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                                                                   EXHIBIT 10(i)

                               FIRST AMENDMENT TO
                  THIRD AMENDED AND RESTATED CREDIT AGREEMENT

         THIS FIRST AMENDMENT TO THIRD AMENDED AND RESTATED CREDIT AGREEMENT
(this "Amendment") dated as of the 16th day of December, 1996, by and among
PLAINS RESOURCES INC., a Delaware corporation (the "Company"), ING (U.S.)
CAPITAL CORPORATION, f/k/a Internationale Nederlanden (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
Third Amended and Restated Credit Agreement dated as of April 11, 1996 (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 to (i) set forth certain agreements relating to an indemnity or other
credit support which ING (U.S.) Capital Corporation may provide on behalf of
Borrower in connection with Hedging Transactions, and (ii) incorporate
amendments to the Bank of Boston/ING Capital Facility;

         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

         Section  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.

         Section  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 Section  1.2.

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

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





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                           ARTICLE II. -- Amendments

         Section  2.1.    Definitions.  The definitions of "Applicable Margin",
"Bank of Boston/ING Capital Facility" and "Hedging Agreement" set forth in
Section 1.01 of the Original Agreement are hereby amended in their entirety to
read as follows:

                          "Applicable Margin" shall mean (i) with respect to
         Base Rate Loans zero percent (0%) per annum and (ii) with respect to
         Eurodollar Loans, one and three-eighths percent (1.375%) per annum.
        
                          "Bank of Boston/ING Capital Facility" shall mean,
         collectively, two uncommitted secured demand transactional line of
         credit facilities, in an aggregate amount not to exceed $90,000,000,
         dated August 23, 1995, as amended as of November 20, 1996, among The
         First National Bank of Boston, individually and as agent, ING (U.S.)
         Capital Corporation, the other lenders named therein, and (i) Plains
         Marketing, and (ii) PMCT, together with the security documents and
         other documents and agreements executed in connection with each such
         facility.
        
                          "Hedging Agreement" shall mean (i) any currency rate
         swap, rate cap, rate floor, rate collar, exchange transaction, forward
         rate agreement, or other exchange or rate protection agreements or any
         option with respect to any such transaction now existing or hereafter
         entered into between any Obligor and Agent, AIG Trading Corporation,
         or any Lender, or (ii) any swap agreement, cap, floor, collar,
         exchange transaction, forward agreement, or other exchange or
         protection agreements relating to crude oil, natural gas or other
         hydrocarbons, or any option with respect to any such transaction now
         existing or hereafter entered into between any Obligor and Agent, AIG
         Trading Corporation, or any Lender.
        
         Section  2.2     Hedging Agreement Indemnity.  Article 2 of the
Original Agreement is hereby amended by adding a new Section 2.10 to read as
follows:

                 2.10.    Hedging Agreement Indemnity.  From time to time ING
         (U.S.) Capital Corporation ("ING Capital") may provide an indemnity or
         other credit support on behalf of Obligors to AIG Trading Corporation,
         whereby ING Capital agrees to pay the obligations of such Obligor
         arising from time to time under a Hedging Agreement (a "Hedging
         Agreement Indemnity").  In consideration thereof, the Company hereby
         promises and agrees to pay to ING Capital each amount which ING
         Capital is called upon to pay on behalf of or for the benefit of such
         Obligor under a Hedging Agreement Indemnity.  The Company shall pay
         each such amount, immediately upon demand, in legal tender of the
         United States in same day funds.  Such promise and agreement of the
         Company is irrevocable and unconditional.  ING Capital is authorized
         and instructed to pay all demands for payment under any such Hedging
         Agreement Indemnity after exercising reasonable care to determine
         whether such demand or the amount thereof is correct.  The Company
         hereby promises to pay to ING Capital, on demand, interest at the
         Post-Default Rate on any amount payable by the Company





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         under this section from the date such amounts become due until they
         are paid.  The Company may enter into a separate Reimbursement
         Agreement governing such promise and agreement of the Company to pay
         to ING Capital each amount which ING Capital is called upon to pay on
         behalf of or for the benefit of such Obligor under a Hedging Agreement
         Indemnity.  Notwithstanding the existence of any such separate
         Reimbursement Agreement, the obligation of the Company described in
         this section shall be an "Obligation" arising under this Agreement and
         shall be secured by and entitled to the benefit of all Guaranties and
         Security Documents, whether or not the Security Documents specifically
         describe such separate Reimbursement Agreement or the obligations of
         the Company under this section.  Each payment under a Hedging
         Agreement Indemnity (whether in response to a demand for payment or
         otherwise) shall constitute a loan by ING Capital and shall be secured
         by and entitled to all benefits under the Security Documents.

         Section  2.3.    Indebtedness.  Section 8.09(e) is hereby amended in
its entirety to read as follows:

                 (e)      (i) Indebtedness of Plains Marketing, PMCT and their
         Wholly-Owned Subsidiaries under the Bank of Boston/ING Capital
         Facility, and the guaranty by the Company of such Indebtedness
         (together with reimbursement obligations of the Company in connection
         with the Support Letter of Credit), (ii) the unsecured guaranty by
         PMCT of the indebtedness of the Company under the Senior Subordinated
         Indenture and the Senior Subordinated Notes, (iii) other Indebtedness
         of Plains Marketing, PMCT and their Wholly-Owned Subsidiaries arising
         in the ordinary course of their businesses under crude oil purchase or
         sale agreements, crude oil future, forward or similar contracts, or
         letters of credit supporting such obligations, and the unsecured
         guaranty by the Company of such other Indebtedness, and (iv) the
         unsecured guaranty by the Company of indebtedness of Plains Marketing,
         PMCT and their Wholly-Owned Subsidiaries arising in the ordinary
         course of their businesses under crude oil purchase or sale
         agreements, crude oil future, forward or similar contracts, or letters
         of credit supporting such obligations; provided, the aggregate
         outstanding amount of such Indebtedness under the preceding clauses
         (iii) and (iv) shall not at any time exceed (A) $125,000,000 minus (B)
         the outstanding Indebtedness under the Bank of Boston/ING Capital
         Facility.

                         ARTICLE III. -- Miscellaneous


         Section  3.1.    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 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.

         Section  3.2.    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





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or affected by this Amendment 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 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.

         Section  3.3.    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.

         Section  3.4.    Survival of Agreements.  All representations,
warranties, covenants and agreements of the Company herein shall survive the
execution and delivery of this Amendment 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 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.

         Section  3.5.    Basic Document.  This Amendment is a Basic Document,
and all provisions in the Credit Agreement pertaining to Basic Documents apply
hereto and thereto.

         Section  3.6.    GOVERNING LAW.  THIS AMENDMENT 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.

         Section  3.7.    Counterparts.  This Amendment 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.

   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
                                        




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                                       ING (U.S.) CAPITAL CORPORATION,
                                       f/k/a Internationale Nederlanden (U.S.) 
                                       Capital Corporation, individually as a 
                                       Lender and as Agent
                                       
                                       
                                       By:        /s/  Robi Artman-Hodge       
                                          --------------------------------------
                                           Robi Artman-Hodge, Managing Director
                                       
                                       
                                       THE FIRST NATIONAL BANK OF BOSTON, 
                                       Lender
                                       
                                       
                                       By:        /s/ George W. Passela        
                                          --------------------------------------
                                           George W. Passela, Managing Director
                                       
                                       
                                       DEN NORSKE BANK AS, Lender
                                       
                                       
                                       
                                       By:        /s/ Byron L. Cooley          
                                          --------------------------------------
                                           Byron L. Cooley,Senior Vice President
                                       
                                       
                                       By:        /s/ Morten Bjornsen        
                                          --------------------------------------
                                           Morten Bjornsen, Senior Vice 
                                           President
                                       
                                       
                                       WELLS FARGO BANK (TEXAS)
                                       NATIONAL ASSOCIATION
                                       (f/k/a First Interstate Bank of Texas, 
                                       N.A.), Lender
                                       
                                       
                                       By:        /s/ Ann M. Rhoads            
                                          --------------------------------------
                                           Ann M. Rhoads, Vice President
                                       
                                       

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                                       TEXAS COMMERCE BANK NATIONAL 
                                       ASSOCIATION, Lender
                                       
                                       
                                       By:        /s/ Scott H. Richardson      
                                          --------------------------------------
                                           Scott H. Richardson, 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 April 11, 1996 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.  Each of the
undersigned hereby further agrees that any obligation of the Company arising
pursuant to Section 2.10 of the Credit Agreement shall constitute "Obligations"
under the Guaranty.



                                      PLAINS MARKETING & TRANSPORTATION INC.
                                      
                                      
                                      By:       /s/ Phillip D. Kramer          
                                         --------------------------------------
                                           Phillip D. Kramer, Vice President
                                      
                                      
                                      PLAINS RESOURCES INTERNATIONAL INC.
                                      
                                      
                                      By:       /s/ Phillip D. Kramer          
                                         --------------------------------------
                                           Phillip D. Kramer, Vice President
                                      
                                      
                                      PLAINS TERMINAL & TRANSFER CORPORATION
                                      
                                      
                                      By:       /s/ Phillip D. Kramer          
                                         --------------------------------------
                                           Phillip D. Kramer, Vice President
                                      
                                      
                                      PLX CRUDE LINES INC.
                                      
                                      
                                      By:       /s/ Phillip D. Kramer          
                                         --------------------------------------
                                           Phillip D. Kramer, Vice President
                                      
                                      
                                      


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                                    STOCKER RESOURCES, INC.
                                    
                                    
                                    By:       /s/ Phillip D. Kramer            
                                       ----------------------------------------
                                         Phillip D. Kramer, Vice President
                                    
                                    
                                    PLX INGLESIDE INC.
                                    
                                    
                                    By:       /s/ Phillip D. Kramer            
                                       ----------------------------------------
                                         Phillip D. Kramer, Vice President
                                    
                                    
                                    STOCKER RESOURCES, L.P.
                                    
                                    By:     Stocker Resources, Inc.,
                                             its General Partner
                                    
                                    
                                            By:       /s/ Phillip D. Kramer    
                                               --------------------------------
                                                 Phillip D. Kramer, Vice 
                                                 President
                                    
                                    
                                    CALUMET FLORIDA, INC.
                                    
                                    
                                    By:       /s/ Phillip D. Kramer            
                                       ----------------------------------------
                                         Phillip D. Kramer, Vice President
                                    
                                    
                                    PLAINS ILLINOIS INC.
                                    
                                    
                                    By:       /s/ Phillip D. Kramer            
                                       ----------------------------------------
                                         Phillip D. Kramer, Vice President
                                    




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