SUFFERN – Orange and Rockland Utilities has begun to remediate the site of a former manufactured gas plant that has been closed for some 80 years on Pat Malone Drive in the Village of Suffern.
The $11-million to $13-million project is expected to take seven to nine months to complete.
Manufactured gas plants operated before natural gas was used for energy production, noted O&R spokesman Michael Donovan. They operated from the early 1800s until the mid-1900s to produce gas from coal for lighting, cooking and heating and were replaced with natural gas after World War II.
The byproduct that will be removed consists of coal-tar, a material similar to driveway sealer.
The Suffern facility, which was operated by a predecessor company to O&R, will be cleaned up through the removal of subsurface MGP holder and the gas oil house structures; evacuation of some 20,000 cubic yards of coal-tar contaminated soil; with 17,000 cubic yards of contaminated soil deeper than 15 feet below the surface being entombed with cement.
Most of the site excavation work will be performed under two large tent-like fabric structures with carbon-filter, air-handling systems that will be moved around the property as work is progressed.
As part of the project, a groundwater monitoring plan has been established to ensure adequate notification to the appropriate agencies in the event that a migration of site-related MGP impacts is detected in the groundwater. If that occurs, an active response plan is in place and would be initiated. Sentinel wells have been in place monitoring the groundwater between the site and the Suffern village water supply wells since 1999. During that time, no impacts to the water supply wells have been found.
