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s � 1. 0 INTRODUCTION Site IR. 14 (Figure 1 . 1 ), one of three sites in Indian River County, Florida, selected for development as dredged material management facilities, will provide long-term capacity for the management of sediments dredged from adjacent segments ofthe Intracoastal Waterway (ICWW) . The site-specific management plan for the I11- 14 dredged material management facility, outlined in this report, provides guidance for the development and operation of the material management area so that it efficiently processes, temporarily stores, and ultimately transfers material dredged during scheduled channel maintenance operations. To that end, this plan document addresses those facets of site design and operation which directly influence site efficiency or reduce off-site conflicts. These include elements of site preparation and facility construction, techniques ofdecantingand dewateringthe dredged material during and immediately following maintenance operations, and guidelines for post-dredging site operation and maintenance. Throughout, the goal of each phase of site management is to ensure that the site not only achieves its minimum 50-year design service life, but that it also fulfills its potential as a permanent operating facility for the intermediate storage, processing, and transfer of maintenance material dredged from the ICWW. Site I1144 was selected as the primary site to serve that portion of the ICWW in Indian River County defined in Taylor et al . ( 1997) as Reach III (Figure 1 .2). Reach III extends from a point near Vero Beach ' s northern boundary, opposite the community of Gifford (Cut IR-24, station 28+00, ICWW mile 210 . 19) southward 8 .27 miles to the Indian River/St. Lucie County line (Cut I11-35, station 31 +50, ICWW mile 218 .46). A comprehensive evaluation ofJacksonville District Corps of Engineers ' archival records confirmed that this segment of the Waterway has not been dredged since its 1959 deepening to the present 42-ft MLW project depth . Nevertheless, the most recent examination survey ( 1996) documented a total in situ reach shoal volume of 57,498 cubic yards (cy) within the authorized channel . The projected 50-year storage requirement for Reach III — 162,658 cy — represents extrapolation of the documented in situ shoaling volume multiplied by a bulking plus over-dredging factor of 2 . 15 . Thus, the IR- 14 containment basin must provide a capacity of about 163 ,000 cy.