<PAGE>
                                                                   EXHIBIT 4.1.5

                               Second Amendment to
                                Third Amended and
                            Restated Credit Agreement




                                  June 6, 2002


Inland Production Company
410  17th Street, Suite 700
Denver, Colorado  80202

Gentlemen:

         This Second Amendment to the Third Amended and Restated Credit
Agreement, as amended(the "Amendment") will serve to set forth the amended terms
of the financing transaction by and between INLAND PRODUCTION COMPANY, a Texas
corporation ("Borrower"), FORTIS CAPITAL CORP., a Connecticut corporation as
Agent ("Agent") and as a Lender, and the other Lenders.

         WHEREAS, Borrower, Agent and the Lenders entered into the Third Amended
and Restated Credit Agreement, dated as of November 30, 2001 (the "Credit
Agreement"); and

         WHEREAS, the Borrower has requested that the Lenders make certain
amendments to the Credit Agreement, and the Lenders are willing to do so subject
to the terms and conditions set forth herein;

         NOW, THEREFORE, in consideration of the premises herein contained and
other good and valuable consideration, the sufficiency of which is hereby
acknowledged, the parties hereto, intending to be legally bound, agree as
follows:

         1.       DEFINED TERMS.  All capitalized terms used but not otherwise
defined in this Amendment shall have the meaning ascribed to them in the Credit
Agreement. Unless otherwise specified, all section references herein refer to
sections of the Credit Agreement.

         2.       AMENDMENTS TO CREDIT AGREEMENT.  The Credit Agreement is
hereby amended as follows:

                  2.1   SECTION 1.1. DEFINITIONS.

                        1. The definition of "Eurodollar Margin" is amended to
                  read as follows:

                      " Eurodollar Margin means the following rate per annum as
                  applicable based on the Senior Debt to EBITDA Ratio in effect
                  from time to time:

<TABLE>
<CAPTION>
                        Senior Debt to
                        EBITDA Ratio                                Eurodollar Margin
                        --------------                              -----------------
                        <S>                                         <C>
                        Greater than 4.00
                        to 1.00                                     3.75%

                        Less than or equal to 4.00 to
                        1.00 but greater than
                        or equal to 3.00 to 1.00                    2.75%
</TABLE>



<PAGE>


<TABLE>
<CAPTION>
                        Senior Debt to
                        EBITDA Ratio                                Eurodollar Margin
                        --------------                              -----------------
                        <S>                                         <C>

                        Less than 3.00 to
                        1.00                                        2.25%
</TABLE>


                        with each change in the Eurodollar Margin resulting from
                  a change in the Senior Debt to EBITDA Ratio taking effect at
                  the time of such change. "

                  2.2   SECTION 7.13. DEBT TO EBITDA RATIO.

                        (a)      Section 7.13 is amended to read as follows:

                        "Section 7.13. Debt to EBITDA Ratio. At the end of
                  any Fiscal Quarter, beginning with the Fiscal Quarter ending
                  September 30, 2001, the ratio of (i) Parent's Consolidated
                  Senior Debt to (ii) Parent's EBITDA, for the four-Fiscal
                  Quarter period ending with such Fiscal Quarter will be equal
                  to or less than (a) 4.75 to 1.00 for the Fiscal Quarter ending
                  June 30, 2002, (b) 4.35 to 1.00 for the Fiscal Quarter ending
                  September 30, 2002, and (c) 3.75 to 1.00 for any Fiscal
                  Quarter ending thereafter."

         3.       WAIVERS AND CONSENTS.  The Lenders hereby agree, approve and
consent as follows:

                  3 1   Section 7.13.  Debt to EBITDA Ratio.  The Agent and the
                        Lenders hereby waive compliance with Section 7.13 of the
                        Credit Agreement for the period January 1, 2002 through
                        March 31, 2002.

         4.       EFFECTIVENESS OF AMENDMENT.  This Amendment shall be effective
as of May 31, 2002 upon receipt by Agent of:

                  (a)   Receipt by the Agent, on behalf of the Lenders, of an
amendment fee equal to 0.10% of the Borrowing Base;

                  (b)   A Consent and Agreement executed by Inland Resources
Inc. as guarantor, and

                  (c)   A Compliance Certificate executed by Borrower.

         5.       RATIFICATIONS, REPRESENTATIONS AND WARRANTIES.

                  (a)   The terms and provisions set forth in this Amendment
shall modify and supersede all inconsistent terms and provisions set forth in
the Credit Agreement and, except as expressly modified and superseded by this
Amendment, the terms and provisions of the Credit Agreement are ratified and
confirmed and shall continue in full force and effect. The Borrower and Lenders
agree that the Credit Agreement and the Loan Documents, as amended hereby, shall
continue to be legal, valid, binding and enforceable in accordance with their
respective terms.

                  (b)   In order to induce Lenders to enter into this Amendment,
each of Borrower and Parent represents and warrants to Lenders that:

                        (i)    The representations and warranties contained in
                  Article V of the Credit Agreement are true and correct at and
                  as of the time of the effectiveness hereof.

                        (ii)   Each Restricted Person is duly authorized to
                  execute and deliver each Loan Document to the extent a party
                  thereto and Borrower is and will continue to be duly
                  authorized to borrow and to perform its obligations under the
                  Credit Agreement as amended hereby. Each Restricted Person has
                  duly taken all action necessary to authorize the execution and
                  delivery of each Loan Document to which it is a party and to
                  authorize the performance of the obligations of each
                  Restricted Person thereunder.


<PAGE>


         6.       BENEFITS. This Amendment shall be binding upon and inure to
the benefit of the Lenders and Borrower, and their respective successors and
assigns; provided, however, that Borrower may not, without the prior written
consent of the Lenders, assign any rights, powers, duties or obligations under
this Amendment, the Credit Agreement or any of the other Loan Documents.

         7.       CONSTRUCTION.  This Amendment shall be governed by and
construed in accordance with the laws of the State of New York.

         8.       INVALID PROVISIONS. If any provision of this Amendment is held
to be illegal, invalid or unenforceable under present or future laws, such
provision shall be fully severable and the remaining provisions of this
Amendment shall remain in full force and effect and shall not be affected by the
illegal, invalid or unenforceable provision or by its severance.

         9.       ENTIRE AGREEMENT.  The Credit Agreement, as amended by this
Amendment, contains the entire agreement among the parties regarding the subject
matter hereof and supersedes all prior written and oral agreements and
understandings among the parties hereto regarding same.

         10.      REFERENCE TO CREDIT AGREEMENT. The Credit Agreement and any
and all other agreements, documents or instruments now or hereafter executed and
delivered pursuant to the terms hereof or pursuant to the terms of the Credit
Agreement, as amended hereby, are hereby amended so that any reference in the
Credit Agreement to the Credit Agreement shall mean a reference to the Credit
Agreement as amended hereby.

         11.      COUNTERPARTS.  This Amendment may be separately executed in
any number of counterparts, each of which shall be an original, but all of
which, taken together, shall be deemed to constitute one and the same agreement.




<PAGE>


If the foregoing correctly sets forth our mutual agreement, please so
acknowledge by signing and returning this Amendment to the undersigned.



                                       Very truly yours,

                                       FORTIS CAPITAL CORP., AS AGENT AND LENDER


                                       By:
                                          --------------------------------------
                                       Name: Darrell H. Holley
                                       Title: Managing Director

                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


                                       U. S. BANK NATIONAL ASSOCIATION, AS LC
                                       ISSUER AND A LENDER


                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------


         ACCEPTED as of the date
         Second written above.

         BORROWER:

         INLAND PRODUCTION COMPANY

         By:
            ----------------------------------------
         Name:  Bill I. Pennington
         Title: President




<PAGE>


                              CONSENT AND AGREEMENT

         Inland Resources Inc. hereby consents to the provisions of this Second
Amendment to Third Amended and Restated Credit Agreement and the transactions
contemplated herein, and hereby ratifies and confirms its Guaranty dated as of
November 30, 2001, as amended, supplemented, or restated to the date hereof,
made by it for the benefit of Agent and Lenders, and agrees that its obligations
and covenants thereunder are unimpaired hereby and shall remain in full force
and effect.


                                            INLAND RESOURCES INC.

                                            By:
                                               ---------------------------------
                                            Name: Bill I. Pennington
                                            Title: Chief Financial Officer
                                            Dated:
                                                  ------------------------------






<PAGE>


                             COMPLIANCE CERTIFICATE

                                __________, 2002

         Reference is made to (i) that certain Third Amended and Restated Credit
Agreement dated as of November 30, 2001 (as amended, supplemented, or restated
to the date hereof, the "Original Agreement"), between Inland Production
Company, a Texas corporation ("Borrower"), Inland Resources Inc., a Washington
corporation ("Parent"), and ING (U.S.) Capital LLC, as Agent, and certain other
financial institutions, as Lenders and (ii) that certain Second Amendment to
Third Amended and Restated Credit Agreement dated as of May 31, 2002 between
Borrower, Fortis Capital Corp. and Lenders (the "Amendment"; the Original
Agreement as amended by the Amendment is herein referred to as the "Credit
Agreement"). Terms which are defined in the Credit Agreement and which are used
but not defined herein shall have the meanings given them in the Credit
Agreement. The undersigned, Marc MacAluso and Bill Pennington, do hereby certify
in the name, and on behalf, of Borrower that Borrower has made a thorough
inquiry into all matters certified herein and based upon such inquiry,
experience, and the advice of counsel, do hereby further certify that:

         1. Marc MacAluso and Bill Pennington are the duly elected, qualified,
and acting Chief Executive Officer and Chief Financial Officer, respectively of
Borrower.

         2. All representations and warranties made by any Restricted Person in
any Loan document delivered on or before the date hereof (including, without
limitation, the representations and warranties contained in Section 4 of the
Amendment) are true in all material respects on and as of the date hereof
(except to the extent that the facts upon which such representations are based
have been changed by the transactions contemplated in the Credit Agreement) as
if such representations and warranties had been made as of the date hereof.

         3. No Default exists on the date hereof.

         4. Each Restricted Person has performed and complied with all
agreements and conditions required in the Loan Document to be performed or
complied with by it on or prior to the date hereof.

         IN WITNESS WHEREOF, this instrument is executed by the undersigned as
of the date Second above written.



                                    INLAND PRODUCTION COMPANY


                                    By:
                                       -----------------------------------------
                                       Marc MacAluso
                                       Chief Executive Officer


                                    By:
                                       -----------------------------------------
                                       Bill I. Pennington
                                       Chief Financial Officer





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