The corn shall not be removed from the port of entry, nor shall any bag or other container thereof be broken or opened, except for the purpose of sterilization, until a written notice is given to the United States Collector of Customs, or, in the case of Guam, the Customs officer of the Government of Guam, by an inspector of the Plant Protection and Quarantine Programs, that the corn has been properly sterilized and released for entry without further restrictions so far as the jurisdiction of the Department of Agriculture extends thereto. All apparatus and methods for accomplishing such sterilization must be satisfactory to the Plant Protection and Quarantine Programs. Corn will be delivered to the permittee for sterilization, upon the filing with the appropriate customs official of a bond in the amount of $5,000, or in an amount equal to the invoice value of the corn if such value is less than $5,000, with approved sureties, and conditioned upon sterilization of the corn under the supervision and the satisfaction of an inspector of the Plant Protection and Quarantine Programs; and upon the redelivery of the corn to said customs official within 40 days from the arrival of the corn at the port of entry.