This report contains data pertaining to the geologic and hydrologic characteristics of the bedrock aquifers of the Denver basin at a site near Castle Pines, Colorado. Data consist of a lithologic- description of about 2,400 ft of drill core and laboratory determinations of mineralogy, grain size, bulk and grain density, porosity, specific yield, and specific retention for selected core samples. Water-level data, atmospheric-pressure measurements, aquifer-compression measurements, and borehole geophysical logs also are included.