T1 PM Contaminant Cycling Assessment and Prevention in the NY/NJ Harbor (Part 2)
Tuesday, 15 November 2005: 1:50 PM - 5:30 PM in Ballroom 1

(MIL-1117-857771) Mass balance model evaluations of PCB and dioxin accumulation in New York-New Jersey Harbor.

Miller, R¹, Wands, J¹, Farley, K^{1, 2}, ¹ HydroQual, Inc., Mahwah, NJ, USA² Manhattan College, Riverdale, NY, USA

ABSTRACT- The accumulation of PCBs and dioxins in New York-New Jersey Harbor is a pressing concern due to fish consumption advisories and restrictions on dredged material disposal. A large field data collection program and mass balance modeling study are being performed under the Contaminant Assessment Reduction Project (CARP) to evaluate problems of harbor contamination. As part of this effort, we are conducting mass balance modeling studies to explore the roles of estuarine circulation and sediment transport on the fate and transport of PCBs and dioxins in the harbor region. Model calculations show that tidal and density-driven circulation patterns play a key role in trapping significant quantities of PCBs and dioxins in harbor sediment, in spreading contaminants over large areas of the harbor, and in maintaining a close link between contamination in sediments, overlying water, and fish. This results in long response times for PCBs and dioxins to changes in external loadings of contaminants. In addition, certain areas of the harbor where tidal effects are less important show the persistence of contaminant hot spots over longer periods of time. These findings underscores the importance of legacy contamination in determining present concentrations of PCBs and dioxins in harbor sediment and biota.

Key words: PCBs, dioxin, sediment contamination, model