How do I know if a vacancy is represented by a union? Each individual Civil Service vacancy posted on our website indicates whether or not the position is represented and, if so, by which union. What unions currently have bargaining agreements with SIU School of Medicine? Currently, the International Union of Operating Engineers (IUOE), Local 399, represent approximately 44 Civil Service employees in the engineering and service/maintenance areas. The American Federation of State, County and Municipal Employees (AFSCME), Local 370, represents approximately 680 Civil Service employees in other