The U.S. Environmental Protection Agency is removing another 474 older-model diesel school buses from the nation’s roads.

The EPA announced 138 awards tied to the Diesel Emission Reduction Act rebate program on Tuesday. The school districts and bus contractors located across 40 states are sharing nearly $10.5 million in grant funds to scrap buses powered by model-year 2006 and older engines.

Bus operators submitted applications starting last October to offset the purchase of a 2017 or newer school buses. The lowest award amount was $20,000 for diesel or gasoline school buses, $25,000 for propane buses, $30,000 for compressed or liquefied natural gas, and $65,000 for battery electric.

Suffolk Transportation on Long Island, New York, received the largest grant at $400,000. The contractor has a growing fleet of electric school buses for local school district customers like Bayshore Central School District. Director of Transportation Richard Gallagher spoke about the district’s experiences during day one of the virtual Green Bus Summit on Tuesday.

The smallest award was $16,810 to Winkle Bus Co. of W.H., Inc., in Connecticut.

The vast majority of awards, 111, went to public school districts. Thirty-four contractors received awards, with one company awarded for two different contracts. Three charter schools also won grants.

Since 2012, the DERA rebate program has awarded over $56 million to remove over 2,000 diesel school buses from service.