California seeks to ban sales of diesel big rigs in a bold bid to cut pollution, but has failed to persuade the state’s three leading environmental groups.
The state Department of Environmental Conservation on Monday announced it had filed a motion to ban the use of the most pollutants-polluting type of diesel engines on heavy-duty diesel trucks in California.
The proposed change to state law would make it the first state in the country to ban the use of so-called “smog”-emitting diesels on its trucks. Until now, state law has prohibited trucks from using diesels with more than 30 milligrams of soot per mile, known as particulate matter, or PM10.
But the move would also make California the first state to ban using diesels with more than 30 grams of a chemical known as PM2.5.
The proposed ban would mark a dramatic shift in the state’s trucking emissions program.
The move comes as efforts to fight global warming and curb air pollution have grown by the year, as public support for the measures has grown. Pollution is a leading contributor to global warming, with about a third of the blame for global temperature increases.
The proposed ban, if approved, would affect about 900,000 heavy-duty diesel trucks and buses. The vast majority of California drivers are not affected because federal law prohibits them from operating vehicles with diesels rated over 35 horsepower with the maximum of six cylinders.
Diesel engines are much cleaner than older gasoline engines that preceded them. The U.S. Environmental Protection Agency calculates that diesel trucks emit an average of 13.1 pounds of PM2.5 from a mile of driving, compared to 15.2 pounds for gasoline trucks.
California’s proposed ban is part of a national policy announced this month by the EPA to begin restricting the use of the most toxic diesels on heavy-duty trucks by 2025.
A coalition of environmental groups and the U.S. Conference of Mayors filed a lawsuit against