49 CFR § 209.121 - Appeal.
(a) Any party aggrieved by a presiding officer's decision or order issued under § 209.117 assessing a civil penalty may file an appeal with the Administrator. The appeal must be filed within twenty (20) days of service of the presiding officer's order.
(b) Prior to rendering a final determination on an appeal, the Administrator may remand the case for further proceedings before the hearing officer.
(c) In the case of an appeal by a respondent, if the Administrator affirms the assessment and the respondent does not pay the civil penalty within twenty (20) days after service of the Administrator's decision on appeal, the matter may be referred to the Attorney General with a request that an action to collect the penalty be brought in the appropriate United States District Court.