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Tri-State Geographic Initiative -Air Toxics Modeling Project
Studying air toxics is a major component of the Tri-State Geographic Initiative. The Air Toxics Modeling Project is being conducted in conjunction with the Air Toxics Monitoring Project. The purpose of the Air Toxics Modeling Project is to predict the levels of air pollutants in areas where people live, work, and play by using sophisticated computers.
Air dispersion models are computer programs that can predict where air emissions go after being released. Information about emissions coming from a facility from smokestacks, vents, and other sources is fed into a computer along with information about local weather conditions. The air dispersion model can then determine how the emissions will move and spread throughout the area.
Air dispersion models can provide information that air models cannot. They can predict the average concentrations of any released pollutants at any given location. Air monitors, on the other hand, can only measure pollutants that that occur at that particular monitor. Air dispersion models can provide information concerning the concentration a pollutant is likely to reach. Air monitors can only measure the concentration on the day the monitor collects a sample. Most importantly, air dispersion models provide information needed for risk management (for example, indicate what facility released a particular pollutant in unacceptable amounts).
Air dispersion models are not perfect. A model's prediction for one day may not exactly match the measurements at air quality monitors for that day. But the models are still fairly accurate at indicating where the highest concentrations are most likely to be and how high they are likely to reach. This information is very useful when estimating whether people could be at risk.
The Tri-State Geographic Initiative's Air Modeling Workgroup developed an air Monitoring Workplan. As part of this plan, a new air dispersion model called Calpuff is being used in the Tri-State Geographic Initiative. The Calpuff model is especially good at predicting the movement of air pollution in river valleys like the Big Sandy and Ohio river valleys. The Calpuff model can predict the highest concentration of chemicals that could occur in the area. It will also predict the highest concentrations that could occur at locations such as local schools, daycare facilities, and nursing homes, where sensitive populations are present.
The model will be run for each industrial cluster where the Air Monitoring Project is conducted. Facilities located in the clusters will be asked to provide information about the kind of chemicals released, the locations in the plant where the releases occurred, and the amounts that were released. Companies are required by law to make some information available to the public about their chemical releases. These facilities will be asked to voluntarily provide more information than is required by law. This information will be input into the Calpuff model to predict the air quality for the Tri-State region.
Air Toxics Modeling Project Workplan
Kenova Cluster Air Toxics Project
Greenup Cluster Air Toxics Project