Associated Press

GAINESVILLE — Trace levels of contamination from a federally regulated waste site have been detected in the Floridan Aquifer, two miles from the wellfield that draws drinking water for 135,000 residents.

Most groundwater experts, environmental health officials and Gainesville’s publicly owned utility agree that an immediate health threat does not exist.

But they do say more testing is needed to determine the full extent of the pollution at the Cabot Carbon-Koppers site, and additional steps may be required to remove the contamination from the aquifer.

A wood treatment facility has existed at the site since 1916. A two-month investigation of soils and groundwater beneath the Superfund cleanup site concluded that chemicals used in wood preservation — including arsenic, naphthalene, acetone and benzene — had migrated into the aquifer 156 feet below. Prolonged exposure to those chemicals can lead to bone marrow damage, anemia and cancer.

The field investigation was completed in June by TRC, a national environmental engineering firm. It was prepared for Beazer East, a Pittsburgh-based company that briefly owned the site and is now responsible for its cleanup.

The chemicals detected were found in relatively low concentrations — arsenic, for example, was measured as high as 30 parts per billion. Federal drinking water standards currently limit arsenic to 50 parts per billion, although public water systems will need to comply with a 10 ppb standard starting January 2006.Still, the discovery of harmful pollutants so close to Gainesville’s drinking water source is alarming, officials said.

“It’s gotten our attention,” said Kim Zoltek, director of water and wastewater for Gainesville Regional Utilities.

The site lies within the “capture zone” for the Murphree Wellfield, where 15 wells take water from the Floridan two miles northeast of the Superfund site, said Brett Goodman, the utility’s senior environmental engineer for water and wastewater.

Eventually, all groundwater within the “capture zone” has the potential to be sucked from the Murphree’s pump stations, although that could take years or decades, he said. Two monitoring wells have already been drilled between the wellfield and the Koppers site, and eight to 10 more are planned.

The U.S. Environmental Protection Agency recognized the site as a national Superfund priority in 1983, a designation that earmarks federal resources for cleanup of the country’s most-polluted sites. Cleanup of the site began in the early 1990s.

“The fact that we have now detected these chemicals in the Floridan under the site, that is going to require a whole new look for the cleanup operation,” said Chris Bird, director of the county’s environmental protection department.