8 September 2001

According to press reports (AP), the US EPA has rejected three petitions by the industry to reconsider the 2007 heavy-duty diesel engine emission standards and fuel sulfur regulation. The petitions came from the American Petroleum Institute, the American Trucking Association and Mack Trucks/Volvo Powertrain.

The 2007 standards were finalized in December 2000 and re-confirmed by the Bush administration in February 2001.

The standards establish emission limits of 0.01 g/bhp-hr PM (currently 0.1 g), 0.20 g/bhp-hr NOx (currently 4 g), and a 0.14 g/bhp-hr limit for NMHC. The PM emission standard will take full effect in the 2007 heavy-duty engine model year. The NOx and NMHC standards will be phased in for diesel engines between 2007 and 2010. The phase-in would be on a percent-of-sales basis: 50% from 2007 to 2009 and 100% in 2010. Diesel fuel of maximum 15 ppm sulfur (currently 500 ppm) will be required beginning mid-2006.

Since the beginning of the rulemaking process, the 2007 standards have been subject of intense industry lobbying. The fuel rule is strongly opposed by a part of the petroleum industry, while the emission standards are opposed by some engine manufacturers (but supported by others). The National Petrochemical and Refiners Association (NPRA) filed a litigation to challenge the EPA diesel fuel rule, claiming it would threaten consumers with cost increases and significant shortages in diesel fuel supplies.

The 2007 regulation is a “technology forcing” standard, which would require the use of diesel particulate filters and NOx reduction catalysts on new heavy-duty engines. These exhaust aftertreatment technologies, especially the NOx catalysts, are not yet commercially available and would have to be developed by the 2007 deadline.