On Monday, the U.S. Environmental Protection Agency ( EPA) and the U.S. Department of Transportation (U.S. DOT) announced the first national standards to reduce greenhouse gas (GHG) emissions and improve fuel efficiency of buses and heavy-duty trucks.

This comprehensive national program is projected to reduce GHG emissions by nearly 250 million metric tons and save 500 million barrels of oil over the lives of the vehicles produced within the program's first five years.

"Through new fuel-efficiency standards for trucks and buses, we will not only reduce transportation's environmental impact, we'll reduce the cost of transporting freight," said U.S. Transportation Secretary Ray LaHood. "This is a win-win-win for the environment, businesses and the American consumer."

EPA and DOT's National Highway Traffic Safety Administration (NHTSA) are proposing new standards for three categories of heavy trucks: combination tractors, heavy-duty pickups and vans, and vocational vehicles. The categories were established to address specific challenges for manufacturers in each area.

Overall, NHTSA and EPA estimate that the heavy-duty national program would provide $41 billion in net benefits over the lifetime of model year 2014 to 2018 vehicles. With the potential for significant fuel efficiency gains, ranging from seven to 20 percent, drivers and operators could expect to net significant savings over the long-term.

The innovative technologies fostered by this program would also yield economic benefits, enhance energy security and improve air quality. New technologies include widespread use of aerodynamic improvements and tire rolling resistance, as well as engine and transmission upgrades.

EPA and NHTSA are providing a 60-day comment period that begins when the proposal is published in the Federal Register. The proposal and information about how to submit comments is here and here.

As part of the process of developing this proposed rulemaking, NHTSA has prepared a Draft Environmental Impact Statement (EIS) for its proposed fuel efficiency standards. The Draft EIS compares the environmental impacts of the agency's proposal with those of a number of regulatory alternatives. Comments may be submitted on the Draft EIS through Jan. 3, 2011, and information on the submission of comments for this document may be found at the NHTSA Web address listed above.