Preventing Negative Impacts on High-capacity Wellfields from Geothermal Heat Pump System Installations

The new Federal residential and commercial geothermal tax credits are causing a lot of people to install new and retrofitted geothermal heat pump systems right now.  Many of these retrofitted geothermal systems are located within the capture zones (area of direct ground-water flow to the well) of public water-supply well fields serving tens of thousands of people.  Improperly constructed geothermal boreholes have been identified as one of the top three threats to public ground-water supply well fields in source water protection studies.  Proper grouting of the geothermal heat pump system vertical heat-exchanger boreholes prevents both surface and subsurface contaminants from entering the aquifer and prevents the high-capacity well field from producing contaminated groundwater.