This report is a summary of the historical development, from 1949 to 2001, of the U.S. Geological Survey's (USGS) hydrologic monitoring and investigative programs at the Idaho National Engineering and Environmental Laboratory. The report covers the USGS's water-level monitoring program, water-quality sampling program, geophysical program, geologic framework program, drilling program, modeling program, surface-water program, and unsaturated-zone program. The report provides physical information about the wells and information about the frequencies of sampling and measurement. Summaries of USGS published reports with U.S. Department of Energy (DOE) report numbers also are provided in an appendix. This report was prepared by the USGS in cooperation with the DOE.