11.6. In exercising his functions, the arbitrator may(1) interpret and apply any Act, regulation or decree to the extent necessary to resolve a matter referred to him under section 11.3;
(2) order the payment of interest, at the rate fixed under section 28 of the Act respecting the Ministère du Revenu (chapter M-31), on any amount owed to an employee pursuant to the arbitration award; (3) correct at any time a decision containing an error in writing or calculation or any other clerical error;
(4) render any other decision intended to protect the rights of the parties; and
(5) resolve any difficulty resulting from the double coverage or overlapping of fields of activity.