McCook County Study

Project Description

New test hole drilling and aquifer mapping are currently ongoing within McCook County. Historical and recent test-hole data, aquifer maps, bedrock maps, and publications are being used to produce an updated set of 1:100,000 scale maps of the surface geology, bedrock geology, and aquifer boundary maps. These maps will be complemented with a technical report, further detailing the geology and hydrology within McCook County. Subsurface information is obtained through drilling test holes accompanied by a written descriptive analysis of the materials drilled. GIS analysis and field survey methods are used in conjunction with the test hole data to yield a thorough investigation of McCook County. McCook County test holes and observation wells are being drilled to refine aquifer boundaries and bedrock contacts, with the final revisions of all McCook County Study maps and reports occurring post-drilling.

Observation wells in McCook County are used for water quality and water level analysis. Water levels taken are tied to feet above mean sea level to obtain a water level elevation. These water level elevations are used to differentiate separate aquifers from one another if the elevations are distinctly different.