NORWICH – A procedure to keep coal tar from contaminating groundwater at the site of an old gas manufacturing plant in the city is expected to begin in April, an official with New York State Electric and Gas confirmed Monday.

NYSEG, a subsidiary of Energy East, was ordered by the state Department of Environmental Conservation in March 2008 to clean up the site, located next to the P&C plaza behind Birdsall and Front streets. A second, smaller section near the railroad tracks on Front Street is also being decontaminated.

The larger of the two polluted spots was formerly home to the NYSEG Manufactured Gas Plant, which produced coal and carburetted water gas until 1953, according to Evening Sun records.

Public meetings will be held before the actual remediation work at both sites begins, said NYSEG spokesman James Salmon.

Once completed, city officials hope the property can be developed for commercial use.

“This is good news for the city, to have an over three-acre area clean and ready for development,” said Mayor Joseph P. Maiurano. “We hope it will be ready by 2011. We’ll have to go back to our comprehensive plan and consult our planning commission, and find out what we can best utilize that area for.”