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Stronger rules for diesel engines to be discussed at Denver public hearing

Release Date: 6/28/2000
Contact Information:
EPA 303-312-7094,

Release Date: 6/28/2000
Contact Information:
EPA 303-312-6446,

Release Date: 6/28/2000
Contact Information:
EPA 303-312-6603

      DENVER– The U.S. Environmental Protection Agency will hold a public hearing tomorrow on its proposed program to strengthen emission standards and require cleaner-burning diesel fuel for heavy-duty trucks and buses. The hearing is in Denver starting at 10 a.m. on Thursday, June 29, at the Doubletree Hotel – 3203 Quebec Street.
The proposed diesel rule is a major milestone in our nation’s drive toward clean air, comparable to the advent of catalytic converters on cars in the 1970s. By addressing diesel fuel and engines together as a single system, the proposal would reduce harmful, smog-causing emissions from trucks and buses by 95 percent of current levels – the clean-air equivalent of eliminating air pollution from 13 million of today’s trucks. Meanwhile, soot emissions would drop by 90 percent of current levels. The result will be diesel-fueled vehicles that are as clean as today’s low emissions vehicles, which translates to much healthier air for all Americans.

Heavy-duty trucks and buses are largely powered by diesel engines, which are more durable and get higher fuel economy than gasoline engines, but also pollute much more. Harmful emissions from these engines greatly add to many serious air pollution problems and will continue to without further plans to curb them.

If approved, the new emission standards will take effect progressively beginning in 2007 with full compliance by 2010. New trucks and buses would be required to meet standards. This means that, for the first time ever, heavy-duty trucks and buses could use pollution-control devices to meet emission standards, just as passenger cars have done for the past 25 years. These devices are sensitive to sulfur and will not work unless the amount of sulfur in the fuel is dramatically reduced. Therefore, by June 2006, EPA will require a new diesel-fuel formula that caps the sulfur content at 15 parts per million (ppm) – 97 percent less than the current cap of 500 ppm.

Diesel emissions contribute to many air pollution problems, including: ozone (smog), small particles (soot), nitrogen and sulfur oxides, volatile organic compounds, and toxic compounds, such as formaldehyde and benzene. Human exposure is widespread, particularly in urban areas. And, according to several national and international agencies, evidence is mounting that diesel exhaust or diesel particulate matter (soot) may cause lung cancer in humans. Routine exposure to these pollutants can increase the risk of premature death or other health impacts, such as breathing problems, heart disease and persistent bronchitis. Pollution from diesel vehicles also contributes to crop and forestry losses, visibility impairment in many parts of the U.S. and acidification of ground water and surface water.

This proposal is the culmination of a year-and-half long deliberative process where EPA met with a wide range of affected groups to understand their concerns and ensure their issues are fairly addressed in the proposal. Those meetings involved the manufacturers of diesel engines and emissions controls, the fuel industry, trade associations, individual companies, state and local governments, public health experts and environmental groups.

To assure the fuel supply is not disrupted, EPA designed this proposal to include plenty of lead time for the introduction of the new, cleaner diesel fuel into the marketplace. The proposal also discusses various flexible phase-in approaches for the diesel-fuel industry to help ease the transition to the new fuel and to further reduce costs. EPA believes its diesel rule addresses the many issues raised so far, and it can achieve dramatic emission reductions in a cost-effective manner – without placing large burdens on small businesses and consumers.

The hearing is the last of five held nationwide this month by EPA to get comments from all affected groups. Following the public hearings, there will be a 45-day comment period. EPA will continue to meet with stakeholders on an individual basis to better understand their concerns and suggestions. The Agency plans to complete this process and issue final requirements by the end of this year.

The proposed rule and related documents are available electronically via the EPA Internet site at: EPA will accept written comments through August 14, at the address below:

Margaret Borushko
USEPA National Vehicle and Fuel Emissions Laboratory
2000 Traverwood
Ann Arbor, MI 48105
Fax: (734) 214-4816

EDITOR’S NOTE: National and regional EPA representatives will be on-hand to answer questions about the proposal. EPA staff will be available to talk with the media beginning at 9 a.m. in the Colorado III Ballroom (some staff also may be available during the lunch break).