19 U.S.C. § 1312: Bonded smelting and refining warehouses

Any plant engaged in smelting or refining, or both, of metal-bearing materials as defined in this section may, upon the giving of satisfactory bond, be designated a bonded smelting or refining warehouse. Metal-bearing materials may be entered into a bonded smelting or refining warehouse without the payment of duties thereon and there smelted or refined, or both, together with metal-bearing materials of domestic or foreign origin. Upon arrival of imported metal-bearing materials at the warehouse they shall be sampled according to commercial methods and assayed, both under customs supervision. The bond shall be charged with a sum equal in amount to the duties which would be payable on such metal-bearing materials in their condition as imported if entered for consumption, and the bond charge shall be adjusted to reflect changes in the applicable rate of duty occurring while the imported materials are still covered by the bond. the total amount of customs duties owed on the materials on importation into the United States, or the total amount of customs duties paid to the USMCA country on the product, and 100 percent during the 8-year period beginning on January 1, 2004 , 75 percent during the 1-year period beginning on January 1, 2012 , 50 percent during the 1-year period beginning on January 1, 2013 , and 25 percent during the 1-year period beginning on January 1, 2014 , or upon payment of duties on the dutiable quantity of metal contained in the imported metal-bearing materials, or upon the transfer of the bond charges to another bonded smelting or refining warehouse by physical shipment of a quantity of the same kind of metal contained in any product of smelting or refining of metal-bearing materials equal to the dutiable quantity contained in the imported metal-bearing materials less wastage provided for in subsection (c), or the total amount of customs duties owed on the materials on importation into the United States, or the total amount of customs duties paid to the USMCA country on the product, and 100 percent during the 8-year period beginning on January 1, 2004 , 75 percent during the 1-year period beginning on January 1, 2012 , 50 percent during the 1-year period beginning on January 1, 2013 , and 25 percent during the 1-year period beginning on January 1, 2014 , or upon the transfer to another bonded smelting or refining warehouse without physical shipment of metal of bond charges representing a quantity of dutiable metal contained in imported metal-bearing materials less wastage provided for in subsection (c) of the plant of initial treatment of such materials provided there is on hand at the warehouse to which the transfer is made sufficient like metal in any form to satisfy the transferred bond charges. For purposes of paragraphs (1), (3), (4), and (5) of subsection (b), due allowances shall be made for wastage of metals other than copper, lead, and zinc, as ascertained from time to time by the Secretary of the Treasury. the total amount of customs duties paid or owed on the materials on importation into the United States, or the total amount of customs duties paid to the USMCA country on the product; and 100 percent of the total amount of customs duties paid or owed on the materials on importation into the United States during the 8-year period beginning on January 1, 2004 , 75 percent of the total amount of customs duties paid or owed on the materials on importation into the United States during the 1-year period beginning on January 1, 2012 , 50 percent of the total amount of customs duties paid or owed on the materials on importation into the United States during the 1-year period beginning on January 1, 2013 , and 25 percent of the total amount of customs duties paid or owed on the materials on importation into the United States during the 1-year period beginning on January 1, 2014 . Two or more smelting or refining warehouses may be included under one general bond and the quantities of each kind of metal subject to duty on hand at all of such warehouses may be aggregated to satisfy the bond obligation. the term “metal-bearing materials” means metal-bearing ores and other metal-bearing materials provided for in chapter 26 of the Harmonized Tariff Schedule of the United States, metal waste and scrap and unwrought metal to be smelted or refined provided for in chapters 71 through 83 of the Harmonized Tariff Schedule of the United States, and metal compounds to be processed for the recovery of their metal content; for the treatment of metal-bearing materials to reduce the metal content thereof to a metallic state in the course of recovering it in forms which if imported would be classifiable in chapters 71 through 83 of the Harmonized Tariff Schedule of the United States as unwrought metal, or in the form of oxides or other compounds which are obtained directly from the treatment of materials provided for in chapter 26 of the Harmonized Tariff Schedule of the United States, and for the treatment of unwrought metal or metal waste and scrap to remove impurities or undesired components; and the term “product of smelting or refining” means metals or metal-bearing materials resulting directly from smelting or refining processes, but does not include metal-bearing ores of chapter 26 of the Harmonized Tariff Schedule of the United States. Labor performed and services rendered pursuant to this section shall be under the supervision of an officer of the customs, to be appointed by the Secretary of the Treasury and at the expense of the manufacturer. The Secretary of the Treasury is authorized to make such rules and regulations as may be necessary to carry out the provisions of this section.