Hydrologic data for the Potomac Formation in New Castle County, Delaware, consist of records of historical ground-water pumpage, water levels, water quality, and surface-water discharge. This report includes records of 405 wells and hydro-graphs of water levels in 86 wells. Pumpage from 20 well fields is reported. Also included are stream-discharge hydrographs for 6 stations for water years 1979 and 1980 and historical low-flow measurements for 22 stations.
In the analysis of 23 aquifer tests, transmissivity and storage coefficient values for the Potomac Formation range from 454 to 8,480 feet squared per day and 3.8X10-3 to 5.6X10-5, respectively. Vertical hydraulic conductivities of the confining bed range from 0.0083 to 3.2 feet per day.