Three years after state officials said a pesticides formulation factory site should be a top priority for investigation, the Environmental Protection Agency is planning to clean it up.

The site is Wasatch Plaza, 2225 S. Fifth East, where pesticides were made for half a century starting in 1920. In March 1986, a private study showed high levels of pesticide there and in the surrounding residential neighborhood."We have targeted this for a fast-track site investigation," Loretta Pickerell, Utah's Superfund program manager, said at the time.

This month the EPA announced it is developing plans for a removal action there. A day-care center is east of the two-acre lot and a school lies to the west, across the street.

A fact sheet developed by the EPA and state health officials says soil near the chemical company's old loading dock is contaminated with organic chemicals, mostly DDT. Probably the contamination happened when chemicals spilled during loading, before the company left the site in 1971, it says.

Most of the property is paved over with asphalt or has had buildings constructed on it. The exception is an alley to the south of the buildings, about 50 feet wide and 750 feet long, which is divided by a spur of the Denver & Rio Grande Western Railroad.

"The voluminous data that exists from samples collected on and near the site indicate that alley soils are contaminated with approximately 50 different toxic chemicals," says the fact sheet. "The chemicals of concern include a variety of chlorinated pesticides, herbicides, organic chemicals, dioxins and furans."

Many of these dangerous chemicals are long-lasting in the environment.

Children could be exposed to the chemicals if they ate soil from the site, and others could be exposed if they inhaled soil kicked up by wind or traffic, or breathed in vaporized chemicals.

"The people most likely to be exposed to the contaminated soil include children playing, visiting or passing near the site, and individuals who work at the site," the report says.

A risk assessment prepared by EPA toxicologist Dr. Robert Benson recommended removing any soil contaminated with DDT at a concentration greater than 7,600 parts per billion. Water appears to have no significant contamination, however.

In early June, the EPA will collect soil samples to decide how deep the agency must excavate to clean up the soil with enough contamination to be of concern. Samples of the soil will be submitted to certified toxic waste disposal facilities.

Later, soil will be dug out of the alley and sent to the disposal area.