The SAIC Integrated Navigation and Data Acquisition System (INDAS) provided the 

 precision navigation required for all bathymetric and REMOTS® field operations. Shore 

 stations for CSDS surveys were at known benchmarks at Cornfield Point (41° 15.79' N, 

 72°23.04' W) and Lynde Point Light (41°16.29' N, 72°20.59' W) in Old Saybrook, CT. 

 An Odom DF3200 Echotrac® Survey Recorder with a narrow-beam 208 kHz transducer 

 recorded depth to a resolution of 3.0 cm (0.1 feet) as described in DAMOS Contribution 

 No. 48 (SAIC 1985). Contribution No. 60 (SAIC 1989) contains a detailed description of 

 INDAS and its operation as well as the bathymetric analysis technique. 



2.2 Current and Suspended Sediment Measurements 



During the 1991 surveys, two moorings were deployed at CSDS (Bohlen et al. 1992). 

 One mooring (BTM) was equipped with a single InterOcean Systems, Inc. S4 current meter, 

 two 10 cm pathlength red-light transmissometers, and a single red-light optical backscattering 

 sensor (D&A OBS-1 Sensor) located approximately one meter above the bottom. The second 

 mooring (MWM) was equipped with a single S4 current meter positioned 11m below the sea 

 surface. These two current meters measured the direction and magnitude of the currents. 

 The transmissometers and optical backscatter sensors attached to the near-bottom current 

 meter (BTM) measured suspended sediment concentrations. All the moored instruments 

 burst sampled 4 times an hour at a rate of twice per second for one minute. 



On June 23, 1991, the A disposal buoy was deployed at 41° 12.69' N, 72°21.54' W. 

 The near-bottom mooring (BTM- A) was positioned approximately 500 m northwest of this 

 buoy on July 18. The water depth at BTM-A was approximately 53 m, and the instrument 

 package was located one meter above the seafloor. A mid- water mooring (MWM), with a 

 S4 current meter 11m below the surface, was deployed southwest of BTM-A on August 1 

 (Table 2-1, Figure 2-1). Buoy A was moved north to its final location (41° 12.75' N, 

 72 °2 1.10' W) on August 8, prior to the start of disposal to further separate the disposal 

 location from a previously used location to the south (Table 2-1, Figure 2-1). On August 13, 

 the optical backscatter sensor and transmissometer package (DAISY) was added to the bottom 

 mooring (BTM-A). After the Connecticut River bars dredging was completed, the disposal 

 buoy was relocated on October 18 to location B (Table 2-1, Figure 2-1). The near-bottom 

 current meter mooring (BTM-B) was moved approximately 500 m to the west of B on 

 October 21. The water depth at BTM-B was approximately 53 m. Again, the instrument 

 package was housed one meter above the bottom. The DAISY instrumentation was removed 

 from BTM-B on November 27th. A mid-water mooring, with a current meter positioned 

 11m below the water surface, remained at the same location for the duration of the study. 

 The last data retrieval for BTM-B and MWM was December 12, 1991. The moorings were 

 removed from the water on January 9, 1992. 



Synthesis of Monitoring Surveys at the Cornfield Shoals Disposal Site, July 1991 to May 1992 



