The Lower Passaic River is a roughly 17 mile stretch of river from Dundee Dam near Garfield, New Jersey to Newark Bay. The Lower Passaic River (LPR) and Newark Bay (NB) form an estuary subject to both tidal and riverine influence, and where sediments are a combination of cohesive and non-cohesive material.
The U.S. Environmental Protection Agency (EPA), U.S. Army Corps of Engineers, New Jersey Department of Transportation, and New Jersey Department of Environmental Protection partnered to oversee and develop a comprehensive study of the Lower Passaic River Study Area (LPRSA), pursuant to CERCLA (Superfund Law). Moffatt & Nichol managed and carried out the numerical modeling support program associated with the Lower Passaic River Remedial Investigation and Feasibility Study (RI/FS) for the LPRSA Cooperating Parties Group. The modeling scope included the lower 17 miles of the Passaic River as well as Newark Bay with portions of the Hackensack River, Arthur Kill, and Kill van Kull. The program involved developing and applying hydrodynamic, sediment transport, and organic carbon models, supporting contaminant fate and transport under existing conditions, and subsequently using the modeling tools to inform the most cost-effective remediation.
We developed multiple hydrodynamic and sediment data collection campaigns in the course of the program, and our team performed detailed analyses of sediment and contaminant data and model results to understand and describe the extent of contamination of sediments in the LPR. The LPR-NB modeling system was developed with the aid of existing and new field data and resulting conceptual system understanding, and subsequently applied to evaluate future conditions with existing, planned, and proposed remediation scenarios. A Record of Decision finalizing the cleanup plan for sediments of the lower 8 miles was issued by the EPA in 2016. Focused Feasibility Study for the upper 9 miles of the LPR evaluating a range of remediation options is ongoing.