Regional air quality officials approved a measure requiring use of low-polluting diesel fuel in much of Southern California, but backed down from a more aggressive plan that had drawn opposition from the trucking industry and state regulators.
The new rule is the South Coast Air Quality Management District's first attempt to regulate the fuel that powers California commerce but causes vehicles to belch black smoke. It would require refiners in the Los Angeles region to produce diesel fuel containing 90% less in sulfur compounds than today's blends, beginning in 2005.
But under pressure from Gov. Gray Davis' administration and the state's trucking lobby, the air district's governing board included an escape clause that could delay use of the cleaner fuel. Under the escape clause, the new requirement will not go into effect unless the state mandates clean diesel across California. State officials expect to take that step effective in 2006.
Even though the effect of that probably will be to delay the new requirements, local smog fighters say they hope their vote to start the new fuel in 2005 will push the state and federal governments to move quickly on cleaner diesel.
The trucking industry, oil companies and the California Air Resources Board argued that a separate fuel recipe just for a local market could lead to price spikes and fuel interruptions.
"Because this diesel will be the product of only a few refiners, even a small glitch will threaten supply and that threat will send prices through the roof," said Bob Sulnick, director of the South Coast Clean Air Partnership, a coalition of transit agencies, school districts and oil companies opposed to an early introduction of low-polluting diesel fuel.
"With that prospect, and good old reliable diesel being sold just outside the district's boundaries, trucking companies will be fueling up outside before driving in to make deliveries and pickups."
Officials of the state Energy Commission and Air Resources Board expressed similar concerns in a July 17 letter to the local clean-air agency. The letter called a 2004 date (originally sought by the AQMD) for introduction of so-called clean diesel "unnecessary and extremely risky," and Michael P. Kenny, the head of the state air board, had threatened to veto the regional rule if it included the early date.
Environmentalists, however, say the local air quality agency missed an opportunity to press more aggressively to clean up smoggy Southern California.
"They blinked," said Julie Masters, attorney for the Natural Resources Defense Council. "It's based on heavy lobbying pressure from the California Trucking Assn. and the diesel industry. It's very disappointing."
Postponing the date for starting the clean diesel will cause the Los Angeles area to miss a 2006 deadline in the Clean Air Act for reducing the amount of microscopic airborne particles in the region's air. Diesel engines produce about 24 tons of soot daily in Los Angeles, Orange, San Bernardino and Riverside counties.
Diesel exhaust draws frequent complaints from motorists and contains toxic chemicals. About 70% of the cancer risk associated with breathing air in Southern California comes from compounds released by diesel-powered trucks, buses and cars, according to a study by regional air quality regulators.
Under the new regulation, diesel fuel would not be allowed to have a sulfur content of more than 15 parts per million. Cleaner fuel allows vehicles to use particle traps that capture even more soot. Oil companies can expect to pay an additional 2 cents per gallon to produce the new fuel, according to AQMD officials.
The diesel rule is part of an effort by regional officials, who traditionally have regulated smokestacks and other stationary sources, to expand their authority over vehicles, which create most of the smog in Southern California.
Even with the delayed date, the rule is the most stringent diesel control measure in the nation, said Barry Wallerstein, executive officer for the local air agency.