An Environmental Protection Agency (EPA) rule to make heavy-duty trucks and buses run cleaner has been upheld by the District of Columbia Circuit Court of Appeals, according to EPA. The regulation requires reduced emissions from diesel trucks and buses and lower sulfur level in diesel fuel.
The court rejected all arguments raised by the petitioners, including claims that the advanced after-treatment technology would not be available, according to EPA. The court also rejected claims that the level of sulfur control to 15 parts per million required by the rule was not needed to enable this technology and that it would result in supply shortfalls of diesel fuel.
Beginning with model year 2007, emissions from heavy duty diesel trucks and buses will be reduced by 95 percent. Sulfur in diesel fuel must be lowered to enable modern pollution-control technology to be effective on these trucks and buses. The program requires a 97 percent reduction in the sulfur content of highway diesel fuel from its current level of 500 parts per million to 15 parts per million.
The use of advanced after-treatment technology similar to catalytic converters used on cars today will be installed to achieve the cleaner emission standards. Reduced levels of sulfur in diesel fuel are needed to facilitate the introduction of this technology.
When the rule is fully implemented, 2.6 million tons of smog-causing nitrogen oxide emissions will be reduced each year, according to the EPA. Soot or particulate matter will be reduced by 110,000 tons a year.