Newark Bay Study - Passaic River Public Digital Library

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westerly section of the Kill van Kull, where concentrations significantly exceed the ER-M value.
This is also true in the deeper sediments (between 0.5 and 4 ft) of the Kill van Kull, which also
suggests the presence of other potential sources of lead in the vicinity of the Kill van Kull. In
Newark Bay proper, deeper sediments have generally lower levels of lead, with the exception of
locations closer to the mouth of the Passaic River, where deeper sediments have significantly higher
levels that are well in excess of the ER-M. Data reported by Suszkowski (1978) suggest that surficial
sediment lead concentrations were somewhat higher at that time, with a number of surface sediment
concentrations exceeding the ER-M. Whether the surface lead data of Figure 1-22 should be
considered as being indicative of conditions having improved since 1976, or simply an artifact of use
of different sampling or analytical methods, requires further review. (This same point applies to the
comparisons to be made with other 1976 sediment metal results as well.)
In general, the levels of nickel in surface sediments are between the ER-M (51,600 ng/g) and
the ER-L (20,900 ng/g) values (Figure 1-23). There are, however, exceptions – the ER-M is
exceeded in surface sediments at locations close to the mouth of the Passaic River, but also
downstream between RM4 and RM6, as well as occasionally in the Kill van Kull. These results also
suggest the presence of other potential sources of nickel in the vicinity of Kills. In deeper
sediments, nickel levels tend to increase relative to surface levels where measured throughout the
domain. This is particularly noticeable in the first two miles and in the lower section of Newark Bay,
in the 2 to 4 ft sediment layer. The surficial sediment nickel concentrations reported by Suszkowski
were comparable to the results of Figure 1-23, with most values in the range of 10,000 to 100,000
ng/g and a number of sample results exceeding the ER-M for nickel.
Arsenic levels in surface sediments are well below the ER-M value (70,000 ng/g), and hover
above the ER-L guideline of 8200 ng/g (Figure 1-24). It is however noteworthy, that despite the
limited number of measurements, arsenic concentrations seem to increase with depth, particularly at
locations close to the mouth of the Passaic River, where the 7 to 13 ft layer shows one instance
where the arsenic level is close to the ER-M guideline value. The 1976 surface sediment arsenic
levels seem to have been comparable to the more recent data of Figure 1-24.
Cadmium concentrations in surface sediments are generally substantially lower than the ER-
M (9600 ng/g) but still higher than the ER-L (1200 ng/g) (Figure 1-25). However, in deeper
sediments closer to the mouth of the Passaic River, but also in certain areas of the Kill van Kull (at
RM6.8, between 0.5 and 2 ft), cadmium levels are in excess of the ER-M. The 1976 surficial Cd
concentrations reported by Suszkowski (1978) indicated numerous values in excess of the ER-M
with a maximum concentration of 31,000 ng/g. Samples from a limited number of borings, which
had concentrations in the range of 600 – 3400 ng/g, had somewhat lower levels than was indicated
by the surface samples.
In spite of the trends of metal contamination in Newark Bay sediments described above, the
deposition, resuspension and redeposition features of the Bay have likely altered historic spatial