About the data in GRN

public drinking water supply well data from the early 1970s to present from DNR's drinking water data system,
private drinking water supply wells, non-point source priority watershed projects and special groundwater studies data from 1988 to present,
landfill monitoring wells from the mid–1970s to present that have been entered into DNR's Groundwater and Environmental Monitoring System (GEMS), and
monitoring wells at wastewater treatment facilities and land treatment sites from the mid–1970s to present from DNR's System for Wastewater Applications, Monitoring and Permits (SWAMP).

Additional data from the Leaking Underground Storage Tank (LUST), spills and remediation sites may be found in site-specific files. Use the Bureau for Remediation and Redevelopment Tracking System (BRRTS) to identify files that may contain additional data.
Some of the samples retrievable through this system are groundwater prior to treatment and some are groundwater after treatment. For example, some samples from public wells might be taken after treatment and private well samples might be taken at a tap after softening or other home treatment.
You will get an error message if the search criterion returns too many records to display. Please use additional search criteria options to reduce the number of records per retrieval.
See the GRN Glossary for a list of terms used in GRN and their definitions.