GSA Hydrogeology Division - Programs, awards,and 2x/year newsletter of the Geological Society of America Hydrogeology Division.
Illinois Groundwater Consortium - Working toward providing a scientifically valid basis for agricultural chemical management and regulatory decisions affecting groundwater.
National Ground Water Association - Groundwater scientists and engineers, as well as manufacturers and contractors in the water well industry.
Wisconsin Ground Water Association - Non-profit volunteer organization advancing understanding of Wisconsin's ground water (scientific, technical, legal, educational, and public policy aspects).
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