NORWICH – On Thursday, the New York State Department of Environmental Conservation will hear public comments on a proposed $11.2 million remedial plan for a property located on Birdsall Street in the City of Norwich.

The former NYSEG Manufactured Gas Plant (MGP) site, located at 24 Birdsall St., produced coal gas and what’s known as carburetted water gas until 1953. The production of the gases included a cooling process, which utilized ground water as a bottom seal for cooling and pressure purposes, which significantly increased the potential for byproducts to be introduced into the ground water and subsurface area.

While remedial action was taken at the site several times, the DEC and the Department of Health are proposing further action be taken to address contamination.

According to representative Diane Carlton, the DEC has recommended a process known as “in-situ” solidification of the on-site sub-surface soils, as well as two off-site properties. It’s also calling for the collection and removal of mobile coal tar from beneath off-site areas, further in-situ chemical oxidation treatment of off-site contaminated soils, enhanced bioremediation of groundwater and an environmental easement.

In-situ solidification prevents groundwater from traveling through the contaminated soil. The process would require the top six feet – approximately 1,800 tons – of soil to be removed from the site and disposed of before a cement or clay like material was brought in. The clay would be mixed with the existing soil, using a large auger.