The U.S. Environmental Protection Agency is awarding $30 million for clean diesel projects as part of its Diesel Emission Reduction Program, the agency announced.
The money will go to replacing and retrofitting older diesel powered engines in trucks, buses and locomotives, EPA said.
Winners of the grants were selected based on the potential for maximizing health and environmental benefits in areas with significant air quality issues.
According to EPA, there are more than 11 million older diesel engines still in use in the United States.
The agency has awarded more than 500 grants nationwide through the program since it was first funded in 2008.