(1) Signs and their supporting structures erected or maintained in violation of this act may be removed by the department in the manner prescribed in this section.

    (2) There shall be mailed to the owner of the sign by certified mail a notice that the sign or its supporting sign structure violates stated specified provisions of this act and is subject to removal. If the owner's address cannot be determined, a notice shall be posted on the sign. The posted notice shall be written on red waterproof paper stock of a size not less than 8-1/2 inches by 11 inches. The notice shall be posted in the area designated by section 12 for the placing of permit numbers, in a manner so that it is visible from the highway faced by the sign or sign structure.

    (3) If the sign or sign structure is not removed or brought into compliance with this act within 60 days following the date of posting or mailing of written notice or within such further time as the department may allow in writing, the sign or sign structure shall be considered to be abandoned.

    (4) The department shall conduct a hearing pursuant to the administrative procedures act of 1969, 1969 PA 306, MCL 24.201 to 24.328, at which it shall confirm that the sign is abandoned, that due process has been observed, and that the sign may be removed by the department without payment of compensation and at the expense of the owner. Signs or sign structures considered abandoned, and any other sign or sign structure erected or maintained in violation of this act that is not eligible for removal compensation as provided in section 22, shall be removed by the department forthwith or upon the expiration of such further time as the department allows. The department may recover as a penalty from the owner of the sign or sign structure or, if he or she cannot be found, the owner of the real property upon which the sign or sign structure is located, double the cost of removal or $500.00, whichever is greater. For frivolous hearings as determined by the administrative law judge, the department may recover as a penalty from the owner of the sign or sign structure, or, if the owner of the sign or sign structure cannot be found, the owner of the real property upon which the sign or sign structure is located, double the cost of an administrative hearing incurred by the department or $500.00, whichever is greater. Any penalty imposed under this section is subject to de novo review in circuit court.

    (5) The department, its agents and employees, and any person acting under the authority of or by contract with the department may enter upon private property without liability for so doing in connection with the posting or the removal of any sign or sign structure pursuant to this act.

    (6) The department may contract on a negotiated basis without competitive bidding with a permittee under this act for the removal of any sign or sign structure pursuant to this act.

    (7) Any repeat violation of this act shall be considered a continuing violation of this act.

    (8) A sign or sign structure erected or maintained in violation of this act is a nuisance per se. The department, before or after a hearing is conducted, may apply to the circuit court in the county in which a sign is located for an order to show cause why the use of a sign erected or maintained in violation of this act should not be enjoined pending its removal in accordance with this section.