CLE Engineering, Inc. (CLE) provided services for the maintenance dredging of the existing terminal berth at the Holcim (US), Inc. Cement Facility located in Flushing Bay in Queens, NY. Approximately 7,100 CY of sediment was mechanically dredged and placed in a hopper barge so that free water could be pumped into an adjacent decanting scow. Sediments were then towed via tug to the Clean Earth Dredging Technologies Facility located in Jersey City, NJ where they were processed/dewatered utilizing 8% Portland cement. Treated sediments were beneficially reused as fill at the DuPont-Grasselli site located in Linden, NJ.
A 12-inch thick sand cap was placed over dredged areas to address the concerns raised by the New York State Department of Environmental Conservation over the potential for the exposure of in-situ contaminants as a result of maintenance dredging efforts. CLE performed pre- and post-dredge and capping surveys using multi beam technology and confirmed final capping thickness using vibrocores. The project was completed in January 2015.