Battelle’s Web-based System Improves Access to Air Toxics Data

Monitoring 188 toxic chemicals designated as Hazardous Air Pollutants in the 1990 Clean Air Act Amendments has been one of the responsibilities of the Air Toxics Program of the U.S. Environmental Protection Agency’s Office of Air Quality Planning and Standards (OAQPS). OAQPS administers the National Air Toxics Assessment and will expand monitoring under a National Air Toxics Monitoring Network.

Two major projects now underway will greatly enhance public access to a wealth of current air toxics monitoring data:

• Pilot monitoring in four urban areas and six small city/rural areas, and
• Analysis of existing air toxics monitoring data, which is being performed by Battelle Memorial Institute and its subcontractor, Sonoma Technology, Inc., under contract to the Lake Michigan Air Director’s Consortium.

One of the most significant components of the data analysis project has been the development of a Web-based system that can be queried to make the wealth of current air toxics monitoring data accessible through the Internet. A relational database created from the current archive of air toxics data, and an accompanying website provide the general public access to the data.

The volume of observational data in the archive is too large for practical on-line viewing at the individual observation level. However, summaries are available on-line. Any combination of Environmental Protection Agency (EPA) regions, states, counties, monitoring agencies, sites, chemical compounds, date ranges, and data quality parameters can be used to study subsets of data. Users can also:

• Summarize and sort data by EPA region, state, county, or site, and by year, quarter, month, or day; and
• Calculate statistics including mean, standard deviation, minimum, first quartile, median, third quartile, maximum, number of observations, and number of contributing sites.

Results can be viewed on-line in table, chart, or map form. The website dynamically creates line and bar charts of the user's query results (Figure 1) and enables users to download a file containing the results of any requested analysis, using one of three formats: comma separated text, Excel, or dBase.

Basic mapping capability on the website allows users to view a map of the site’s contributing data to a set of query results (Figure 2). The map displays state and county boundaries at appropriate scales and lets the user zoom in, zoom out, and pan the view. Enhancements to the mapping capability figure prominently in future plans.

For more information on Battelle’s Air Toxics Data Archive Data Analysis and website project, please contact Mark Davis at (614) 424-4218, davismd@battelle.org.