EXHIBIT 10.40

                             TERMINATION AGREEMENT
                             ---------------------

     TERMINATION AGREEMENT, dated as of October 1, 1997 (this "Agreement"),
among TRIZEC HAHN CORPORATION, an Ontario corporation (the "Purchaser"), 1096153
ONTARIO LIMITED, an Ontario corporation ("1096153"), CLARK USA, INC., a Delaware
corporation (the "Company"), TIGER MANAGEMENT CORPORATION, a Delaware
corporation ("Tiger") and PAUL D. MELNUK ("Melnuk").

     WHEREAS, (i) the Purchaser (as successor to The Horsham Corporation),
1096153, the Company and Tiger are parties to a Stock Purchase Agreement, dated
as of February 27, 1995 (the "1995 Stock Purchase Agreement"), and (ii) the
Company, Tiger, 1096153 and Melnuk are parties to a Registration Rights
Agreement, dated as of February 27, 1995 (the "1995 Registration Rights
Agreement"); and

     WHEREAS, the Company, The Jaguar Fund, N.V. ("Jaguar"), Puma (a limited
partnership) ("Puma"), Tiger (a limited partnership) (together with Jaguar and
Puma, the "Sellers"), Tiger and the Purchaser have entered into a Class A Common
Stock Reclassification Agreement, dated as of September 19, 1997, pursuant to
which, among other things, the Sellers, Tiger and the Company have agreed to
terminate the 1995 Stock Purchase Agreement (other than Sections 4.9 and 7.1(a)
thereof) and the 1995 Registration Rights Agreement;

     NOW, THEREFORE, in consideration of the premises and the mutual agreements
and covenants hereinafter set forth, the Company and the Purchasers hereby agree
as follows:

     1.  Termination of 1995 Stock Purchase Agreement and 1995 Registration
Rights Agreement.  (a)  The 1995 Stock Purchase Agreement and the 1995
Registration Rights Agreement are hereby terminated.

     (b) Notwithstanding the foregoing, Sections 4.9 and 7.1(a) of the 1995
Stock Purchase Agreement shall not be terminated hereby and shall continue in
full force and effect in accordance with their terms.

     2.  Further Action.  Each of the parties hereto shall use all reasonable
efforts to take, or cause to be taken, all appropriate action, do or cause to be
done all things necessary, proper or advisable under applicable law, and execute
and deliver such documents and other papers, as may be required to make
effective the provisions of this Agreement.

     3.  Headings.  The descriptive headings contained in this Agreement are for
convenience of reference only and shall not affect in any way the meaning or
interpretation of this Agreement.

 
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     4.  Governing Law.  This Agreement shall be governed by the laws of the
State of New York.

     5.  Counterparts.  This Agreement may be executed in one or more
counterparts (including by facsimile signature), and by the different parties
hereto in separate counterparts, each of which when executed shall be deemed to
be an original but all of which taken together shall constitute one and the same
agreement.

 
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     IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed as of the date first written above by their respective officers
thereunto duly authorized.


                                  TRIZEC HAHN CORPORATION


                                  By: ________________________________
                                     Name:
                                     Title:


                                  By: ________________________________
                                     Name:
                                     Title:


                                  1096153 ONTARIO LIMITED


                                  By: ________________________________
                                     Name:
                                     Title:


                                  CLARK USA, INC.


                                  By: ________________________________
                                     Name:
                                     Title:


                                  TIGER MANAGEMENT CORPORATION


                                  By: ________________________________
                                     Name:
                                     Title:

 
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                                  ___________________________________
                                    Paul D. Melnuk