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                                                                   Exhibit 10.13

                      AMENDMENT TO ALUMINA SUPPLY AGREEMENT

        This Amendment to Alumina Supply Agreement (this "Amendment"), dated as
of October 23, 2000, between Glencore Ltd., a Swiss corporation (the "Seller"),
and Northwest Aluminum Company, an Oregon corporation (the "Buyer," and
collectively with the Seller, the "Parties"). Capitalized terms not otherwise
defined herein shall have the meaning ascribed to them in the Alumina Supply
Agreement dated as of October 15, 1999 between the Parties (the "Alumina
Agreement").

                                   WITNESSETH

        WHEREAS, the Parties entered in to the Alumina Agreement; and

        WHEREAS, the Parties now desire to amend the Alumina Agreement as set
forth in this Amendment.

        NOW, THEREFORE, in consideration of the foregoing and the mutual
covenants and agreements herein contained, and intending to be legally bound
hereby, the Parties do hereby agree as follows:

                                   ARTICLE I.
                              DEFINITIONS AMENDMENT

        1.1     The definition in Section 1.1 of the Alumina Agreement of the
term "LME Price" is hereby amended and restated to read in its entirety as
follows:

                "LME Price" means the London Metal Exchange 3-month price in
                U.S. dollars per MT of 99.7% aluminum ingot as published by
                Reuters on Page MTLE and subsequently published in Metal
                Bulletin averaged over the applicable calendar quarter. In the
                event that LME prices are no longer reported or Metal Bulletin
                discontinues publication and such prices are not longer
                available, the parties will meet and agree upon a comparable
                mechanism to determine the LME Price.

                                   ARTICLE II.
                               QUANTITY AMENDMENT

        2.1     Section 2.2 of the Alumina Agreement is hereby amended and
restated to read in its entirety as follows:

                Seller agrees to sell and Buyer agrees to purchase a total of
                718,979,804 MT of Alumina for The Dalles, commencing November 1,
                1999 and continuing until the quantity specified has been
                delivered under the following estimated schedule:


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                November--December, 1999                        27,000 MT
                January--December, 2000                    131,979,804 MT
                January--December, 2001                         80,000 MT
                January--December, 2002                        160,000 MT
                January--December, 2003                        160,000 MT
                January--December, 2004                        160,000 MT

                The amount of any individual shipment and any annual quantity is
                subject to a tolerance of plus or minus five percent for
                shipping purposes.

                In January 2004 the parties shall negotiate in good faith the
                possible extension of the Alumina Agreement for the supply of
                Alumina in calendar years 2005 and 2006.

                                  ARTICLE III.
                               GENERAL PROVISIONS

        3.1     Cancellation Fee. In consideration for the reduction pursuant to
this Amendment in the quantity of Alumina required to be purchased by the Buyer
in calendar year 2000 and calendar year 2001, the Buyer agrees to pay each
calendar quarter to the Seller (beginning with the fourth calendar quarter of
2000) a cancellation fee of $20 per each MT of reduction in the Buyer's original
commitment for such quarter under the Alumina Agreement, which fee shall be
added to the amount invoiced by the Seller to the Buyer for deliveries during
such calendar quarter.

        3.2     Ratification of Alumina Agreement. The amendments set forth
herein are limited precisely as written and shall not be deemed to be a consent
or waiver to, or modification of, any other term or condition set forth in the
Alumina Agreement. Except as expressly amended hereby, all the terms and
conditions of the Alumina Agreement shall continue in full force and effect and,
as amended hereby, the Alumina Agreement is ratified and confirmed in all
respects.

        3.3     Governing Law. This Amendment shall be governed by and construed
in accordance with the laws of the State of New York, excluding those relating
to choice or conflicts of laws and excluding the United Nations Convention for
the International Sale of Goods.

        3.4     Assignment. This Amendment is binding upon Parties and their
respective successors and assigns. No Party may assign this Amendment or its
rights or obligations hereunder without the prior written consent of the other
Party (which consent shall not be unreasonably withheld) and any purported
assignment without such express written consent shall be null and void.


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        3.5     Counterparts. This Amendment may be executed in any number of
counterparts, each of which when so executed shall be deemed to be an original
and all of which taken together shall constitute one and the same agreement.
Delivery of an executed counterpart of a signature page to this Amendment by
facsimile shall be effective as delivery of a manually executed counterpart of
this Amendment.

        IN WITNESS WHEREOF, the Parties have caused their duly authorized
representatives to execute this Amendment to Alumina Supply Agreement.

                                            GLENCORE LTD.

                                            By:    /s/ ANDREW BENTLEY
                                                 -------------------------------
                                                   Name: Andrew Bentley
                                                   Title:


                                            NORTHWEST ALUMINUM COMPANY

                                            By:    /s/ BRETT WILCOX
                                                 -------------------------------
                                                   Name: Brett Wilcox
                                                   Title:  President


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