On September 30, 2019 the United States District Court Eastern District of Missouri issued its Memorandum Opinion and Order requiring Ameren Missouri to install flue gas desulfurization on the Rush Island power plant and dry sorbent injection on the Labadie power plant. It had previously been determined that Ameren Missouri did not file a PSD permit when it should have and should have installed BACT for SO2. Dr. Jim Staudt testified as the United States’ expert on Best Available Control Technology, and testified that BACT was an emission rate achieved through wet FGD. Ameren had previously performed engineering studies to determine the possible emission rates and cost of FGD that were utilized in the case. Dr. Staudt also evaluated means of mitigating past harm, to include controls on Labadie station. In the opinion, Judge Sippel found Dr. Staudt’s testimony to be credible and in his opinion states, “I heavily rely on Dr. Staudt’s testimony when discussing facts surrounding BACT determinations in this case.” The Memorandum and Opinion is shown here.