46 U.S.C. § 3716: Tank washings

(a) A vessel may not transfer cargo in a port or place subject to the jurisdiction of the United States if, before arriving, the vessel has discharged tank washings containing oil or hazardous material in preparation for loading at that port or place in violation of the laws of the United States or in a manner or quantities inconsistent with a treaty to which the United States is a party. (b) The Secretary shall establish effective control and supervisory measures to carry out this section.