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                                                                   EXHIBIT 10(m)


                               FIRST AMENDMENT TO
                  FOURTH AMENDED AND RESTATED CREDIT AGREEMENT

     THIS FIRST AMENDMENT TO FOURTH AMENDED AND RESTATED CREDIT AGREEMENT (this
"Amendment") dated as of the 17th day of November, 1998, by and among PLAINS
RESOURCES INC., a Delaware corporation (the "Company"), ING (U.S.) CAPITAL
CORPORATION, as Agent ("Agent"), and the Lenders under the Original Agreement
(as defined herein).

                              W I T N E S S E T H:

     WHEREAS,  the Company, Agent and Lenders entered into that certain Fourth
Amended and Restated Credit Agreement dated as of May 22, 1998 (the "Original
Agreement") for the purposes and consideration therein expressed, pursuant to
which Lenders became obligated to make and made loans to the Company as therein
provided; and

     WHEREAS, the Company, Agent and Lenders desire to amend the Original
Agreement for the purposes described herein;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
and agreements contained herein and in the Original Agreement, in consideration
of the loans which may hereafter be made by Lenders to the Company, and for
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto do hereby agree as follows:


                    ARTICLE I. -- Definitions and References

     (S) 1.1.  Terms Defined in the Original Agreement.  Unless the context
otherwise requires or unless otherwise expressly defined herein, the terms
defined in the Original Agreement shall have the same meanings whenever used in
this Amendment.

     (S) 1.2.  Other Defined Terms.  Unless the context otherwise requires, the
following terms when used in this Amendment shall have the meanings assigned to
them in this (S) 1.2.

          "Amendment" means this First Amendment to Fourth Amended and Restated
     Credit Agreement.

          "Amendment Documents" means this Amendment.

          "Credit Agreement" means the Original Agreement as amended hereby.

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                           ARTICLE II. -- Amendments
 
     (S) 2.1.    Definitions.  The definitions of "Subsidiary Guarantor" and
"Unrestricted Subsidiary" set forth in Section 1.01 of the Original Agreement
are hereby amended in their entirety to read as follows:

          "Subsidiary Guarantor" shall mean each of the following Subsidiaries
     of the Company:  Stocker Resources, L.P., Calumet Florida, Inc., Plains
     Illinois Inc., Plains Resources International Inc. and Stocker Resources,
     Inc.

          "Unrestricted Subsidiary" shall mean each of PAAI, the MLP, All
     American Pipeline LP and Plains Marketing LP and each of their respective
     Subsidiaries, whether now existing or hereafter formed or acquired.

     The definitions of  "PMTI" and "PMTI Credit Facility" set forth in Section
1.01 of the Original Agreement are hereby deleted in their entirety.

     The following definition of "Affiliate Agreements" is hereby added to
Section 1.01 of the Original Agreement immediately following the definition of
"Affiliate":

          "Affiliate Agreements" means (i) that certain Crude Oil Marketing
     Agreement dated as of the Offering Closing Date among the Company, Plains
     Illinois Inc., Stocker Resources, L.P., Calumet Florida, Inc. and Plains
     Marketing LP, (ii) that certain Omnibus Agreement dated as of the Offering
     Closing Date among the Company, the MLP, Plains Marketing LP, All American
     Pipeline LP and PAAI, (iii) that certain Contribution, Conveyance and
     Assumption Agreement dated as of the Offering Closing Date among the MLP,
     the Company and certain other parties, and (iv) that certain Underwriting
     Agreement dated as of November 17, 1998 among the Company, the MLP, All
     American Pipeline LP, Plains Marketing LP, PAAI and the underwriters party
     thereto.

     The following definition of "All American Pipeline LP" is hereby added to
Section 1.01 of the Original Agreement immediately following the definition of
"Agent":

          "All American Pipeline LP" means All American Pipeline, L.P., a Texas
     limited partnership, in which, on the Offering Closing Date, the MLP will
     own a 99.999% limited partner interest, and PAAI will own a 0.001% general
     partner interest.

     The following definitions of "MLP" and "MLP Offering Prospectus" are hereby
added to Section 1.01 of the Original Agreement immediately following the
definition of "Maximum Rate":

          "MLP" means Plains All American Pipeline, L.P., a Delaware limited
     partnership, in which PAAI will own, on the Offering Closing Date, a one
     percent (1%) general partner interest and (ii) indirectly, a 55.9% (assumes
     no exercise of underwriters' over-allotment option) limited partner
     interest.

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          "MLP Offering Prospectus" means that certain Prospectus dated November
     17, 1998 regarding the offering by the MLP of common units representing
     limited partner interests in the MLP.

     The following definition of "Offering Closing Date" is hereby added to
Section 1.01 of the Original Agreement immediately following the definition of
"Obligors":

          "Offering Closing Date" means the date of delivery to the
     underwriters, and payment for, the common units representing limited
     partner interests in the MLP, offered pursuant to the initial public
     offering thereof as described in the MLP Offering Prospectus.

     The following definition of "Plains Marketing LP" is hereby added to
Section 1.01 of the Original Agreement immediately following the definition of
"Person":

          "Plains Marketing LP" means Plains Marketing, L.P., a Delaware limited
     partnership, in which, on the Offering Closing Date, the MLP will own a
     98.9899% limited partner interest, and PAAI will own a 1.0101% general
     partner interest.

     (S) 2.2.    PMTI Provisions.  Sections 8.08(j), 8.08(k) and 8.09(e) of the
Original Agreement are hereby deleted in their entirety.  Section 8.10(c) of the
Original Agreement is hereby amended in its entirety to read as follows:

          (c) loans, advances and other extensions of credit made after the date
     hereof by the Company and its Subsidiaries to Subsidiaries of the Company
     in the ordinary course of business, provided that (i) the aggregate amount
     of such loans, advances and other extensions of credit by the Company to
     any one of its Subsidiaries shall not exceed $5,000,000 at any one time
     outstanding and (ii) the aggregate amount of such loans, advances and other
     extensions of credit by the Company to its Subsidiaries taken as a whole
     shall not exceed $5,000,000 at any one time outstanding; in addition to the
     foregoing, so long as no Default shall have occurred and be continuing or
     would exist after giving effect thereto, the Company may make Investments
     without limitation in Stocker Resources, Inc., Stocker Resources, L.P.,
     Calumet Florida Inc. and Plains Illinois Inc.

The proviso in the first sentence of Section 8.19 of the Original Agreement is
hereby deleted in its entirety.  Section 8.29 of the Original Agreement is
hereby deleted in its entirety.  Section 8.33(a) of the Original Agreement is
hereby deleted in its entirety.

     (S) 2.4.    Unrestricted Subsidiaries.  Section 8.35 of the Original
Agreement is hereby amended in its entirety to read as follows:

          8.35  Unrestricted Subsidiaries. Each Unrestricted Subsidiary shall be
     subject to the following:

          (a) No Unrestricted Subsidiary shall be deemed to be a "Subsidiary" of
     the Company for purposes of this Agreement or any other Basic Document, and
     no 

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     Unrestricted Subsidiary shall be subject to or included within the scope of
     any provision herein or in any other Basic Document, including without
     limitation any representation, warranty, covenant or Event of Default
     herein or in any other Basic Document, except as set forth in this Section
     8.35.

          (b) Except as permitted under Section 8.10(e) and (f) and for the
     indemnity undertakings of the Company and its Subsidiaries party thereto
     provided for in the Affiliate Agreements, neither the Company nor any of
     its Subsidiaries shall Guarantee any Indebtedness or other obligation of,
     grant any Lien on any of its Property to secure any Indebtedness or other
     obligation of, make any Investment in, assume or grant an indemnity with
     respect to, or provide any other form of credit support to, any
     Unrestricted Subsidiary, and neither the Company nor any of its
     Subsidiaries shall enter into (i) any management contract or agreement with
     any Unrestricted Subsidiary, except upon the prior written consent of
     Majority Lenders, not to be unreasonably withheld, or (ii) any other
     contract or agreement with any Unrestricted Subsidiary, except in the
     course of ordinary business on terms no less favorable to the Company or
     such Subsidiary, as applicable, than could be obtained in a comparable
     arm's length transaction from an unaffiliated party.

     (S) 2.5.  Consent to MLP-related Transactions.  In connection with the
MLP's proposed offering of common units representing limited partner interests
in itself to the public, as set forth in the MLP Offering Prospectus, copies of
which have been made available to Agent and Lenders:

    (a) Agent and Lenders hereby consent to the Company and its Subsidiaries
     party thereto (i) following the merger of PMTI (as defined in the Original
     Agreement), Plains Terminal & Transfer Corporation, PLX Crude Lines, Inc.
     and PLX Ingleside Inc. with and into the Company, with the Company being
     the surviving entity, selling certain assets held by such merged
     Subsidiaries prior to such merger to Plains Marketing LP, and (ii) entering
     into the Affiliate Agreements, copies of which have been made available to
     Agent and Lenders; and

   (b) Agent and Lenders hereby waive any Default or Event of Default caused by
     any of the foregoing or the consummation of any of the other transactions
     set forth in the MLP Registration Statement.

In connection with the foregoing, for good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, Agent and each Lender
do hereby release and discharge in full PMTI,  Plains Terminal and Transfer
Corporation, PLX Crude Lines Inc. and PLX Ingleside Inc. (collectively, the
"Released Subsidiary Guarantors") and their respective successors and assigns,
from any and all obligations under that certain Amended and Restated Guaranty
dated May 2, 1998 by the Released Subsidiary Guarantors, Plains Resources
International Inc. and Stocker Resources, Inc. in favor of Agent and Lenders.
This is a partial release only and shall not release, discharge or impair any
rights, titles, interests, liens, or powers with respect to any other Subsidiary
Guarantor existing by virtue of such Guaranty or any other Security Documents,
and as to all such other Subsidiary Guarantors, such Guaranty and the other
Security Documents shall remain in full force and effect in accordance with
their respective terms.

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                  ARTICLE III. -- Conditions of Effectiveness

     (S) 3.1.  Effective Date.  This Amendment shall become effective as of the
date first above written when and only when Agent shall have received, at
Agent's office, a counterpart of this Amendment executed and delivered by the
Company, Agent and each Lender.

                 ARTICLE IV. -- Representations and Warranties

     (S) 4.1.  Representations and Warranties of the Company.  In order to
induce Agent and Lenders to enter into this Amendment, the Company represents
and warrants to Agent and Lenders that:

          (a) The representations and warranties contained in Section 7 of the
     Original Agreement, are true and correct at and as of the time of the
     effectiveness hereof, subject to the amendment of certain of the Schedules
     to the Credit Agreement as attached hereto.

          (b) The Company and the Subsidiaries are duly authorized to execute
     and deliver this Amendment and the other Amendment Documents to the extent
     a party thereto, and the Company is and will continue to be duly authorized
     to borrow and perform its obligations under the Credit Agreement.  The
     Company and the Subsidiaries have duly taken all corporate action necessary
     to authorize the execution and delivery of this Amendment and the other
     Amendment Documents, to the extent a party thereto, and to authorize the
     performance of their respective obligations thereunder.

          (c) The execution and delivery by the Company and the Subsidiaries of
     this Amendment and the other Amendment Documents, to the extent a party
     thereto, the performance by the Company and the Subsidiaries of their
     respective obligations hereunder and thereunder, and the consummation of
     the transactions contemplated hereby and thereby, do not and will not
     conflict with any provision of law, statute, rule or regulation or of the
     certificate or articles of incorporation and bylaws of the Company or any
     Subsidiary, or of any material agreement, judgment, license, order or
     permit applicable to or binding upon the Company or any Subsidiary, or
     result in the creation of any lien, charge or encumbrance upon any assets
     or properties of the Company or any Subsidiary, except in favor of Agent
     for the benefit of Lenders.  Except for those which have been duly
     obtained, no consent, approval, authorization or order of any court or
     governmental authority or third party is required in connection with the
     execution and delivery by the Company or any Subsidiary of this Amendment
     or any other Amendment Document, to the extent a party thereto, or to
     consummate the transactions contemplated hereby and thereby.

          (d) When this Amendment and the other Amendment Documents have been
     duly executed and delivered, each of the Basic Documents, as amended by
     this Amendment and the other Amendment Documents, will be a legal and
     binding instrument and agreement of the Company and the Subsidiaries, to
     the extent a party thereto, enforceable in accordance with its terms,
     (subject, as to enforcement of remedies, to 

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     applicable bankruptcy, insolvency and similar laws applicable to creditors'
     rights generally and to general principles of equity).

                          ARTICLE V. -- Miscellaneous

     (S) 5.1.  Ratification of Agreements.  The Original Agreement, as hereby
amended, is hereby ratified and confirmed in all respects.  The Basic Documents,
as they may be amended or affected by this Amendment and/or the other Amendment
Documents, are hereby ratified and confirmed in all respects.  Any reference to
the Credit Agreement in any Basic Document shall be deemed to refer to this
Amendment also.  The execution, delivery and effectiveness of this Amendment and
the other Amendment Documents shall not, except as expressly provided herein or
therein, operate as a waiver of any right, power or remedy of Agent or any
Lender under the Credit Agreement or any other Basic Document nor constitute a
waiver of any provision of the Credit Agreement or any other Basic Document.

     (S) 5.2.  Ratification of Security Documents.  The Company, Agent and
Lenders each acknowledge and agree that any and all indebtedness, liabilities or
obligations arising under or in connection with the Notes are Obligations and is
secured indebtedness under, and is secured by, each and every Security Document
to which the Company is a party.  The Company hereby re-pledges, re-grants and
re-assigns a security interest in and lien on every asset of the Company
described as collateral in any Security Document.

     (S) 5.3.  Survival of Agreements.  All representations, warranties,
covenants and agreements of the Company herein and in the other Amendment
Documents shall survive the execution and delivery of this Amendment and the
other Amendment Documents and the performance hereof and thereof, including
without limitation the making or granting of each Loan, and shall further
survive until all of the Obligations are paid in full.  All statements and
agreements contained in any certificate or instrument delivered by the Company
or any Subsidiary hereunder, under the other Amendment Documents or under the
Credit Agreement to Agent or any Lender shall be deemed to constitute
representations and warranties by, or agreements and covenants of, the Company
under this Amendment and under the Credit Agreement.

     (S) 5.4.  Basic Documents.  This Amendment and each of the other Amendment
Documents is a Basic Document, and all provisions in the Credit Agreement
pertaining to Basic Documents apply hereto and thereto.

     (S) 5.5.  GOVERNING LAW.  THIS AMENDMENT AND THE OTHER AMENDMENT DOCUMENTS
SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF
NEW YORK AND ANY APPLICABLE LAWS OF THE UNITED STATES OF AMERICA IN ALL
RESPECTS, INCLUDING CONSTRUCTION, VALIDITY AND PERFORMANCE.

     (S) 5.6.  Counterparts.  This Amendment and each of the other Amendment
Documents may be separately executed in counterparts and by the different
parties hereto in separate counterparts, each of which when so executed shall be
deemed to constitute one and the same Amendment or Amendment Document, as the
case may be.

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     IN WITNESS WHEREOF, this Amendment is executed as of the date first above
written.

                              PLAINS RESOURCES INC.

                              By:/s/ Phillip D.  Kramer
                                 ----------------------
                                 Phillip D. Kramer
                                 Vice President and Chief Financial Officer


                              ING (U.S.) CAPITAL CORPORATION,
                              as Agent and a Lender

                              By: /s/ Christopher R.  Wagner
                                 ---------------------------
                                 Christopher R. Wagner, Senior Vice President


                              BANKBOSTON, N.A., Lender

                              By:   /s/ Terrence Ronan
                                 ---------------------
                                 Terrence Ronan, Vice President


                              DEN NORSKE BANK ASA, Lender

                              By:   /s/ Byron L.  Cooley
                                 -----------------------
                                 Byron L. Cooley, Senior Vice President

                              By:   /s/ William V.  Moyer
                                 ------------------------
                                 William V. Moyer, First Vice President


                              WELLS FARGO BANK (TEXAS),
                              NATIONAL ASSOCIATION, Lender

                              By:   /s/ Ann M.  Rhoads
                                 ---------------------
                                 Ann M. Rhoads, Vice President


                              CHASE BANK OF TEXAS, N.A., Lender

                              By:   /s/ Russell Johnson
                                 ----------------------
                                 Russell Johnson
                                 Vice President

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                              COMERICA BANK-TEXAS, Lender


                              By:   /s/ Daniel P. Tralmer
                                 -------------------------
                                 Daniel P. Tralmer, Assistant Vice President


                              MEESPIERSON CAPITAL CORP., Lender


                              By:   /s/ Darrell W. Holley
                                 -------------------------
                                 Darrell W. Holley, Senior Vice President

                              By:   /s/ Karel Louman
                                 -------------------
                                 Karel Louman, Managing Director


                              BANK OF SCOTLAND, Lender

                              By:   /s/ Annie Chin Tat
                                 ---------------------
                                 Annie Chin Tat, Senior Vice President


                              U.S. BANK NATIONAL ASSOCIATION, Lender

                              By:   /s/ Monte E. Deckerd
                                 ------------------------
                                 Monte E. Deckerd, Vice President


                              HIBERNIA NATIONAL BANK

                              By:   /s/ Tammy Angelety
                                 ---------------------
                                 Tammy Angelety
                                 Assistant Vice President

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                             CONSENT AND AGREEMENT
                             ---------------------

     Each of the undersigned Subsidiary Guarantors hereby consents to the
provisions of this Amendment and the transactions contemplated herein and hereby
(i) acknowledges and agrees that any and all indebtedness, liabilities or
obligations arising under or in connection with the Notes are Obligations and
are secured indebtedness under, and are secured by, each and every Security
Document to which it is a party, (ii) re-pledges, re-grants and re-assigns a
security interest in and lien on all of its assets described as collateral in
any Security Document, (iii) ratifies and confirms its Amended and Restated
Guaranty dated May 22, 1998 made by it for the benefit of Agent and Lenders, and
(iv) expressly acknowledges and agrees that such Subsidiary Guarantor guarantees
all indebtedness, liabilities and obligations arising under or in connection
with the Notes pursuant to the terms of such Amended and Restated Guaranty, and
agrees that its obligations and covenants thereunder are unimpaired hereby and
shall remain in full force and effect.

                         PLAINS RESOURCES INTERNATIONAL INC.
                         STOCKER RESOURCES, INC.
                         CALUMET FLORIDA, INC.
                         PLAINS ILLINOIS INC.


                         By:   /s/ Phillip D.  Kramer
                            -------------------------
                            Phillip D. Kramer
                            Vice President and Chief Financial Officer


                         STOCKER RESOURCES, L.P.

                         By:  Stocker Resources, Inc.,
                               its General Partner


                              By:   /s/ Phillip D.  Kramer
                                 -------------------------
                                 Phillip D. Kramer
                                 Vice President and Chief Financial Officer

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