EPA proposes reduction of sulphur in diesel

The reduction, which would set a limit of 15 ppm for sulphur, has been opposed by the US fuel industry, which has lobbied for the limit to be dropped from 500 ppm cap to a new cap of 50 ppm (see related story).

The EPA plans to finalise the standards by the end of the year and for them to take effect in mid 2006.

Like last year’s proposal for cleaning emissions from cars (see related story), the programme requires US diesel truck and bus manufacturers to install pollution control devices such as catalytic converters. The reduction in sulphur is required because sulphur damages these converters, preventing them from removing pollutants from the fuel.

Truck manufacturers would have to introduce pollution prevention technology in 2007. All new heavy vehicles would have to meet the standards by 2010.

Together, the measures proposed by the EPA are designed to cut emissions from heavy trucks and buses by to up 95% – the equivalent of eliminating air pollution from 13 million lorries from US roads.

If fully implemented as proposed, the programme will reduce emissions of NOx and non-methane hydrocarbons (NMHC) by 2.8 million and 305,000 tons per year in 2030, respectively. Particulate emissions from these vehicles would be reduced by 110,000 tons per year by 2030.

But the US fuel industry says the proposal could lead to problems with the supply of diesel. “This extreme proposal is a blueprint for future supply problems,” said the National Petrochemical & Refiners Association (NPRA). “It will reduce the supply of highway diesel because many refiners will be unable to bear the heavy costs of reducing sulphur to the unrealistic level chosen by EPA. Supplies of home heating oil and gasoline will also be affected if and when refineries close or reduce capacity because of the crushing investment burden,” said NPRA President Urvan Sternfels.

Meanwhile, state and local air quality regulators welcomed the proposal. “This proposal confronts noxious air pollution from diesel trucks straight on and could prevent tens of thousands of cancers. We give it two thumbs up,” said S. William Becker, executive director of the State and Territorial Air Pollution Program Administrators and the Association of Local Air Pollution Control Officials (STAPPA/ALAPCO). “EPA is right on the mark in proposing a rigorous ‘systems approach’ that addresses both the diesel engine and its fuel. We look forward to final issuance of this rule before the end of the year so that we can move forward with this important program,” said Becker. “We also urge the Agency to make cleaning up diesel engines and fuel used in construction equipment and for other non-highway purposes a top priority. As significant a source of air pollution as diesel trucks are, big ‘nonroad’ diesels are even more significant.”