undeveloped coastal barrier

(A) a depositional geologic feature (such as a bay barrier, tombolo, barrier spit, or barrier island) that—

(i) is subject to wave, tidal, and wind energies, and

(ii) protects landward aquatic habitats from direct wave attack; and

(B) all associated aquatic habitats, including the adjacent wetlands, marshes, estuaries, inlets, and nearshore waters;

but only if such feature and associated habitats contain few manmade structures and these structures, and man's activities on such feature and within such habitats, do not significantly impede geomorphic and ecological processes.