A report published last month by the Federal Highway Administration cited a school bus retrofit program run in Massachusetts as an example of an effective use of federal funds from the Congestion Mitigation and Air Quality program.

The program is administered by the Massachusetts Executive Office of Transportation, the Massachusetts Department of Environmental Quality and the Executive Office of Energy and Environmental Affairs and is still underway. But when the diesel oxidation and crankcase filter retrofits are completed, it will reduce the emission output of the state’s entire fleet of 7,800 school buses. The program utilized the EPA’s diesel emissions quanitifier model to esimate that carbon monoxide and hydrocarbon levels will be reduced by 80 percent and that particulate matter will be cut by 25 percent.

The CMAQ Evaluation and Assessment study, required by SAFETEA-LU, determined that the Massachusetts school bus retrofits is a good example of have a statewide CMAQ program that can influence other activities and programs across multiple metropolitan planning organizations.

And the air quality benefits can be realized at relatively low costs. The estimated cost to reduce a kilogram of CO is about $30, while HC reduction is estimated at $597 per kilogram.