{"name":"Calhoun Research & Development Drilling Activity in Brown County, Illinois","publisher":"Buckhead Energy","url":"https://www.buckheadenergy.com/operators/calhoun-research-development/illinois/brown-il","license":"https://creativecommons.org/licenses/by/4.0/","dataAsOf":"2026-08-06","source":"Public state oil & gas well-header records (permits, spuds, completions).","operator":"Calhoun Research & Development","operatorSlug":"calhoun-research-development","state":"IL","county":"Brown","totalWells":46,"producingWells":0,"permits24mo":0,"spuds24mo":0,"ducCount":0,"topFormation":null,"rankInCounty":2,"firstPermitDate":"1982-02-08","lastPermitDate":"2008-05-27"}