In the event any dis­pute shall arise between the Oper­at­ing Engi­neers and the High­way Depart­ment and such dis­pute can­not be adjust­ed between such employ­ee and the Depart­ment, then and in such event, the dis­pute shall be report­ed to the Busi­ness Rep­re­sen­ta­tive, who shall attempt to adjust the dis­pute with the Depart­ment Super­in­ten­dent or its duly autho­rized rep­re­sen­ta­tive and if such dis­pute can­not then be set­tled, the mat­ter shall be referred to an arbi­tra­tor by the last two men­tioned rep­re­sen­ta­tives, select­ing a third arbi­tra­tor from a pan­el sub­mit­ted by the Fed­er­al Medi­a­tion and Con­cil­i­a­tion Ser­vice.  The deci­sion of this arbi­tra­tor shall be final and bind­ing on both par­ties and the expens­es of this third arbi­tra­tor shall be borne equal­ly by both par­ties.  In ren­der­ing his deci­sion, the arbi­tra­tor shall not have the author­i­ty to add to, sub­tract from, mod­i­fy, or amend any pro­vi­sion of this Agreement.