Alternative 4 (continued)
Barrier Island Ecology & Habitat Diversity	Same impacts as Alternative 3.
	Provides interest in the form of greater topography.
	Addition of open-water ponds expands the suite of habitats and wildlife, thus increasing diversity.
Storm Damage Reduction	Addition of a continuous dune ridge of any dimension, superimposed on existing topography, improves storm-surge protection and reduces potential storm damages. The degree of storm-damage reduction is significant even with a dune crest at 14 ft above mean sea level (see Section 5.5). The impact of increased dune elevation on storm-surge attenuation is much greater than the effect of higher vegetation.
Ocean Views	Same impacts as Alternative 3.
	Offers new views over ponds for a greater variety of vistas
Beach Access & Public Safety	Same impacts as Alternative 3.
Fire	Improved impacts compared with Alternative 3 because of the addition of ponds, which form a natural barrier and water supply in the event of fire.
Pests	Same impacts as Alternative 3.
Property Values	Improved impacts compared with Alternative 3 because of added storm-surge protection and the added amenity of ponds, which enhance the landscape.
Cost of Implementation	Vegetation changes would entail similar costs as Alternative 3.
Alteration of topography involves earth moving, which could be limited to construction of a simple low dune (see Section 5.5) or could involve more extensive sculpting of the land and construction of multiple dune ridges. Excavation for ponds could provide the sand for dune construction, thus minimizing transportation costs.
Accreted shoals along the beach are another potential sand source (subject to federal and state permits). Earthworks landward of state jurisdictional lines would involve less time and expense in securing necessary approvals.
Construction Requirements	Modification of topography would involve excavation and filling along with vegetation removal and replanting.
	Ponds and dunes could be constructed entirely using land-based equipment with the major work occurring during winter. Projects involving dozens of acres and 100,000-400,000 cy of earthworks could be accomplished in a relatively short time frame (1-3 months).
	Replanting and establishment of grass vegetation could be accomplished in 1–2 growing seasons.