Sevenson Environmental Services of Niagara Falls, N.Y., has completed a lead remediation project to excavate and remove lead and arsenic contaminated soil from the yards of houses and commercial properties in the Newhall Street neighborhood in Hamden, Conn. Sevenson excavated to a depth of four feet, removing over 8,700 truckloads (131,700 cubic yards) of toxic fill, backfilled with clean soil, and restored features disrupted during excavation.

Contaminated fill had been placed in the then low-lying area beginning in the 19th century and continuing into the mid-20th century. The fill material included municipal and industrial wastes containing heavy metals, primarily lead and arsenic, and PAHs, a semi-volatile organic compound often associated with wood and coal ash.


The project spanned a 15-block area, covering about 250 residential properties, the largest project of its kind ever undertaken in Connecticut. “This was a success in every way possible,” said Ray Frigon of the Remediation Division of the Connecticut Department of Energy and Environmental Protection. “Sevenson’s team conducted this project with an incredibly high regard for safety of site workers and the public. The number of safe worker hours achieved on this project was particularly impressive, especially in light of the project setting – in the middle of an active residential community.”

The cleanup began in the late summer 2010, with 80 workers and was completed ahead of schedule and well under the anticipated budget.

“This project is representative of the cleanup work Sevenson has done in residential neighborhoods dating as far back as work in the Love Canal neighborhood of Niagara Falls in the 1980s,” said Sevenson Environmental CEO Michael E. Elia. “The extensive and broad experience of our management and crews working in neighborhoods with residents present was a key reason for the success of this project.”
Work also focused on residents’ yards, patios, driveways, sidewalks, and landscaping, replacing 80 structures, planting 4,700 shrubs, plants and trees, installing 210,700 square feet (almost four football fields) of driveways and parking areas, and 20,350 lineal feet (3.8 miles) of sidewalks.