Edison Says Diesel Trains Add to Smog : Transportation: Utility’s study says such engines are less beneficial than cars they replace. Company is lobbying county to electrify commuter rail lines.

Commuter trains pulled by diesel locomotives would create more pollution--twice the amount of one smog component--than all of the automobiles they are projected to take off the freeways, a study commissioned by Southern California Edison Co. asserts.

Local transit officials are skeptical of the report’s assumptions and conclusions, which were given to the California Transportation Commission last week as part of an analysis of electric-powered vehicles.

They acknowledge that the report has given urgency to previously private negotiations between the utility and Los Angeles County Transportation Commission about electrifying 130 miles of commuter train lines the commission plans to open next year.

“The assumption always has been that the more cars you get off the road, the better off you are,” said Richard Schweinberg, manager of electric transportation research at Edison. “Our study indicates this is not necessarily true” for all pollutants.

“What they’ve come up with flies in the face of what has been found in other cities . . . (where), on balance, diesel locomotives are far more beneficial than the cars they replace,” said Richard Stanger, manager of commuter rail trains at LACTC. “Something is strange. Something is wrong and we have to find out what it is.”

The state transportation commission has asked Edison to meet with the county commission and other government agencies on Aug. 20 to review the study’s findings and consider Edison’s tentative offer to pay the $80-million cost of electrifying the commuter rail network.

The LACTC, in cooperation with similar agencies in Orange, San Bernardino, Riverside and Ventura counties, is racing to buy old and marginal freight railroad tracks, upgrade them to passenger standards, and build stations in time to launch commuter service by November, 1992.

Three lines would radiate from Los Angeles Union Station to Moorpark in Ventura County, the Santa Clarita Valley and San Bernardino. Together, they are projected to carry 10,600 passengers a day.

It has been assumed that the lines would ease air pollution by taking a similar number of automobiles off the road. The Edison study confirmed that, compared to cars, the trains would emit 90% less of one class of smog components, reactive organic gases, or hydrocarbons. But the diesel-burning locomotives unexpectedly would double the amount of another pollutant, oxides of nitrogen.

“It would be like adding 11,000 or 12,000 cars to the road” in terms of that pollutant, said Schweinberg. “We were just as surprised as the next guy.”

Oxides of nitrogen put a bourbon tint and fine acidic particles in the summertime air. They also react with hydrocarbons to form ozone, an invisible, sharp-smelling gas that causes lung damage.

Stanger said he still believes that the diesel locomotives will prove cleaner than cars.

“We don’t think those (Edison) numbers are correct,” he said. “Our locomotives have specifically been designed to be more fuel efficient--and therefore put out fewer pollutants--than other locomotives.”