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� a 4. 0 POST-DREDGING SITE MANAGEMENT The post-dredging phase of site operation begins following the completion of decanting and continues until the start of the next planned dredging event. Post-dredging site management will be accomplished through the joint efforts of the FIND and the Jacksonville District, COE, and will include, at a minimum , quarterly site inspections . Additional post-dredging site management tasks are discussed in the following section . During the post-dredging phase, dredged material deposited within the containment basin is actively managed to reduce its moisture content. Through this process, the material is made suitable for handling and removal, should market conditions prove favorable . However, Site IR44' s intended use as a permanent facility requires other management procedures between successive dredging operations. These include a comprehensive monitoring and data collection effort, mosquito control, and site security. Each element of post-dredging site management is discussed below . 4. 1 Dewatering Operations Dewatering techniques to be used at Site IR- 14 depend on the physical characteristics of the dredged material . As discussed in Section 2 .3 .3 , preliminary data indicate that the material to be placed in the IR44 containment basin may contain up to 80% silts and clays (i .e . , particles <0 . 074 mm in diameter), with organics comprising up to 3 % . This fine-grained fraction will be the most resistant to drying. The relatively thin deposition layer resulting from a typical dredging operation (<2. 0 ft, Section 3 . 3 ) suggests that the coarser sediment fraction will likely dry through natural evaporation and percolation alone . However, effectively lowering the moisture content of the fine-grained fraction will likely still require supplementary dewatering techniques . The most appropriate dewatering techniques for this purpose include surface water removal , progressive trenching to promote continued drainage, and progressive reworking or removal of the dried surface layer. Each procedure and its specific application to the present situation are discussed below . Decanting all ponded surface water is necessary before significant evaporative drying of the fine- grained material can occur . Simply continuing to lower the weir crest will remove most of the ponded water following the completion of dredging operations. However, the anticipated topography of the deposition 36