Chloride content of water from wells screened in the Lloyd sand member of the Raritan formation on Long Island, New York

Since 1932 the United States Geological Survey, in cooperation with the New York Power and Control Commission, the Nassau County Department of Public Works, the Suffolk County Board of Supervisors, and later also the Suffolk County Water Authority, has been making general and specific studies dealing with the occurrence, movement, quantity, quality, and temperature of ground water found in several water-bearing formations on Long Island. In the first years most of the emphasis was placed on studying the shallow water-table beds, although geologic and hydrologic information was obtained for the Lloyd sand member of the Raritan formation, the deepest water-bearing beds on Long Island, as well as for other shallower artesian formations.