A 37-year-old Knoxville resident was charged with conspiracy to manufacture methamphetamine Tuesday. The Marion County Sheriff’s Office tells KNIA/KRLS News that Colleen Marie Augustine was arrested with 32-year-old Bussey resident Tony Shane Silvers and three others in Oskaloosa after an investigation showed they were purchasing pseudoephedrine in Des Moines Tuesday with the purpose of making meth later that night. The Mahaska County Sheriff’s Office, Marion County Sheriff’s Office, and South Central Iowa Drug Task Force assisted in the investigation, among other agencies.