The Environmental Protection Agency (EPA) and the Office of Management and Budget (OMB) are jointly drafting rules to cut exhaust emissions from diesel-powered equipment used in off-road settings.
The proposed rules would require engine makers to include components to trap and treat exhaust gases, and would require the use of low-sulfur diesel fuel.
Groups supporting the move include the Natural Resources Defense Council, the American Lung Association and the Clean Air Trust. They argue that the proposed rules would cut diesel emissions from off-road sources by as much as 95%. However, several environmental groups have accused the EPA and OMB of giving in to industry pressure to extend the implementation date of the new rules by two years, to the year 2010, and to create a credits-training program for emissions.
EPA officials said they are weighing a two-step approach the industry favors that would reduce the sulfur content of fuel by 2007 and put off the new full implementation of the standard until 2010, giving diesel-engine makers two more years to meet the requirements.
Diesel fuel now used in off-road equipment contains sulfur in relatively high concentrations of 3,000 parts per million.
The original EPA proposal requires refineries to reduce sulfur content of their fuel to 15 parts per million by 2008 and requires engine makers to incorporate trap-and-treat equipment between 2009 and 2012.
Early in 2001, EPA approved a Clinton Administration rule mandating cuts of up to 95% in emissions of particles and nitrogen oxides from large diesel-fueled buses and trucks. The rule has been upheld and will kick in starting in 2007.
