United states department of interior bureau of ocean energy management
West Belle Headland Renourishment Area
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1.4.3West Belle Headland Renourishment AreaAfter reviewing recent Barrier Island Comprehensive Monitoring Program Survey data, the Project team determined that the previously restored template of the CWPPRA TE-52 West Belle project (CPE 2009 and 2013) may require a renourishment event; therefore the West Belle Headland Renourishment Area is included in the permit application for this action. The proposed activity would add new sand to existing beach, dune, and marsh habitat (Figure 2-6). The beach and dune features include the dune which is approximately 8,400 linear feet in length, constructed at a target elevation of +7.5 ft NAVD88, with fore- and back-slopes of 1V:25H and a typical width of 100 ft at the crest, Figure 2-8.bThe target elevation of the beach will be +5.0 ft NAVD88, with a slope of 1:25 from the beach berm crest extending seaward to the intersection with the existing grade, and a typical width of 292 ft. The volume of sand from Ship Shoal and/or South Pelto Borrow Area required to construct the beach and dune would be approximately 0.6 MCY. Assuming a 1.3:1 cut to fill ratio and being conservative in the permitting, the recommended cut volume requirements for the sand source are 0.8 MCY. The marsh feature for the West Belle Headland Renourishment Area is approximately 7,200 linear feet in length, north of the beach and dune, and involves placement of approximately 0.4 MCY of mixed sediments to create intertidal marsh habitat. The marsh platform target elevation is +3.0 ft NAVD88 with an average width of approximately 1,500 ft. Containment dikes will be constructed from sediment excavated in situ. The marsh containment dike dimensions are +5.5 ft NAVD88 elevation, 10 ft crest width, with 1V:10H side slopes. An exterior containment dike borrow channel is proposed as the source of in situ sediment for dike construction. Assuming a 1.6:1 cut to fill ratio and being conservative in the Preliminary Design Phase, the recommended cut volume from Ship Shoal and/or South Pelto Borrow Area requirements for the mixed sediments source were calculated at 0.6 MCY. Figure 2‑8. West Belle Headland Renourishment Typical Cross Sections 
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