Kentucky Geological Survey Report of Investigations


A carbon dioxide injection test well was drilled in 2009 to a depth of 8,126 ft below ground surface in Hancock County, Kentucky. Six hundred ninety tons of CO2 was successfully injected into Knox Group saline aquifers. Two domestic wells (MB and GB) and two domestic springs (CA and RC) were sampled to monitor any potential changes in groundwater quality associated with possible migration of CO2 from deeper saline aquifers into shallow freshwater aquifers. The four sites were sampled for pH, bicarbonate, total dissolved solids, turbidity, anions, total dissolved metals, dissolved inorganic carbon, total CO2, and delta carbon-13 of the dissolved inorganic carbon (δ13CDIC). Values of pH for the four sites ranged between 4.58 and 7.82 and were consistent over time at all sites. Bicarbonate, total CO2, dissolved inorganic carbon, and TDS concentrations showed very little variation over time at all of the sites except at well MB. although water chemistry at well MB varied during the monitoring period, δ13CDIC values suggested that injectate had not migrated into the shallow aquifer at that site. All groundwater geochemical data clearly indicate that injectate CO2 had not migrated upward into the four monitored shallow aquifers before sampling was discontinued in August 2012.

Publication Date



Series XII

Report Number

Report of Investigations 31

Digital Object Identifier (DOI)