Last Friday, the District of Columbia Circuit Court of Appeals upheld a rule by the US EPA (Environmental Protection Agency) that will force heavy-duty trucks and buses in the US to run a lot cleaner in 2007.
The regulation requires reduced emissions from diesel trucks and buses and lower sulphur levels in diesel fuel.
The court rejected all arguments raised by the petitioners, including the engine maker Cummins, who claimed that advanced after-treatment technologies would not be available in time.
The court also rejected claims that the level of sulphur 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 in the US will be reduced by 95%. Sulphur 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% reduction in the sulphur content of highway diesel fuel from its current level of 500 parts per million to 15 parts per million.
Specifically, to achieve the drastic reductions in particulate matter (PM), nitrous oxides (Nox), and non-methane hydrocarbons, engine manufacturers will need to adopt technical innovations in emission controls. The EPA predicts that two relatively new technologies will aid in achieving the 2007 reductions: the catalysed diesel particulate filter (‘particulate filter’) and the Nox adsorber.
Reduced levels of sulphur in diesel fuel are also 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. Soot or particulate matter will be reduced by 110,000 tons a year.
The EPA estimates that more than 360,000 asthma attacks and 386,000 cases of respiratory symptoms in asthmatic children will be avoided every year. In addition, 1.5 million lost work days, 7,100 hospital visits and 2,400 emergency room visits for asthma will be prevented.
The court’s opinion is available at: http://pacer.cadc.uscourts.gov/common/opinions/200205/01-1052a.txt