Groundwater levels and field-determined groundwater-quality characteristics from the Great Miami buried-valley aquifer, Southwestern Ohio, 1999, 2000, 2019, and 2020

The U.S. Geological Survey (USGS), in cooperation with the Miami Conservancy District, Dayton, Ohio, in 2019 and 2020 investigated the concentrations of per- and polyfluoroalkyl substances (PFAS) and related water chemistry in groundwater from the Great Miami buried-valley aquifer (GM-BVA) of southwestern Ohio. Data in this release include groundwater parameters, including groundwater level, temperature, pH, dissolved oxygen, turbidity, and specific conductance, collected during the 2019-2020 water sampling and comparison data from prior, 1999-2000 sampling of the same wells. The 23 wells used for sampling were identified and sampled previously by the USGS National Water-Quality Assessment Program, starting in 1999, to assess the occurrence of a variety of inorganic and organic contaminants in the GM-BVA. Sampled wells were from parts of the GM-BVA in Butler, Champaign, Clark, Greene, Hamilton, Miami, Montgomery, Shelby and Warren counties in the Great Miami River, Little Miami River, and Whitewater River Basins.