Keough -- who was busted in Coto de Caza, CA driving three times over the legal limit -- was charged with "one felony count DUI with a prior felony DUI conviction within 10 years" and one felony count driving with a BAC of .08 or higher.
According to the Orange County D.A., "Keough was also charged with sentencing enhancements for having a blood alcohol level of .20 percent or more and a prior 2005 felony DUI conviction."
Technically, the D.A. says Keough had a BAC of .30 "an hour after" his traffic stop.
Keough faces three years in state prison if convicted -- he'll be arraigned on November 2.