The Challenge

Immediately adjacent to the Passaic River in a congested urban area of Newark sits a former Manufactured Coal Gas Plant site owned by the PSE&G Company. Over the years, the by-products of the coal gasification process (including coal and tar) had leached into the ground and contaminated both the water and soil. This concerned residents because the area was to be re-developed as a public green-space.

The Solution

The Conti Group performed state-of-the-art remediation techniques to remove the contaminated soil from the site. The team constructed three reinforced steel cofferdams, which when combined with a dewatering system of shallow and deep wells, Piezometers reaching 100 feet, and five tiers of internal bracing, allowed excavation to depths of 60 feet right next to the river. Conti also protected twin active gas mains, 30-inch diameter, using 344 cubic yards of jet grout. Once excavated, the contaminated soil was blended with clean soil and cement kiln dust, and then transported to Thermal Desorption facilities where it met strict acceptance criteria.

Conti worked hard to maintain safe on-site practices, kept to a strict schedule, and successfully delivered the project. This major riverfront site was re-developed for the City of Newark.

Scope of Work