SI Group begins cleaning up spill site

PHOTOGRAPHER: Kathleen Moore

Share on Facebook

Save

The torrential downpours of late haven’t put a damper on cleanup of ground pollutants on Congress Street.

SI Group, formerly known as Schenectady International, is back at its old chemical manufacturing plant to clean the soil at 1302 Congress St.

The company is spending $4.3 million on the one-year job, which will restore the site to the point where it could be used by other businesses. Work began the day before the region was socked with rain from a second tropical storm.

“There’ve been no delays,” said SI Group spokeswoman Juliana Lam.

That’s partly because the company did not have to immediately start digging in the wet soil. Workers are setting up equipment and running electrical wires to prepare the site for cleanup, Lam said. The project is scheduled to be complete next year.

The company began cleaning the grounds as it closed down the plant in 1997. Groundwater was pumped and treated before leaving the site.

Then SI took down all of its buildings in 2004, laying bare the entire property for cleaning. Machines will heat the soil to turn the pollutants into gas, and then suck the gases out of the ground for treatment.

Once most of the pollutants are removed, the soil will be heated more gently to encourage the remaining contamination to break down naturally.

On the western side of the site, the job will be more complicated. Workers found that contaminated surface water was seeping down the hill.

SI Group built a fence to keep the public off the hill, but found that the pollution is buried too deeply for excavation and can’t be removed by heating. The groundwater will be removed instead while the pollutants break down naturally.

When the cleanup is complete, water will no longer need to be collected and treated.

The 7-acre site was contaminated when workers spilled chemicals that were mainly used to create insulated coatings. Spills ranged from a few gallons to a few hundred gallons, and over time, that added up. The plant was used for nearly 100 years.

Ground pollution investigations didn’t start until the 1980s, and quickly found solvents and other chemicals. SI Group began installing groundwater monitoring wells in 1984.

When SI left the site, it was placed on the state Superfund list as a class 2 inactive hazardous waste site. A class 2 site is a “significant threat to public health or the environment,” and the state Department of Environmental Conservation requires it to be cleaned up.