3.3 REMOTS® Sediment-Profile Survey- 

 Results from 1985 pre and post-Hurricane Gloria surveys 

 at the FVP mound are outlined separately in DAMOS Contribution #52. 

 Results from investigations at the remaining disposal mounds at the 

 CLIS site are discussed individually in the sections which follow. 



3.3.1 Stamford-New Haven North (STNH-N) 



August Survey 



REMOTS® surveys have been carried out at the STNH-N 

 disposal mound in January and August 1983, and again in September 

 1984. Nine stations located on a cross-shaped grid were occupied 

 in each of those surveys. On 9 August 1985, a survey was carried 

 out on a larger grid consisting of 17 stations (Figure 3-11) . 

 Three REMOTS® images were taken at each N, S, E, and W station, 

 while a single image was obtained at each corner station (e.g., 

 200NW) . 



Although the STNH-N disposal mound was originally capped 

 with a sand layer, most stations (37 of 43 replicates) now 

 exhibited a grain size major mode of >4 phi (coarse silt to clay- 

 sized particles) . All images from stations CTR, 200S, and one 

 image at 2 00W showed a grain-size major mode of very-fine sand. 

 Two replicates at station 200E revealed a mud/sand/mud stratigraphy 

 (Figure 3-12) ; this apparently represents the original sand cap 

 being both bioturbated and covered with more recently deposited 

 silt-clay sediments. Coarse sediments and evidence of scour were 

 observed at stations CTR and 2 00E in the last report. The images 

 from the August 198 5 survey did not show evidence of scour. One 

 replicate from station CTR showed the presence of fecal mounds at 

 the surface, suggesting that low kinetic conditions periodically 

 existed at this station. 



The mapped distribution of apparent dredged material 

 (Figure 3-11) showed the thickness of apparent dredged material 

 exceeding the penetration depth of the camera prism (20 cm) at 

 several stations. In general, this mound was intensively 

 bioturbated. Biogenic mixing of sediments made it difficult to 

 identify a distinct pre-disposal horizon, because this mixing 

 process had "erased" the pre-disposal stratum. 



Patches of highly reduced sediment were evident near the 

 sediment surface at 82% of the STNH-N stations (Figures 3-11 and 

 3-13) . The origin of this material is unknown, but its occurrence 

 suggests redistribution of reduced sediment either laterally 

 through erosion or vertically through bioturbation. Similar 

 reduced sediment patches were evident in varying levels of 

 abundance at all of the CLIS and WLIS disposal mounds surveyed in 



