(1) A notice of proposed adverse action issued pursuant to 16-4-107, 16-4-406, 16-4-407, or 16-4-1008, MCA, shall be served upon the licensee or registrant of record or, in the case of an application for a new license, on the applicant, by sending a copy of the notice to the licensee, registrant, or applicant by certified mail to the mailing address on file with the department.

(2) Service shall be considered complete three days after mailing the notice. Service shall not be considered incomplete because of refusal to accept delivery of the notice.

(3) The licensee, registrant, or applicant must respond to the department in writing within 20 days of service of the notice of proposed adverse action. Failure to respond will result in the enforcement of the administrative action proposed in the notice.