shells overlaying a layer of what appeared to be anoxic dredged 
material extending below the penetration depth of the REMOTS® 
prism. The bottom in this area sloped quite dramatically to the 
southwest (Figure 3-2). Beginning at a depth of approximately 25 
meters in the northeast, the depth increased to over 70 meters to 
the southwest (beyond the edge of the Master survey). These data, 
combined with a more detailed analysis of the REMOTS® survey, 
showed that this area would be unsuitable for use as a disposal 
point due to the apparent high kinetic energy of this location and 
the fact that it was located outside the disposal site boundary. 
A new disposal point was located in the central and eastern section 
of the disposal site (designated as NL-85) and baseline conditions 
prior to disposal operations were surveyed (NLON-85 survey area). 
The depth in this area (Figure 3-3) varied from approximately 16 
meters over the NL-III disposal mound in the north central portion 
of the area down to greater than 23 meters in the southern portion 
of the site. Three disposal mounds (NL-I, NL-II, and NL-IITI) 
represented the most distinctive topographic feature of this area, 
while the ambient bottom tended to slope very gently to the south. 
The buoy was positioned so that the addition of a significant 
quantity of dredged material would tend to consolidate the three 
existing disposal mounds. 
The results of the post-disposal bathymetric survey 
around the NL-85 disposal point (Figure 3-4) revealed the 
establishment of a mound of dredged material centered approximately 
100m southeast of the disposal buoy. The height of the mound was 
approximately 2 meters and extended from 250 to 350 meters from the 
center (Figure 3-5). This mound was the result of the disposal of 
approximately 377,500 m° (493,400 yd°) of dredged material, as 
estimated from the scow logs. 
During the July 1986 Master survey, the bathymetric 
features (Figure 3-6) were identical to those seen during the 
August 1985 survey of the same area except for the addition of the 
NL-85 mound to the four older mounds (NL-RELIC, NL-I, NL-II, and 
NL-III). In order to determine small changes in bathymetry in the 
area of the five disposal mounds, another survey was conducted 
(NLON-86 survey in Figure 2-1) at a 25 m lane spacing. The 
contoured depth chart of this area (Figure 3-7) gives greater 
detail as to minimum depths of each mound as well as their areal 
extent. The NL-RELIC mound was the shallowest at a depth of 
approximately 13.5 meters. Mounds "NL-I", "NL-II", and "NL-III" 
had minimum depths of 15.5, 15.5, and 14.5 meters, respectively. 
In order to compare the results of the July 1986 survey 
with those obtained in November 1985 (Figure 3-3) and January 1986 
(Figure 3-4), the raw bathymetric data were regridded to match the 
survey designated as "NLON-85" in Figure 2-1. This encompassed the 
area of the most recent disposal operations. All the bathymetric 
features seen in the July 1986 survey (Figure 3-8) appeared 
identical to those seen in January, except for the increase in 
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