Understanding the Lower Hackensack River – Implications of Its Recent Listing as a Superfund Site

The Lower Hackensack River is a 23-mile stretch of the Hackensack River flowing through Bergen and Hudson Counties in New Jersey and extending from Oradell Dam in the north to its confluence with Newark Bay.

On March 17, 2022, USEPA announced it was proposing to add the Lower Hackensack River to the National Priorities List (NPL) to address potential risks to human health and the environment associated with contaminants in sediments, and it was officially listed on September 7, 2022. In October 2023, USEPA identified the Turning Basin as Operable Unit 2 (OU-2); the entire site continues as OU-1. The designation of operable units will afford USEPA the flexibility to address specific areas more effectively.

“The Lower Hackensack River, associated wetlands, and surrounding area have been a center of industrial activity for more than 200 years. Decades of sewerage and industrial discharges into the river and its tributaries have contaminated river sediment.”

– USEPA Website

Lower Hackensack River

The Hackensack River is part of the New York/New Jersey Harbor Estuary. Key factors that are important to the conceptualization of the sources, fate, and transport of constituents of concern (COCs) within the Lower Hackensack River include:

  • Tidal connection to Newark Bay (NPL Site), which is similarly connected to the Lower Passaic River (NPL Site), Arthur Kill, and Kill van Kull; tidal connectivity results in routine exchanges of sediments and surface water with adjacent waterways. 
  • Berry’s Creek (NPL Site) and 16 other tributaries discharge into the Lower Hackensack River.
  • Nine NPL sites are located within a 1-mile radius of the Lower Hackensack River.
  • Numerous publicly owned treatment works discharge to the Lower Hackensack river, contributing a significant portion of its freshwater input.
  • Intense development in its watershed has resulted in decades of industrial and urban discharges to the river, including stormwater and sanitary inputs.

These factors result in a dynamic environment for the Lower Hackensack River, with historical and current inputs of COCs and periodic exchanges with other regional waterways, some of which are also listed on the NPL.

EHS Support's Commitment

With years of experience at sediment megasites and over five decades of combined consulting experience in the New York/New Jersey Harbor Estuary, EHS Support made a significant commitment in 2022 to better understand the Lower Hackensack River, to compile and analyze publicly available data, and to COCs throughout the river and regionally. This proactive approach provides our clients with an unprecedented level of understanding years before remedial investigations start , which will help to inform future strategies should their involvement in the Lower Hackensack River Superfund Site be needed.

Planning for the Future

EHS Support has sponsored 12 interns over the past two summers to work alongside our scientists, risk assessors, engineers, and statisticians to gain first-hand, real-world experience in understanding the physical, chemical, and ecological complexities of the Lower Hackensack River. Six of our past interns have joined our team as full-time scientists to start their environmental careers. 

Seven interns were selected for the 2024 internship program out of over 260 applicants.

Understanding Nature & Extent of Constituents of Concern

Analyzing the extensive sediment dataset from our geospatial database, we can develop a better understanding of COC nature and extent. This understanding helps us develop strategies for how best to interpret source identification and inform possible investigation and remedial strategies. The database affords us the ability to answer the following questions:

Future Implications & Lessons Learned

EHS Support continues to develop its Conceptual Site Model for the Lower Hackensack River. Based on our research and the data analyzed, we have learned:

  • The Lower Hackensack River has received decades of industrial and urban discharges, including stormwater and sanitary inputs.
  • The Lower Hackensack River also receives sediments (and potentially COCs) from Berry’s Creek and Newark Bay, as well as the greater watershed above Oradell Dam and other tributaries.
  • Potential COCs for the Lower Hackensack River include polychlorinated biphenyls (PCBs), polyaromatic hydrocarbons (PAHs), Dioxins/Furans, arsenic, chromium, lead, and mercury.
  • COC concentrations are greater than background and remedial goals established for other NY/NJ Harbor Estuary Sites.
  • While exhibiting similar urban characteristics to other neighboring waterways, the river has unique elements to its conceptual model including sources of freshwater flows.
  • Data analysis has shown patterns and trends in COC concentrations that could be used to identify areas for potential Early Action.
  • Data suggests that Reaches could be defined by COCs and potential source identifications could be achievable.

Stakeholder Engagement – EHS Support’s Sediment Workshops

EHS Support has been actively involved in stakeholder engagement through a series of Sediment and PRP Summits to foster open discussions on early actions/source removals to:

  • Achieve early risk reduction
  • Improve system understanding
  • Return natural resources back to the community as early as possible
We will be continuing this discussion during a one-day Sediment Workshop on May 8, 2024, in New York, NY.

Our Project Experience