air Quality Report

Illinois Annual Air Quality Report 2008

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A Message from the Director

Air quality is an important issue for all Illinois residents, especially those with chronic lung and heart disorders. Since the creation of the Illinois EPA in 1970, we have learned a great deal about what is in the air we breathe and what we can do to make the air cleaner. The Illinois EPA focuses on many issues, but providing a healthy, clean environment for Illinois citizens has always been and will continue to remain a top priority.

The 38th Annual Air Quality Report provides a summary of air quality data collected in calendar year 2008. The Agency monitors air quality for numerous pollutants including particulate matter, ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide and lead. Recent improvements in technology have also allowed the Agency to collect data on some heavy metals (mercury), nitrates, sulfates and volatile organic compounds.

Data collected in 2008 was similar to past years. Air quality ranked "good" or "moderate" 96 percent of the time throughout the state. This compares to 93 percent in 2007 and 97 percent in 2006. Overall, air quality trends continue to be below the national standards.

As technology advances we continue to improve the way we evaluate air quality. Through our monitoring network, air quality is sampled from more than 80 individual sites including schools, businesses, fire stations and independent trailers. Additionally, we are now able to see some air quality data in real-time. Tremendous progress has been made over the past few decades, and we are looking forward to gaining more knowledge to continue air quality improvements and better protect the public in the future.

The Illinois EPA strives to provide a healthy environment for all citizens. Data is not only collected and analyzed, but is provided on a daily basis through the Agency’s website. The information offered to the public daily can be critical to individuals suffering from lung and heart disorders. The Illinois EPA will continue to provide this essential service and predicts further improvements in air quality in years to come. If you have any questions and/or comments regarding the 2008 Annual Air Quality Report or air pollution control programs, please feel free to contact the Illinois EPA.

Douglas P. Scott
Director

Executive Summary

This report presents a summary of air quality data collected throughout the State of Illinois during the calendar year - 2008. Data is presented for the six criteria pollutants (those for which air quality standards have been developed - particulate matter (PM10 and PM2.5), ozone, sulfur dioxide, nitrogen dioxide, carbon monoxide, and lead) along with some heavy metals, nitrates, sulfates, volatile organic and toxic compounds. Monitoring was conducted at over 80 different site locations collecting data from more than 200 instruments.

In terms of the Air Quality Index (AQI) air quality during 2008 was either good or moderate 96 percent of the time throughout Illinois. There were no days when air quality in some part of Illinois was considered Unhealthy (category Red). This compares with one Unhealthy day in 2007. There were 14 days (10 for PM2.5 and 4 for the new 8-hour ozone standard) when air quality in some part of Illinois was considered Unhealthy for Sensitive Groups (category Orange). This compares with 24 Unhealthy for Sensitive Groups days reported in 2007. However, based on the new ozone and PM2.5 AQI adjustments implemented in 2008 there would have been 45 Unhealthy for Sensitive Groups days in 2007. Air quality trends for the criteria pollutants are continuing to show downward trends or stable trends well below the level of the standards. Percentage changes over the ten year period 1999 - 2008 are as follows: Particulate Matter (PM10) 14 percent decrease, Particulate Matter (PM2.5) 20 percent decrease, Sulfur Dioxide 15 percent decrease, Nitrogen Dioxide 13 percent decrease, Carbon Monoxide 47 percent decrease, Lead 18 percent decrease, and Ozone 12 percent decrease.

Stationary point source emission data has again been included. The data in the report reflects information contained in the Emission Inventory System (EIS) as of December 31, 2008. Emission estimates are for the calendar year 2008 and are for the pollutants: particulate matter, volatile organic material, sulfur dioxide, nitrogen oxides and carbon monoxide. Emission trends of these pollutants have been given for the years 1998 to the present. Emissions reported with the Annual Emissions Report have been provided starting with 1998 and are currently available through 2007. In general there has been a trend toward decreasing emissions over this time period.