(a) Penalties for failure The owner, agent, consignee, charterer, master, or commanding officer of any vessel or aircraft arriving in the United States from any place outside thereof who fails
(1) to detain on board the vessel, or in the case of an aircraft to detain at a place specified by an immigration officer at the expense of the airline, any alien crewman employed thereon until an immigration officer has completely inspected such alien crewman, including a physical examination by the medical examiner, or
(2) to detain any alien crewman on board the vessel, or in the case of an aircraft at a place specified by an immigration officer at the expense of the airline, after such inspection unless a conditional permit to land temporarily has been granted such alien crewman under section
1282 of this title or unless an alien crewman has been permitted to land temporarily under section
1182 (d)(5) or
1283 of this title for medical or hospital treatment, or
(3) to remove such alien crewman if required to do so by an immigration officer, whether such removal requirement is imposed before or after the crewman is permitted to land temporarily under section
1182 (d)(5),
1282, or
1283 of this title, shall pay to the Commissioner the sum of $3,000 for each alien crewman in respect to whom any such failure occurs. No such vessel or aircraft shall be granted clearance pending the determination of the liability to the payment of such fine, or while the fine remains unpaid, except that clearance may be granted prior to the determination of such question upon the deposit of a sum sufficient to cover such fine, or of a bond with sufficient surety to secure the payment thereof approved by the Commissioner. The Attorney General may, upon application in writing therefor, mitigate such penalty to not less than $500 for each alien crewman in respect of whom such failure occurs, upon such terms as he shall think proper.