Initially, the land where the landfill was located was a salt marsh in which there were tidal wetlands, forests, and freshwater wetlands. The subsoil was made up of clay, with sand and silt as the top layer of soil. The tidal marsh, which helped to clean and oxygenate the water that passed through it, was destroyed by the dump. The fauna were largely replaced by herring gulls. The native plant species were driven out by the common reed, a grass which grows abundantly in disturbed areas and can tolerate both fresh and brackish water. The stagnant, deoxygenated water was also less attractive to waterfowl, and their population decreased. Samuel Kearing, who had served as sanitation commissioner under Mayor John V. Lindsay, remembered in 1970 his first visit to the Fresh Kills project: