The diesel-fueled engine is the backbone of our nation's transportation system, from delivering produce to our local groceries to powering our mass transit systems in our nation's cities and towns. The diesel engine can be as clean, if not cleaner, than any other power source. It is capable of meeting emission standards more than 90 percent below today's levels. And emissions from today's engines have already been reduced by over 90 percent. We recognize that more, much more in fact, can and should be done and we are poised to meet that challenge by the end of this decade.
The key to achieving these future stringent emissions reductions is to reduce the sulfur content of diesel fuel. As the Environmental Protection Agency acknowledged in its proposed rule, future emissions reductions require a systems approach involving the engine, aftertreatment and fuel. Fuel quality, one leg of this three-legged emissions reduction strategy, enables the technologies necessary to make the other two stand.
Without removing essentially all the sulfur from diesel fuel, advanced NOx aftertreatment devices will not be feasible; advanced PM aftertreatment will be poisoned; and engines will be exposed to excessive wear, increased maintenance costs, and impaired durability. I cannot emphasize enough the critical importance of ultra-low sulfur fuel: it enables substantial NOx emission reductions; it provides direct PM emission reductions for every vehicle; and it provides benefits not just from new engines, but from the entire fleet of diesel-fueled vehicles.
Improved diesel fuel also has a role in responding to concerns over potential health effects. Ultra-low sulfur fuel lowers the total mass of particulate from the entire fleet and enables the use of known aftertreatment technologies, such as oxidation catalysts, which can reduce the organic fraction of PM emissions. A rule that calls for ultra-low sulfur fuel also enables the application of catalyst-based technologies to reduce NOx that, in turn, will reduce the secondary formation of fine particles of concern in our urban air.
We applaud EPA for recognizing the critical role of fuel sulfur. We strongly support the need for a uniform, nationwide low sulfur fuel standard with a hard cap on maximum sulfur content. Regional differences in sulfur content will not allow the systems approach necessary to meet EPA's very stringent NOx and PM emission levels. Further, a hard cap on sulfur is critical. Averages simply will not work. They are difficult and impractical to enforce. Moreover, the engine and aftertreatment legs of the stool must be assured of never being exposed to high sulfur fuel.
In our view, a 15 ppm sulfur limit does not go far enough. Our cooperative testing programs have indicated the extreme sensitivity of aftertreatment devices to sulfur poisoning. Therefore, EMA advocates an even lower limit of 5 ppm sulfur in diesel fuel to ensure we are delivering the maximum performance of these devices for the useful life of the truck engine, which is up to 435,000 miles. And, diesel fuel improvements shouldn't only be limited to trucks and buses. Non-road fuels also must be similarly improved.
We are aware of the various arguments raised by the oil industry against improving fuel quality. They don't want to reduce sulfur to even 15 ppm, let alone to lower levels. Nationwide ultra-low sulfur fuel can no, must be achieved, and it can be done cost effectively. In a joint project with the American Petroleum Institute and the National Petroleum Refineries Association, the Engine Manufacturers Association contracted with MathPro, a renown refining consultant, to estimate the cost of producing ultra-low sulfur fuel. MathPro concluded that the typical refining cost to produce a 5 ppm maximum sulfur fuel was from 5« to 9 cents per gallon for the most severe sulfur scenario which modeled a 2 ppm average across the entire diesel pool. Mr. Chairman, we ask that the entire MathPro Study be included with this statement in the hearing record.
So today we are enthusiastic and hopeful about the bright future ahead for diesel engines and our industry's ability to produce reliable, durable, fuel efficient, high performing diesel engines that also are as clean or cleaner than any other power source. There will be issues along the way and a great deal of work to be done. But it is no longer a question of 'IF'. With nationwide ultra-low sulfur diesel fuel and a little development time, engine manufacturers have the resources to achieve the stringent emission goals set forth in EPA's proposal.
I would be pleased to respond to any questions the Subcommittee might have.