The effort to change the makeup of the commission was the result of a decision it made to strip a large-scale animal feeding lot of its permit. The Missouri Department of Natural Resources issued a permit in August 2015 to Trenton Farms, a corporation in Pipestone, Minn., to build a facility to house 6,000-plus hogs in rural Grundy County, near the Iowa border. The concentrated animal feeding operation, or CAFO, would generate more than 90 tons of manure each year along with millions of gallons of wastewater. The permit was then sent to the seven-member Clean Water Commission. Its job is to adopt regulations and policies to carry out the objectives of the federal Clean Water Law. On a 4-2 vote, the commission revoked the permit, saying the corporation behind the application had not proved it had the assets to maintain the facility or pay to clean up any potential accidents.