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� l four to six weeks to complete each dredging operation . Immediately upon completion ofdredging, the dredge discharge pipeline will be removed. The return pipeline will remain in place to transport water decanted from the containment basin or released by initial trenching procedures (Section 4. 1 ). After completion ofthis procedure, approximately four to six weeks beyond the completion of dredging, the return pipeline will also be removed . Ponded stormwater collected in the containment area will be subsequently removed via the weir system so that any suspended sediment will be retained in the containment basin. However, unlike the clarified effluent removed during dredging operations, stormwater will be routed to the on-site mangrove impoundment via the perimeter ditch . The removal of runoff is discussed further in Section 4 .2 . 1 . 3 .2 Inlet Operation The quality of the dredged sediment; specifically, the settling characteristics of the different gramn size fractions, will primarily determine the operation of the inlet pipe. The coarsest fraction of the material will settle out of suspension very rapidly and form a mound near the inlet. Successively finer fractions, characterized by lower settling velocities, will be deposited closer to the outlet weir. Thus, absent an inlet operation strategy, the dominant grain-size fraction will determine the distribution of sediment within the basin. For example, if fine-grained sediments dominate, a relatively large volume of material may be concentrated nearest the weirs . An extensive concentration of fine-grained sediment may require specialized dewatering procedures to speed drying. As discussed in Section 2. 3 . 3 , analysis of samples taken at three locations within Reach III suggests that channel sediments in this reach contain significant fine-grained material . Mean grain diameters of individual samples ranged between 0 . 104 mm (Station I11-3 -3 , categorized as fine sand) and 0.031 mm (Station IR-3 -2, categorized as silt). The silt-sized fraction (i .e. , particles <0. 074 mm diameter) comprised between 19 and 80% of the total . The one sample subjected to chemical analysis (Station IR- 1 - 1 ) yielded an organic matter content of 3 % . Additional data characterizing specific channel shoal sediments will be obtained before future dredging operations. These data will include, at a minimum, core boring logs containing a qualitative categorization of each sediment strata ; laboratory data, including sediment size 28