On and after October 28, 1991, notwithstanding any other provision of law, employees of the agencies of the Department of Agriculture, including employees of the Agricultural Stabilization and Conservation county committees, may be utilized to provide part-time and intermittent assistance to other agencies of the Department, without reimbursement, during periods when they are not otherwise fully utilized, and ceilings on full-time equivalent staff years established for or by the Department of Agriculture shall exclude overtime as well as staff years expended as a result of carrying out programs associated with natural disasters, such as forest fires, droughts, floods, and other acts of God.