Karst Research at the Kentucky Geological Survey
Karst research at the Kentucky Geological Survey has expanded in both scope and coverage during the last decade. Chuck Taylor, head of the Water Resources Section, is establishing a network of groundwater monitoring stations across Kentucky. Seven of the wells in the network are drilled into karst aquifers and one karst spring is currently being monitored. Efforts are under way to establish more stations at springs and wells.
Among the ongoing projects is a Karst Atlas, which is composed of several plates (depicting groundwater basins, cover-collapse frequency, flooding, etc.), as conceptualized by Jim Currens, karst hydrogeologist. Final drafts of the four remaining groundwater basin (30 X 60 minute quadrangles) maps (Madisonville-Paducah, Corbin, Morehead, and Tompkinsville) are planned to be finished by early 2017. The Karst Potential Index, now online, is another plate in the Karst Atlas.
Hydrogeologist Junfeng Zhu is making progress on using newly available LiDAR terrain elevation data to map previously unrecognized sinkholes in parts of Kentucky. Last year, LiDAR-delineated sinkholes in Bullitt, Jefferson, and Oldham Counties were mapped, resulting in an additional 4,140 sinkhole features being added to the KGS online map server. This year, 1,821 sinkholes for Fayette County were identified from LiDAR data.
In addition to the Karst Atlas work, Jim Currens is investigating and documenting the occurrences of cover-collapse sinkholes in the state; he examined 13 such features in 2015 and 13 to date in 2016. A report on the distribution of these sinkholes and possible factors that contribute to their occurrence is in preparation and should be published by early 2017.
Earlier work by KGS staff resulted in a series of maps depicting time-of-travel maps for traces to Royal Spring in Georgetown, the main water supply for Scott County. This study determined the length of time for injected tracers to arrive at Royal Spring under variable flow conditions from a finite set of injection points scattered across the watershed of the karst aquifer. The purpose of the study was to provide an estimate of how long it will take for a reported contaminant spill (of a water-soluble compound) to arrive at the spring. This allows the Georgetown Municipal Water and Sewer Service to better manage its water resources during a pollution incident.
Other ongoing work is a hydrogeologic monitoring report by Jim Currens on the Royal Spring or Cane Run watershed/springshed. In addition to these activities, Currens assists the general public by answering inquiries about sinkhole occurrences and conducting site inspections.