Management Plan for the Disposal of Contaminated Material in the Craney Island Dredged Material Management Area

Book excerpt: The Craney Island Management Plan was developed to extend the life of the Craney Island Dredged Material Management Area (CIDMMA). The CIDMMA is used to dispose maintenance and new work dredged material from the project area. With current practice, CIDMMA would reach ultimate capacity by the year 2000. If, however, suitable material is barged to the sea and only contaminated material is placed in the facility (Restricted Use Program), then the life of the facility can be extended. Two tasks were addressed in this study: (a) determine service life under Restricted Use and (b) determine contaminant losses and conduct a Comprehensive Analysis of Migration Pathways (CAMP) expected to occur under Restricted Use. The results showed that the service life of the CIDMMA could be extended under Restrictive Use for approximately 140 years under baseline coniditions or 90 years under Worst Case conditions. The CAMP analysis was conducted along three major contaminant migration pathways (effluent, leachate, and volatile). Effluent was the most significant pathway for metal losses and volatilisation and for polynuclear aromatic hydrocarbon (PAH) losses. Leachate losses under a fully dewatered condition would not exceed effluent losses for some metals. PAH losses for a fully dewatered condition would not exceed effluent losses.