Four prisoners serving time in the Prairie County Jail were remanded to the Department of Correction after failing a random drug test Friday afternoon. Clay Brummett and Garry Hill, both 44; Robert Hughes, 28, and Daniel Zarlingo, 38, were part of the state`s 309 program which allows prisoners to work in the jail under supervision. The men were considered model prisoners despite being convicted on drug-related charges. Prairie County Sheriff Riley Seevers wouldn`t say what drugs the men tested positive for or how they got the drugs. An investigation is ongoing.