Superfund cleanup awaits more data New remedy at former Union Chemical site to be evaluated this month

HOPE – Environmental Protection Agency officials will be looking for good news later this month when they gather soil and water samples at the former Union Chemical property.

The property, designated a federal Superfund site, was once the home of a company that manufactured and recycled chemical solvents used in stripping paint. The plant closed in 1984.

The EPA’s Terry Connelly, who has overseen the cleanup of the site when it began in 1993, said Wednesday that a required report documenting the last several years shows that contamination is contained on the former Union Chemical property on Route 17.

Monitoring wells on adjacent properties have not revealed any trace of the contaminants, he said.

“The conclusion is the remedy is working as designed,” Connelly said, though some modifications have been made. “The remedy remains protective.”

Buildings on the property were decontaminated and removed by 1994, Connelly said.

In early 1996, cleanup efforts focused on soils and groundwater. Early on, pumping groundwater from the site resulted in 50 to 100 pounds of contaminants being removed per month, but after a few months, the levels dropped to 3 to 4 pounds, he said.

In 1998, after pumping for more than two years, the EPA approved a more aggressive approach, hoping to speed up the estimated 15-30 years it would take to bring the groundwater into compliance. A permaganate solution – also used in wastewater treatment plants – was injected into the ground.

“What we found was it was very effective for a particular group of chemicals,” Connelly said, but less effective for another group.

Last year, sodium lactate, a milklike compound, and molasses were applied to the soils in the hope that the substances would provide a food source for microorganisms. The microorganisms, in turn, consume oxygen dissolved in the groundwater, which renders the water anaerobic, Connelly explained, which helps the chemicals degrade.

This past summer, the sodium lactate and molasses treatment continued, but the EPA is not ready to agree that it is working, he said.

A consultant hired by the parties responsible for the cleanup – those connected to the plant’s operation – is administering the remedies, Connelly said.

Beginning Oct. 21, EPA officials will gather samples from the soils to see whether the new treatment is working, or whether the chemicals are degrading at the same rate that would be expected with no treatment.

The top 10-15 feet of the soils are now clean. The goal of the cleanup is to have the groundwater meet federal and state drinking water standards, Connelly said.

“We’re much more realistically closer to meeting that standard,” he said.