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EPA Proposes Rule to Cut Nondiesel Engine Emissions

For more information, contact Roger Brower at 410.312.7907.

EPA has proposed new emissions standards and fuel sulfur restrictions for nonroad diesel engines, the largest remaining contributors to mobile source emissions. These engines, used in construction, agricultural, mining and industrial equipment, account for roughly 44 percent of the nation's mobile source diesel PM emissions and 12 percent of the NOx emissions from this source category. The proposal, published on May 23rd, should reduce PM and NOx emissions from nonroad diesel emissions by more than 90 percent. Also, the proposal regulates diesel fuel for the first time, reducing sulfur by more than 99 percent. The proposed emissions standards, to be fully phased in by 2014, will begin affecting new engines in 2008. The proposed fuel sulfur restrictions, taking effect in 2007, will be fully phased in by 2010. Engine manufacturers and fuel refiners will be most affected by these proposed rules.

The Federal Register notice of the proposal can be found at: http://www.epa.gov/EPA-AIR/2003/May/Day-23/index.html

The proposal includes new engine exhaust emissions standards, emissions test procedures, including not-to-exceed requirements, for nonroad engines ranging from 3 to over 3,000 horsepower, as well as sulfur limits for nonroad, locomotive, and marine diesel fuel. Emission standards similar in stringency to the final standards included in the 2007 highway diesel program will begin to take effect for nonroad sources in the 2008 model year, with a phase-in of standards across five different engine power rating groupings. The following table shows the proposed standards and timetable.

* The 3.5 g/hp-hr standard includes both NOx and nonmethane

To meet the proposed emission standards, engine manufacturers will produce new engines with advanced, high-efficiency control technologies, such as catalytic emission control devices. However, these systems require ultra low sulfur diesel fuel to meet the proposed standards. This proposal would reduce the currently uncontrolled sulfur levels for nonroad diesel fuel to an interim cap of 500 ppm beginning June 1, 2007. By June 1, 2010, sulfur levels for fuel used for nonroad diesel applications except locomotive and marine engines would be further reduced to a maximum sulfur level of 15 ppm.

If you have any questions, feel free to contact Roger Brower at 410-312-7907 or rbrower@zephyrenv.com.