MONITORING CRUISE 



AT THE WESTERN LONG ISLAND SOUND DISPOSAL SITE 



JULY 1988 



1.0 INTRODUCTION 



The Western Long Island Sound Disposal Site (WLIS) is 

 located 2.5 nautical miles north of Lloyd Point, NY, between the 

 Stamford and Eatons Neck historic disposal grounds. Since disposal 

 first began at the site in March 1982, varying quantities of dredged 

 material have been deposited annually. As a result, three dredged 

 material disposal mounds ("A", "B" , and "C") currently exist at the 

 site (Figure 1-1) . 



The disposal buoy was located at the "B" mound at 

 coordinates 40 59.340 N and 73 29.346 W during the 1987-88 disposal 

 season (1 September 1987 to 1 June 1988) , identical to its position 

 during the 1986-87 season. Tabulation of scow logs indicated that 

 approximately 52,842 m 3 (69,074 yds 3 ) of dredged material were 

 deposited at or near the buoy between 17 November 1987 (when the 

 last bathymetric survey occurred at the site) and the end of the 

 1987-88 disposal season on 1 June 1988. 



From 19 to 22 July 1988, field operations were conducted 

 at WLIS to provide information on the fate of recently-disposed 

 dredged material and assess the environmental effects of past and 

 recent disposal operations. The field operations consisted of a 

 precision bathymetry survey, REMOTS® sediment-profile photography, 

 measurements of near-bottom and near-surface dissolved oxygen 

 concentrations, and determination of the vertical profiles of 

 temperature and salinity at selected stations. The objectives of 

 the 1988 monitoring cruise at WLIS were to: 



■ delineate the extent and topography of the dredged 

 material deposited at the site since the November 1987 

 survey , and 



■ characterize dissolved oxygen depth gradients as well as 

 assess near-bottom dissolved oxygen concentrations 

 relative to REMOTS® benthic analyses at and near the 

 disposal site. 



2 . METHODS 



2.1 Bathymetry and Navigation 



The precision navigation required for all field operations 

 was provided by the SAIC Integrated Navigation and Data Acquisition 

 System (INDAS) . This system uses a Hewlett-Packard 9920 series 

 computer to collect position, depth, and time data for subsequent 



