Air-quality improvements created by eliminating older cars from Utah roads has just about peaked, and officials believe by 1995, Utah could face new problems related to automobile-caused air pollution.

Alton Frazier of the Utah Bureau of Air Quality told the Utah Energy Conservation and Development Council that this trend could be reversed if Utah adopts California emissions standards for new cars, however. Frazier said the new federal Clean Air Act is likely to make the California standards the norm for the nation. If it doesn't, he believes Utah will move ahead on its own.Officials believe changing to the California standards would stimulate improvement in automobile-related pollution levels for another 10 to 15 years.

Adding to the problem are overcrowded highways. Frazier said higher average speed on highways translates directly into lower pollution levels. He said modern engines are most efficient when speeds average 40 mph or higher. He said below 15 mph, pollution levels are at their worst. Utah's steady population growth is putting more cars on the road and causing average highway speeds to decline, Frazier said.

Also compounding the problem is the tendency for Utahns to keep their cars longer in comparison to other areas of the country.

Frazier said local industries have made significant improvements in their pollution levels. He said with that effort also peaking, emissions from secondary sources such as automobiles become more significant.

Utah's problem is not significant enough to force implementation of special programs such as the use of oxygenated fuels, i.e., fuels that have higher levels of oxygen to produce more complete combustion. Shelly Cordon of the Utah Petroleum Association said adding oxygen to fuels is costly and in some instances affects automobile performance.

Cordon said petroleum producers are actively looking at alternative fuels and will likely play a key role in providing those fuels in the future.