An appointment shall be for a four-year term. A committee member may serve successive terms. Each member shall serve on the committee until the appointment and qualification of their successor. A vacancy occurring prior to the expiration of the terms shall be filled by appointment for the unexpired term. The director, upon the recommendation of the committee by a two-thirds vote, may remove an appointee member for misconduct in office, incompetency, neglect of duty, or other sufficient cause after due notice and hearing.