The commissioners court of a county may:
(1) require a permit for trucks that transport grease trap, sand trap, and septic waste, including trucks serving unincorporated areas of the county;
(2) by order establish guidelines and procedures for issuing permits to trucks that transport grease trap, sand trap, and septic waste; and
(3) issue a single permit number that allows a municipality participating in the county regulatory program the option to add to that permit number a suffix unique to the municipality.