Cleanup continues at university's former chemical disposal site near airport

Cleanup efforts continue at the university's former Chemical Disposal Site (CDS) north of Tompkins County Airport. This fall, an existing groundwater collection trench is being upgraded as part of a work plan submitted to the New York State Department of Environmental Conservation (DEC) earlier this year. And a final plan for all cleanup activities will be developed following a public-comment period in early 1999.

Chemicals being cleaned up are mostly organic chemicals and solvents that were disposed of at the site during the 1960s and 1970s using methods approved at that time. According to university and DEC records, the site does not pose health risks.

Elizabeth Cameron, project manager at Cornell's Office of Environmental Compliance, said cleanup activities at the site over the last six years include three barriers to keep chemicals from leaving the area.

First, an underground clay barrier wall was placed around the waste, and pumps were placed inside the waste area to remove contaminated water from within the former waste-disposal site. Second, a synthetic cover was placed over the top of the disposal area to isolate the waste and keep rainwater from coming in contact with the waste. And, third, a recovery trench was placed on airport property to capture contaminated groundwater that had migrated from the CDS.

Testing that Cornell performs every three months near the trench shows that contaminated groundwater may be flowing beneath it, thus the recovery trench system is being improved, Cameron explained. She said Cornell is installing more wells that extend deeper than the recovery trench to capture contaminated groundwater. Contaminated groundwater intercepted by the deeper wells will be combined with water from the trench and treated at a special treatment plant before being discharged.

Since 1992, when DEC approved the university's cleanup plan, leachate from the waste-disposal area and contaminated groundwater have been pumped to the treatment plant next to the CDS. The water is passed through carbon filters to remove organic chemicals, and treated water is discharged to a stream.

"Discharged water is tested at least monthly to make sure that the treatment process is removing contaminants and is meeting all of DEC's discharge requirements," Cameron said. Cornell also tests groundwater and surface water around the former disposal site every three months to evaluate the effectiveness of the cleanup, she added.

In 1997, the plant -- which operates year round -- treated about 15.5-million gallons of water pumped from the waste-disposal area and recovery trench. About five pounds of organic chemicals, mainly organic solvents, were removed, Cameron reported.

The stream that receives discharge from the treatment plant is sampled three times a year to monitor its health. Organisms are collected from the bottom of the stream bed at several locations downstream of the treatment plant. Sampling results to date show there has been no environmental degradation of the stream from Cornell's CDS or its former radiation disposal site nearby.

The upgraded groundwater collection trench is being designed by McLaren/Hart Environmental Services East, which is designing the groundwater cleanup of the former low-level Radiation Disposal Site (RDS), also on Snyder Road north of the airport. That site was used to bury low-level radioactive research materials (including animal carcasses and laboratory waste) between 1956 and 1978, in accordance with state and federal regulations in effect at that time.

The first remedial effort at the RDS involved placing an impermeable cover over the waste in 1996. Cornell is evaluating additional cleanup measures for the RDS, Cameron said.

The work plan for upgrading the groundwater collection trench, and other CDS and RDS documents, are available to the public at the Tompkins County Public Library, the Lansing Village Hall and Cornell's Environmental Compliance Office in East Hill Plaza.