Mealey's (June 18, 2015, 10:37 AM EDT) -- CHEYENNE, Wyo. — The State of Colorado joined the State of Wyoming on April 21 and filed an amended petition in Wyoming federal court against the U.S. Department of the Interior (DOI) opposing new federal regulations governing hydraulic fracturing on public land (State of Wyoming v. U.S. Department of the Interior, et al., No. 15-00043, D. Wyo.)....