established over known benchmarks at Eatons Neck Light and the 

 Norwalk Harbor Power Plant. 



The depth was determined to a resolution of 0.1 feet 

 (3.0 cm) using a Raytheon DE-719 Precision Survey Fathometer with 

 a 2 08 kHz transducer. The fathometer was calibrated with a bar 

 check at fixed depths below the transducer before the survey 

 began. A Raytheon SSD-100 Digitizer was used to transmit the 

 depth values to the SAIC computer system. Survey lanes were run 

 east and west at 25 meter lane spacing over an 800 by 800 meter 

 area centered around the WLIS "A" mound and including the "B" and 

 "C" mounds (Figure 2-1) . This lane spacing provides good 

 resolution for subsequent data analysis and the production of 

 detailed depth contour charts. 



Analysis of the bathymetric data corrects the raw depth 

 values to Mean Low Water by adjusting for ship draft and for 

 tidal changes for the duration of the survey. All data points in 

 terms of depth and position are checked for unreasonable values 

 due to any malfunctions with the peripheral instrumentation 

 (navigation or bathymetry) so that the final contour plots will 

 not contain errors. 



2 . 2 REMOTS® Sediment Profile Photography 



The 198 6 WLIS REMOTS® survey was conducted to map the 

 distribution of dredged material and to evaluate benthic habitat 

 conditions and the process of recolonization in the survey area. 

 In 1985, REMOTS® surveys were conducted at WLIS in August (normal 

 survey area) and in October (a post-hurricane "Gloria" survey 

 limited to the vicinity of the three disposal mounds) . 



REMOTS® images were taken with a Benthos Model 3731 

 Sediment-Profile Camera (Benthos, Inc. North Falmouth, MA) . The 

 REMOTS® camera is designed to obtain in-situ profile images of 

 the top 15-20 cm of sediment. A detailed description of REMOTS® 

 camera operation and image analysis is presented in DAMOS 

 Contribution #60 (SAIC, 1986a) . 



The WLIS 1986 REMOTS® sampling grid consisted of a 63 

 station orthogonal grid (7x9) with stations equally spaced 100 

 meters apart (Figure 2-2) . Three replicate images were obtained 

 at each station. In addition, twenty REMOTS® images were 

 obtained at the WLIS Reference station (40°59.70N, 73°27.75W). 

 Of the three REMOTS® replicate images obtained at each station, 

 one was analyzed for this report and two were archived for 

 possible future analysis. Twenty replicate images from WLIS 

 Reference were analyzed for this report. 



