State corrections officials plan to close four more prisons in response the shrinking number of drug offenders behind bars. The state Department of Corrections and Community Supervision announced plans Friday to close the minimum-security Monterey Shock facility in Schuyler County and three medium-security facilities: Butler in Wayne County, Chateaugay in Franklin County and Mt. McGregor in Saratoga County. Officials cite a dramatic reduction in drug offenders in those prisons. The prisons will remain open for a full year, giving administrators time to transfer inmates to others. Officials say they want to prevent layoffs by moving employees to other facilities.