(a) A petition for review of a notice of proposed individual civil penalty assessment must be filed within 30 days of its service on the individual.

(b) No extension of time will be granted for filing a petition for review of a notice of proposed individual civil penalty assessment. Failure to file a petition for review within the time period provided in paragraph (a) shall be deemed an admission of liability by the individual, whereupon the notice of proposed assessment shall become a final order of the Secretary and any tardy petition shall be dismissed.