Relation between Land Use and Quality of Shallow, Intermediate, and Deep Ground-Water in Nassau and Suffolk Counties, Long Island, New York

摘要

This report presents the results of the third phase of investigation of theeffects of land use on ground-water quality in Nassau and Suffolk Counties. Also included are: (1) descriptions of the five study areas in terms of land use, population density, and hydrogeology; (2) estimates of ground-water traveltime from the water table to the midpoint of each well screen for 207 randomly selected wells; (3) comparisons of the chemical quality of water from the shallow zone of each study area with that in the underlying intermediate zone; and (4) comparisons of the chemical quality of water from the shallow zones of the three suburban areas with that in the underlying intermediate and deep zones. Also discussed in the report is whether effects of development on shallow ground water observed in previous studies are evident in intermediate and deep zones of the aquifer and whether sewers affect water quality in the three suburban areas. Water-quality data collected by USGS investigators from 207 randomly selected wells screened in shallow, intermediate, and deep zones beneath the five study areas are evaluated in this report.