The department may issue a conforming permit for a sign, display, or device erected within a zoned commercial or industrial area acceptable for outdoor advertising purposes as provided in §§ 31-29-71.8 to 31-29-71.12 , inclusive, or within an "unzoned commercial or industrial area" as defined in § 31-29-70 if the sign display or device is otherwise lawfully erected and maintained. Source: SL 1986, ch 240 , § 4.