Truck and engine manufacturer Navistar Inc. is challenging U.S. EPA rules aimed at curbing diesel emissions.
Illinois-based Navistar has asked the U.S. Circuit Court of Appeals for the District of Columbia to review EPA's 2001 pollution standard for new motor vehicles' emissions as well as guidance issued in February allowing manufacturers to meet the standard using selective catalyst reduction (SCR) technology.
EPA's 2001 rule requires heavy-duty diesel engines to meet an emission standard of 0.20 grams of nitrogen oxide (NOx) per brake horsepower-hour. The rule is slated to be fully implemented by model year 2010.
When EPA issued the rule in 2001, the agency said SCR technology, which is already widely used to control NOx from industrial plants and other stationary pollution sources, would not be available to meet the standard. But the 2009 guidance document approved SCR technology, amending its 2001 determination that the technology was infeasible.
In a May petition to the court, Navistar questioned whether the 2009 guidance violated the Clean Air Act because EPA failed to submit to a rulemaking procedure before reversing its SCR determination.
SCR technology uses a NOx reducing agent, usually ammonia or urea, to slash NOx emissions by as much as 90 percent. The technology requires regular replenishment of the reducing agent to reduce NOx emissions.
Navistar has said it would meet the stringent 2010 emissions standards for all its core applications without using SCR systems.
Navistar spokesman Roy Wiley declined to comment on the matter because litigation is pending.
Frank O'Donnell, president of the advocacy group Clean Air Watch, called the lawsuit a "Hail Mary pass" by Navistar, which he said opted to use a less expensive pollution control technology and is now trying to delay the standards. "It's appalling that Navistar would be spending on lawyers rather than improving its technology," he said.
Click here to read Navistar's statement of issues to the court.
Click here to read the petition to review EPA's February guidance.
Click here to read the petition to review the 2001 standard.