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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 IR- 14 ' 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 IR- 14 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