EPA says it's not anti-SCR

The Environmental Protection Agency (EPA) said the trucking industry incorrectly perceives that the EPA is dead set against allowing Selective Catalytic Reduction (SCR) aftertreatment technology to help trucks meet 2007 exhaust regulations. Karl Simon, a deputy for EPA's Office of Transportation and Air Quality, said the agency is more worried about potential economic and safety issues surrounding SCR than the technology itself, which has been proven on heavy trucks in Europe. However, as those other issues have not been adequately addressed to date, SCR should take a back seat behind other aftertreatment options, he said. Speaking at the American Truck Dealers annual convention, Simon said many technologies remain in play to help engine makers meet the 2007 regulations, including SCR. "Our concern when it comes to SCR isn't so much how it works as how it's supported in the field," he explained. "There are safety and economic issues here." As SCR uses urea sprayed into the exhaust stream to reduce oxides of nitrogen (NOx), truckers will need to be able to obtain urea easily across the U.S. However, Simon noted, it is not clear if that will be the case. Also, Simon said if a truck runs out of urea while on the road, the EPA doesn't want it to keep operating and thereby release pollution into the air, but it also doesn't want it to shut down at highway speed. "That's one reason why the NOx standards are being gradually phased in between 2007 and 2010, because there are different technologies in play -- including SCR," he said. "We'll see how it improves the closer we get to 2007."