The 1995 box core descriptions shown in Appendix 1 corroborate the data collected in 1994, and verify the various acoustic signatures visible in the sonar images shown in Torresan and others (1995) and Figure 1. The high-backscatter material centered over the disposal sites is a heterogeneous mixture of olive-gray to gray-brown mud that acts as a binding matrix for the coarser sand to cobble-size material. The natural sediment, seen as the low back scatter region surrounding the disposal sites and most of the study area, is predominantly a beige-colored muddy carbonate sand. The high-backscatter region that is visible on the west and southwest side of the mosaic shown in Torresan and others (1995) is exposed carbonate reefs and associated sediment.

Chemical analyses completed to date do not yield definitive results, but generally, analyte concentrations are low, and many of the analytes chosen from the list of contaminants of concern are non-detectable. In some instances specific contaminants exhibit higher concentrations in native sediment, relative to dredged material and vice versa. In other instances certain analytes show both high and low concentrations in both native sediment and dredged material. Conclusions regarding the biological analyses are pending completion of those studies.

Suggestions for further studies include deployment of oceanographic instrumentation to evaluate the types of current activity responsible for the array of wavy bedforms observed in the sonar images, subbottom profiles and video and still photographs. This will allow the quantification of the bottom flow that can potentially resuspend and redistribute the dredged material and any associated contaminants.�

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