The department shall pay all expenses for the issuance of such notices and the conduct of such hearings and referenda and shall supervise the conduct of such hearings and referenda. It shall issue appropriate regulations governing the conduct of such hearings and referenda and providing for the registration prior to the date of the referendum of all eligible voters or prescribing some other appropriate procedure for the determination of those eligible as voters in such referendum. No informalities in the conduct of such referendum or in any matters relating thereto shall invalidate the referendum or the result thereof if notice thereof shall have been given substantially as provided in § 48-9-540 and such referendum shall have been fairly conducted.