{"name":"Union Oil Company Of California Drilling Activity in Clay County, Illinois","publisher":"Buckhead Energy","url":"https://www.buckheadenergy.com/operators/union-oil-company-of-california/illinois/clay-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":"Union Oil Company Of California","operatorSlug":"union-oil-company-of-california","state":"IL","county":"Clay","totalWells":402,"producingWells":0,"permits24mo":0,"spuds24mo":0,"ducCount":0,"topFormation":null,"rankInCounty":2,"firstPermitDate":"1969-08-13","lastPermitDate":"2012-05-25"}