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                                                                    EXHIBIT 10


                       Champion International Corporation
                               One Champion Plaza
                               Stamford, CT 06921



                                                             September 30, 1998


 Mr. Burton G. MacArthur, Jr.
 1 Surf Road
 Westport, CT  06880

                                      Re:  Special Provisions Relating to
                                           Your Termination of Employment

Dear Twig:

    This letter sets forth certain special provisions relating to your
termination of employment at the close of business today.

                                       I.

    Reference is made to the Non-Statutory Stock Option Agreements between you
and Champion International Corporation (the "Company") dated March 19, 1997 (the
1997 Option Agreement) and April 15, 1998 (the "1998 Option Agreement").

    The 1998 Option Agreement is hereby amended to vest as of the date hereof
the stock option granted thereunder. The date on which such stock option becomes
exercisable shall remain April 15, 1999.

    Each of the 1997 Option Agreement and 1998 Option Agreement (each an Option
Agreement) is hereby amended to include the following provisions, provided that
the stock option granted under the 1998 Option Agreement may not be exercised
before April 15, 1999:

    (1)  You shall have the right, at any time until the expiration date of the
         stock option granted under such Option Agreement, to exercise the
         unexercised portion thereof.

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    (2)  If you shall die while the stock option granted under such Option
         Agreement is exercisable pursuant to clause (1) immediately above, the
         person or persons to whom such stock option shall have been transferred
         by will or the laws of descent and distribution (including your estate
         during the period of administration) shall have the right, at any time
         until the expiration date of such stock option, to exercise the
         unexercised portion thereof.

              This letter  agreement  constitutes  an  amendment  of each of the
       Option  Agreements.  Any  provisions  of the Option  Agreements  that are
       inconsistent  with the  provisions  of this letter  agreement  are hereby
       superseded  by the  provisions of this letter  agreement,  but the Option
       Agreements  in all other  respects  shall remain in full force and effect
       without change.


                                       II.

    The Compensation and Stock Option Committee (the "Committee") of the Board
of Directors of the Company, at its meeting in January 1999, shall determine the
amount of annual bonus, if any, that would have been paid to you for 1998 if you
had remained in the Company's employment for all of 1998. In making this
determination, the Committee (i) shall apply the performance criteria that it
has adopted for the 1998 annual bonus for executive officers and (ii) shall
assume that you served as an Executive Vice President for one-third of the year
and as a Senior Vice President for two-thirds of the year. If the Committee
determines that such an annual bonus would have been paid to you, then the
Company shall pay to you an amount equal to 75% of such annual bonus.


                                      III.

    In consideration of the special benefits provided by the Company set forth
above, you agree that, without the Company's prior written consent, you shall
not compete, directly or indirectly, with the Company or any of its subsidiaries
or affiliates, including without limitation by entering into employment or
consulting arrangements with any entity that engages in such competition, for a
period of two years from the date hereof. This provision shall supersede
paragraph 3(e) of the Agreement dated October 18, 1990 between the Company and
you, as amended (the "Severance Agreement"), but the Severance Agreement in all
other respects shall remain in full force and effect without change.
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                                       IV.

    Please confirm your consent to the provisions of this letter agreement by
countersigning and retaining one copy and by countersigning the other copy and
returning it, whereupon it will constitute a binding agreement between you and
the Company.


                       CHAMPION INTERNATIONAL CORPORATION



                                        By /s/ Richard E. Olson
                                           -------------------------------------
                                           Chairman and Chief Executive Officer

ATTEST:


 /s/ Lawrence A. Fox
-------------------------------
Vice President and Secretary

                                                    CONFIRMED AND AGREED TO:

                                                    /s/ Burton G. MacArthur, Jr.
                                                    ----------------------------
                                                    Burton G. MacArthur, Jr.