P. B. Daddow 1986 Groundwater resources in the Hanna and Carbon Basins of Wyoming were assessed in a study from 1974 through 1980 because of the development of coal mining in the area. Data collected from 105 wells during that study, including well-completion records, lithologic logs, and water levels, are presented. The data are from stock wells, coal-test holes completed as observation wells by the U.S. Geological Survey. The data are mostly from mined coal-bearing formations: the Tertiary Hanna Formation and the Tertiary and Cretaceous Ferris Formation. Well-completion data and lithologic logs were collected on-site during drilling of the wells or from U.S. Geological Survey files, company records, Wyoming State Engineer well-permit files, and published reports. (USGS) application/pdf 10.3133/ofr85628 en U.S. Geological Survey, Ground-water data for the Hanna and Carbon basins, south-central Wyoming, through 1980 reports