Project Experience

Confidential Client – Residential Redevelopment, Soil Remediation, Containment Cell, Groundwater Modeling for a NJ Brownfield Development

Modeling a key activity needed to further redevelopment plans

Cornerstone staff are providing groundwater investigation and modeling services for a component of one of the largest Brownfields redevelopment projects in New Jersey. Redevelopment plans call for the excavation, relocation, and containment of contaminated soils in on-site containment cells. The cells will be surrounded with a sheet pile wall and capped with a low-permeability cover that will become a green-way (park) within the redevelopment.

Containment cell performance criteria stipulate that intra-gradient conditions must be maintained around the perimeter. This means that groundwater elevations must be higher outside of the sheet pile wall and within the containment cell.

The work conducted by Cornerstone staff included the delineation of contaminant plumes, the identification of groundwater levels and flow direction, and the prediction (through modeling) of the impacts of the various containment cells on flow. A sensitivity analysis of the various capping and barrier wall options was conducted to optimize the design. The work was complicated by the identification of locally depressed water levels associated with subsurface utilities and other structures.

Cornerstone’s hydrogeologists worked closely with project engineers to design various methods of isolating these structures while still maintaining their function and meeting the intra-gradient project requirement.

Key Project Activities

  • Investigation of deep overburden groundwater plume
  • Groundwater modeling of soil containment area
  • Design of contingent groundwater pumping system
  • Redevelopment strategy