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                                                                   EXHIBIT 10.1


                 FIRST AMENDMENT TO SECURED TERM LOAN AGREEMENT

                  This First Amendment to Secured Term Loan Agreement dated as
of May 9, 2003 ("First Amendment"), is by and among PLAINS RESOURCES INC., a
Delaware corporation (the "Borrower"), BANK OF MONTREAL, acting through certain
of its U.S. branches or agencies, as administrative agent for the Lenders (in
such capacity, the "Administrative Agent"), BANK ONE, NA, as syndication agent
(in such capacity, the "Syndication Agent"), WELLS FARGO BANK TEXAS, NA, as
collateral agent (in such capacity, the "Collateral Agent") and documentation
agent (in such capacity, the "Documentation Agent", and together with the
Administrative Agent, the Syndication Agent, and the Collateral Agent,
collectively, the "Agents") and the various commercial lending institutions as
are or may become parties to the Loan Agreement (collectively, the "Lenders").
This First Amendment amends that certain Secured Term Loan Agreement dated as of
December 6 2002 (the "Loan Agreement"), by and among the Borrower, the Agents
and the Lenders.

                              W I T N E S S E T H:

         WHEREAS, pursuant to a certificate of conversion filed with the
Secretary of State of Delaware, effective as of May 2, 2003, Plains Holdings
LLC, a Delaware limited liability company and an indirect subsidiary of the
Borrower (the "LLC"), was converted to Plains Holdings II Inc., a Delaware
corporation;

         WHEREAS, the LLC is party to several Loan Documents described in the
Loan Agreement; and

         WHEREAS, in order to reflect the change in the LLC's name and corporate
status, the Lenders, the Borrower and the other parties to the Loan Agreement
desire to amend the Loan Agreement in certain respects as specifically set forth
herein:

         NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration received by each party hereto, and each intending to be
legally bound hereby, the parties hereto agree as follows:

         1. Amendments to Loan Agreement. All references in the Loan Agreement
to the term "Plains Holdings LLC" are hereby amended to read, in each instance,
"Plains Holdings II".

         2. Amendment to Section 1.1 of the Loan Agreement. The definition of
"Plains Holdings LLC" is hereby deleted from Section 1.1 of the Loan Agreement
and replaced in its entirety by the following:

              "Plains Holdings II" means Plains Holdings II Inc., a Delaware
              corporation and a wholly-owned Subsidiary of Plains Holdings Inc.

         3. Defined Terms. Unless otherwise defined herein, terms used herein
that are defined in the Loan Agreement shall have the same meanings herein as in
the Loan Agreement.


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         4. Reaffirmation of Loan Agreement. This First Amendment shall be
deemed to be an amendment to the Loan Agreement, and the Loan Agreement, as
amended hereby, is hereby ratified, approved and confirmed in each and every
respect. All references to the Loan Agreement herein and in any other Loan
Document shall hereafter be deemed to refer to the Loan Agreement as amended
hereby.

         5. Governing Law; Entire Agreement, etc. THIS FIRST AMENDMENT SHALL BE
DEEMED TO BE A CONTRACT MADE UNDER AND GOVERNED BY THE INTERNAL LAWS OF THE
STATE OF TEXAS. The Loan Agreement, as hereby amended, the Notes and the other
Loan Documents constitute the entire understanding among the parties hereto with
respect to the subject matter hereof and supersede any prior agreements, written
or oral, with respect thereto.

         6. Severability. Any provision of this First Amendment which is
prohibited or unenforceable in any jurisdiction shall, as to such provision and
such jurisdiction, be ineffective to the extent of such prohibition or
unenforceability without invalidating the remaining provisions of this First
Amendment affecting the validity or enforceability of such provision in any
other jurisdiction.

         7. Execution in Counterparts, Effectiveness, etc. This First Amendment
may be executed by the parties hereto in several counterparts, each of which
shall be deemed to be an original and all of which shall constitute together but
one and the same agreement. This First Amendment shall become effective when
counterparts hereof executed on behalf of the Borrower, the Administrative Agent
and each Lender (or notice thereof satisfactory to the Administrative Agent)
shall have been received by the Administrative Agent and notice thereof shall
have been given by the Administrative Agent to the Borrower and each Lender.

         8. Section Captions. The various headings of this First Amendment are
inserted for convenience only and shall not affect the meaning or interpretation
of this First Amendment or any provisions hereof.

         9. Successors and Assigns. This First Amendment shall be binding upon
and shall inure to the benefit of the parties hereto and their respective
successors and assigns.

         THE LOAN AGREEMENT, AS HEREBY AMENDED, TOGETHER WITH THE OTHER LOAN
DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS
OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.


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         IN WITNESS WHEREOF, the parties hereto have caused this First Amendment
to be duly executed and delivered by its officers thereunto duly authorized as
of the date first above written.


                                        PLAINS RESOURCES INC.,
                                        as Borrower



                                        By:   /s/ John Raymond
                                              ---------------------------------
                                        Name:  John Raymond
                                              ---------------------------------
                                        Title: CEO & President
                                              ---------------------------------

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                                        BANK OF MONTREAL, acting through its
                                        U.S. branches and agencies, including
                                        initially its Chicago, Illinois branch,
                                        as Administrative Agent



                                        By:   /s/ Joseph A. Bliss
                                              ---------------------------------
                                        Name:  Joseph A. Bliss
                                              ---------------------------------
                                        Title: Vice President
                                              ---------------------------------

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                                        BANK OF MONTREAL, as a Lender



                                        By:   /s/ James V. Ducote
                                              ---------------------------------
                                        Name:  James V. Ducote
                                              ---------------------------------
                                        Title: Director
                                              ---------------------------------

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                                        BANK ONE, NA (MAIN OFFICE CHICAGO),
                                        as Syndication Agent and a Lender



                                        By: /s/ Charles Kingswell-Smith
                                              ---------------------------------
                                        Name: Charles Kingswell-Smith
                                              ---------------------------------
                                        Title:  Director
                                              ---------------------------------

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                                        WELLS FARGO BANK TEXAS, NA, as
                                        Collateral Agent, Documentation Agent
                                        and a Lender



                                        By: /s/ Paul A. Squires
                                              ---------------------------------
                                        Name: Paul A. Squires
                                              ---------------------------------
                                        Title:  Vice President
                                              ---------------------------------