Newark Bay Study - Passaic River Public Digital Library

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an exhaustive data analysis has not as yet been performed. Readily available data have been obtained
and undergone a preliminary analysis, in part to better understand the issues and water quality
problems within Newark Bay and in part to better identify areas where additional data are required.
Efforts will be expended during the project to identify, obtain and utilize additional historical data
sets as well as to utilize data sets being collected as part of the Newark Bay study. As further data
are collected and analyzed and as our understanding of Newark Bay and its interactions with
adjacent waterbodies improves, it may be necessary to modify elements of the work plan in order to
develop the most technologically sound and defensible model of the Newark Bay system. This
analysis is therefore not exhaustive as further data analyses will be conducted as part of the fate and
transport modeling exercise. For example, other transects, such as a longitudinal transect of the
chemical concentrations in the northern portion of Newark Bay and into the Hackensack River
might provide further insight on the distribution of chemicals in the Bay. For this analysis, results
from sediment cores were therefore plotted on multi-panel graphs, each representing the depth
interval at which measurements were taken. The depths for which measurements are available vary
among surveys, and in general do not exceed 14 ft. The lateral distances between stations also vary
considerably along the same river mile. Unless otherwise indicated no distinction was made
between samples obtained within or outside the navigation channel. It is important to note that a
unified river mile (RM) system for both the Lower Passaic River Restoration Project and the
Newark Bay Study will be put in place by the project team. In this analysis, however, the first river
mile system depicted on the spatial plots, based on TSI’s boundaries of the Newark Bay Study Area,
overlaps with the Lower Passaic River Restoration Project river mile system.
In order to conduct a comparative evaluation of the data spatially and on a matrix basis (i.e.,
water column, pore water, sediment and fish tissue), multi-panel plots, each representing an
environmental matrix, were generated for each chemical whenever concurrent measurements were
available. Note that such concurrent measurements were rare. For example in the case of arsenic,
there are only two water column and five surface sediment measurements in the Port Newark
Channel between 1993 and 1999, whereas in the Elizabeth Channel, no water column or fish tissue
measurements are reported. When available, the Effects Range - Low (ER-L) and Effects Range -
Median (ER-M) concentrations for sediments (Long et al., 1995) are provided for comparison
purposes. These concentrations are intended to define concentration ranges within which adverse
effects are rarely (ER-M). It is also important to note that a more complete analysis of the data
should consider normalizing concentrations of COPCs and COPECs to organic carbon, since this
might help explain some of the spatial and temporal variations of chemicals in the sediments. This
analysis will be conducted as part of the data analysis task of the fate and transport modeling.
The potential COPCs and COPECs that are presented are PCBs, PAHs, dioxins, DDT and
metals, all in dry weight units. As indicated below, there are large gaps in the type (i.e., only few