Sec. 105 (b)(1)(A) If the Secretary has reason to believe that an operator has failed to correct a violation for which a citation has been issued within the period permitted for its correction, the Secretary shall notify the operator by certified mail of such failure and of the penalty proposed to be assessed under section 110(b) by reason of such failure and that the operator has 30 days within which to notify the Secretary that he wishes to contest the Secretary's notification of the proposed assessment of penalty. A copy of such notification of the proposed assessment of penalty shall at the same time be sent by mail to the representative of the mine employees. If, within 30 days from the receipt of notification of proposed assessment of penalty issued by the Secretary, the operator fails to notify the Secretary that he intends to contest the notification of proposed assessment of penalty, such notification shall be deemed a final order of the Commission and not subject to review by any court or agency. Refusal by the operator or his agent to accept certified mail containing a notification of proposed assessment of penalty issued under this subsection shall constitute receipt thereof within the meaning of this subsection.