Event-Based Variability in Particulate Dioxin/Furan Concentrations
in the Surface Waters of the Passaic River-Newark Bay Complex
Joel A. Pecchioli
Division of Science, Research and Technology, NJ Department of Environmental Protection
P.O. Box 409, Trenton, NJ 08625; 609-633-2200; joel.pecchioli@dep.state.nj.us
Researchers involved with the New Jersey Toxics Reduction Workplan for NY-NJ Harbor collected ambient water samples at eleven stations in the Passaic River-Newark Bay Complex. Large-volume water samples were collected during ebb tides using a Trace Organics Platform Sampler (TOPS), which used a series of glass fiber filters to collect organic contaminants associated with suspended sediments (SS) and particulate organic carbon (POC). The TOPS samples were analyzed for dioxins/furans (PCDD/Fs) using USEPA Method 1613B. Synoptic sampling activities were conducted during two dry weather/low Passaic River flow and two wet weather/high Passaic River flow events. Suspended sediment and POC levels did not vary consistently with river flow conditions. There was little correlation between SS and POC levels at 8 of the 11 sampling stations, with a moderate positive correlation at the lower Hackensack River (r = 0.71) and head-of-tide (r = 0.65) stations, and a strong negative correlation (r = -0.96) at the lower Newark Bay station. Total PCDD/F, Total PCDD/F-OCDD, 2,3,7,8-TCDD, and Total TEQ SS- and POC-normalized concentrations did not vary consistently with hydrologic conditions and were not correlated with SS and POC levels. SS-normalized 2,3,7,8-TCDD and Total PCDD/F-OCDD concentrations at a given sampling station were observed to vary by factors of 1.4 to 54 over the four sampling events. Both SS- and POC-normalized concentrations were reduced during a December 2000 wet weather/high river flow event at most of the sampling stations, suggesting that the concentrations of these contaminants can be diluted by the addition of cleaner sediments to the water column during some such events. During an October 2001 dry weather/low flow event, POC- (but not SS-) normalized concentrations were elevated in the Passaic River, upper Newark Bay, and lower/mid Hackensack River (290-2,000 ng/g POC; < 180 ng/g POC during the other three events), indicating a significant source of PCDD/Fs is present in the lower Passaic River. Little variability was observed in the dioxin/furan congener distribution patterns at each site during the four sampling events. The NJTRWP data suggest that the transport and fate of PCDD/Fs associated with suspended particulate matter in the Passaic River-Newark Bay Complex can vary in a complex manner in response to hydrologic conditions. Therefore, this limits the usefulness of mean concentrations to describe contaminant distributions in these water bodies.
Funding for this project was provided by the Port Authority of New York-New Jersey via the New Jersey Department of Transportation Office of Maritime Resources.