4.0 DISCUSSION 
The NLON Master bathymetric survey was conducted in 1985 
and 1986 along with REMOTS® sediment profile surveys extending 
beyond the disposal site boundaries in 1985 and at each of the five 
disposal mounds in 1986. The purpose of these surveys was to 
detect any evidence of significant dispersion of dredged material 
and subsequent environmental impacts related to disposal. 
Comparison of the 1985 and 1986 Master bathymetric surveys did not 
reveal any significant changes in bottom topography, except where 
the NL-85 mound was established (see below for further discussion) . 
The minimum depths at the peaks of the NL-I, NL-II, NL-III, and NL- 
RELIC mounds remained essentially unchanged. 
Results of the analysis of REMOTS® photographs obtained 
during the July 1985 field investigation at the New London Disposal 
Site suggested that dredged material may have been present beyond 
the margins of the southwestern quadrant of the disposal site, 
apparently due to the stressed conditions there. This area was 
being considered as a new disposal location. Due to the coarse 
nature of the sediments, shallow camera penetration depths 
prevented the detection of buried redox layers at several stations. 
The side scan sonar survey performed in August 1985 indicated an 
area of high acoustic reflectance outside the southwest border, 
also suggesting the presence of dredged material. However, high 
reflectance is also characteristic of coarse-grained sediment. The 
high concentrations of metals and oil and grease in the sediment 
at stations C-13 and E-14 in the July 1985 survey contrasted 
sharply with the lower concentrations of the other three stations 
further south and west, also indicating the possible presence of 
dredged material. 
REMOTS® and precision bathymetric surveys were conducted 
in the southwest quadrant extending outside the disposal site 
boundaries again in August 1985. Analysis of these REMOTS® 
photographs did not detect the presence of dredged material. 
Additional stations were surveyed in the southwest area in July 
1986 to further investigate the possible presence of dredged 
material. Close examination of the REMOTS® photographs from the 
24 stations in this southwest reconnaissance grid, which extended 
the range of the area previously surveyed in July 1985, revealed 
that no apparent dredged material was present. This area 
corresponds to a bathymetric gradient increasing from northeast to 
the southwest; the photographs suggested that this is a 
high-kinetic area with surface shell lag layers. There was no 
evidence of dredged material dispersing beyond the perimeter mapped 
in the July 1985 survey. No other areas outside the disposal site 
boundaries were suspected of containing dredged material. 
The steeply sloping bottom topography and the apparent 
high kinetic energy of the southwest quadrant made it unacceptable 
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