Either the Employer or the Association or both shall notify the arbitrator of their selection and upon their acceptance shall forward to the arbitrator a copy of the grievance, the Employer's answer at Step Three, the Association's notice to the Director of Labor Relations as provided for in this section, and a copy of the Agreement. A copy of this communication, except a copy of the Agreement, shall be sent to either the Employer or the Association as the case may be. In the event the arbitrator does not accept being selected, the selection process shall be repeated until an arbitrator has accepted selection.