Sediment, Carbon, and Trace Contaminant Contributions to the New Jersey Meadowlands Area from the Hackensack River Basin

 

Timothy P. Wilson, PhD.

Jennifer L. Bonin

 

U.S. Geological Survey

West Trenton, New Jersey

tpwilson@usgs.gov

 

 

 

The health of the Hackensack Meadowlands ecosystem is affected by the sediment, carbon, and contaminants transported from the upland regions of the Hackensack River basin. Understanding the environmental processes that operate within the Meadowlands is, therefore, predicated on a thorough characterization of the chemistry, and mass-loads of contaminants in the Hackensack River basin. Approximately 74 percent of the 113 square mile Hackensack River basin is urbanized, and at least 71 permitted dischargers, including 4 publicly owned watewater-treatment plants, exist in the basin. These inputs combined with other point and non-point sources in the river basin represent the upstream sources of water, sediments, and chemicals to the Hackensack Meadowlands. As part of the Toxics Reduction Workplan for the NY-NJ Harbor, a study was conducted to estimate the loads of suspended sediment, organic carbon, particulate nitrogen, and select trace elements at the head-of-tide of the Hackensack River. Trace organic compounds were measured in the suspended sediment and water, and include polychlorinated biphenyls (PCB), dioxins, furans, polycyclic aromatic hydrocarbons (PAH), pesticides, and metals. Large-volume (>50 liters) samples were collected at the Oradell Reservoir outfall, in Oradell, N.J., which is located several miles upstream from the Hackensack Meadowlands. Estimates of yearly sediment and carbon loads were made using a rating curve produced from U.S.Geological Survey data that were adjusted using the Bradu-Mundlak Estimator procedure. The average yearly flow from the Oradell Reservoir is approximately 15,000 million gallons per year and carries an estimated 400,000 kilograms (kg) of sediment per year. Average contaminant loads are estimated to be 0.05 kg per year for total PCBs, 0.05 kg per year for total PAHs, 0.002 kg  per year for total pesticides, 17 kg per year for total Pb, 0.21 kg per year for total Cd, and 0.038 kg per year for total Hg. These loads, and the chemical “fingerprints” for the PCBs, dioxin/furans, PAHs, and trace metals are pre sented and compared to samples collected from downstream in the estuary and from point-source discharges.