As the year headed into its twilight, the Environmental Protection Agency shocked trucking with the announcement of plans to tighten restrictions on diesel pollution even more than engine makers had agreed to.
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In October, EPA said it would require as early as 2007 that engine makers cut emissions of nitrogen oxides 75% to 90% beyond standards already set for 2004. Emissions of particulate matter would have to be reduced 80% to 90% below current levels.
To make these cuts feasible, EPA said it would call for a dramatic reduction in the amount of sulfur in diesel fuel.
Even with a further reduction in sulfur levels, engine makers said they are unable to meet those lofty goals or even know how attaining the standards would affect fuel economy and truck performance.
For the full story, see the Jan. 10 print edition of Transport Topics. .