ecosystem recovery at the NL-85 mound, the low species richness in 
the ampeliscid assemblage is well within the expected sequence of 
recolonization events. 
Visual and photo documentation determined that the 
conditions existing at the New London Disposal Site at the time of 
the diver surveys were typical for this site in the post-disposal 
phase. Areas containing dredged material consisted of compact 
cohesive sediments and all areas were densely colonized by 
amphipods. The thick mats of amphipod tubes reduced boundary layer 
flow velocities, thereby reducing erosion and often creating 
depositional environments. Surface features on and off of dredged 
material, except for crustacean "grotto" structures, made the two 
areas virtually indistinguishable. 
The megafaunal assemblage observed was typical for this 
area at the time of the survey and all species observed exhibited 
typical behavior patterns. Bare patches in the amphipod tube 
carpet and shallow excavations were indications of active foraging 
behavior by the local fish and crustacean populations. Lobster 
burrows in the sediment and under debris were common in all 
locations surveyed. A portion of these burrows in each area were 
occupied by lobsters. Sediment burrows were often excavated into 
areas of slight topographic rise, allowing a more vertical burrow 
entrance. 
The recolonization of the NL-85 disposal mound, as well 
as the other mounds, did not appear to be drastically hampered by 
any chemical stress related to the presence of the dredged 
material, despite the fact that concentrations of zinc, chromiun, 
copper, and oil and grease in sediments at the disposal mounds were 
significantly elevated over those found in Reference station 
sediments (though still low relative to ranges of concentrations 
found throughout Long Island Sound). Because chemical 
concentrations were not found to be consistently higher or lower 
in the 0-2 cm sediment layer when compared to the 2-10 cm layer, 
neither shallow-feeding or deep-burrowing organisms should have 
been disproportionately stressed by the contaminants. 
Comparison of results from previous sampling and analyses 
of sediment collected at the NL-I and NL-II mounds and at the 
Reference station indicates that chemical concentrations tended to 
be stable over time. At the Reference station, trace metal 
concentrations in sediment samples from 1982, 1984 (Morton et al., 
1984), and 1986 are all very similar. Lead, cadmium, nickel, and 
mercury showed levels below the analytical detection limits in most 
of these samples. Similar results were found with the trace metal 
concentrations measured at the NL-I and NL-II stations. There did 
not appear to be any systematic temporal or spatial changes in the 
data collected over the four year period at these stations. 
Concentrations of organic compounds also appeared to unchanged over 
the same time period. The total hydrogen and total nitrogen levels 
35 
