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                                                                   EXHIBIT 10.60

                    SIXTH AMENDMENT TO FIRST RESTATED LOAN
                             AGREEMENT (REVOLVER)


     THIS SIXTH AMENDMENT TO FIRST RESTATED LOAN AGREEMENT (REVOLVER) (herein
called the "Amendment") made as of the 16th day of October, 1996, by and among
Western Gas Resources, Inc., a Delaware corporation ("Borrower"), NationsBank of
Texas, N.A., a national banking association, as Agent ("Agent"), and NationsBank
of Texas, N.A., Bank of Montreal, CIBC Inc., Societe Generale, Southwest Agency,
The First National Bank of Boston, Colorado National Bank, Bank of America
National Trust and Savings Association and Credit Lyonnais Cayman Island Branch,
(herein, collectively referred to as "Lenders").

                              W I T N E S S E T H:

     WHEREAS, Borrower, Agent and Lenders have entered into that certain First
Restated Loan Agreement (Revolver) dated as of September 2, 1994, as amended by
that certain First Amendment to First Restated Loan Agreement (Revolver) dated
as of December 2, 1994, that certain Second Amendment to First Restated Loan
Agreement (Revolver) dated as of February 23, 1995, that certain Third Amendment
to First Restated Loan Agreement (Revolver) dated as of July 19, 1995, that
certain Fourth Amendment to First Restated Loan Agreement (Revolver) dated as of
November 29, 1995, and that certain Fifth Amendment to First Restated Loan
Agreement (Revolver) dated as of March 22, 1996 (as amended to the date hereof,
the "Original Agreement") for the purpose and consideration therein expressed,
whereby Lenders became obligated to make and made loans to Borrower as therein
provided; and

     WHEREAS, Borrower, Agent and Lenders desire to amend the Original Agreement
as expressly set forth herein;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
and agreements contained herein and in the Original Agreement and in
consideration of the loans which may hereafter be made by Lenders to Borrower,
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.

                                       1
 
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               "Amendment" means this Sixth Amendment to First Restated Loan
                ---------                                                   
          Agreement (Revolver).

               "Loan Agreement" shall mean the Original Agreement as amended
                --------------
          hereby.



                           ARTICLE II. -- Amendments
                                          ----------

          Section 2.1.  Debt to Capitalization Ratio.  Section 6.2(m) of the
                        ----------------------------                        
Original Agreement is hereby amended in its entirety to read as follows:

                 "(m) Debt to Capitalization Ratio.  Borrower's Debt to 
                      ----------------------------
          Capitalization Ratio will never be greater than (i) 0.60 to 1.0 at any
          time until and including December 31, 1996 and (ii) 0.55 to 1.0 at any
          time thereafter."

                  ARTICLE III. -- Conditions of Effectiveness
                                  ---------------------------

          Section 3.1.  Effective Date.  This Amendment shall become effective
                        --------------                                        
as of the date first above written, except as otherwise provided herein, when,
and only when, Agent shall have received, at Agent's office, all of the
following:

                  (a)  Amendment.  A counterpart of this Amendment executed and
                       ---------                                               
          delivered by Borrower and all Lenders.

                  (b) Officer's Certificate.  A certificate of a duly 
                      ---------------------   
          authorized officer of Borrower, dated the date of receipt thereof by
          Agent, duly authorized, executed and delivered, and in form and
          substance satisfactory to Agent, to the effect that all of the
          representations and warranties set forth in Article IV hereof are true
          and correct at and as of the time of such effectiveness.

                 ARTICLE IV. -- Representations and Warranties
                                ------------------------------

          Section 4.1.  Representations and Warranties of Borrower.  In order to
                        ------------------------------------------              
induce each Lender to enter into this Amendment, Borrower represents and
warrants to each Lender that:

                  (a) The representations and warranties contained in each
          subsection of Section 5.1 of the Original Agreement are true and
          correct at and as of the time of the effectiveness hereof.

                  (b) Borrower is duly authorized to execute and deliver this
          Amendment and is and will continue to be duly authorized to borrow
          monies and to perform its obligations under the Loan Agreement.
          Borrower has duly taken all corporate action necessary to authorize
          the execution and delivery of this Amendment and to authorize the
          performance of the obligations of Borrower hereunder.

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                  (c) The execution and delivery by Borrower of this Amendment,
          the performance by Borrower of its obligations hereunder and the
          consummation of the transactions contemplated hereby do not and will
          not conflict with any provision of law, statute, rule or regulation or
          of the certificate of incorporation and bylaws of Borrower, or of any
          material agreement, judgment, license, order or permit applicable to
          or binding upon Borrower, or result in the creation of any lien,
          charge or encumbrance upon any assets or properties of Borrower.
          Except for those which have been 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
          Borrower of this Amendment or to consummate the transactions
          contemplated hereby.

                  (d) When duly executed and delivered, each of this Amendment
          and the Loan Agreement will be a legal and binding obligation of
          Borrower, enforceable in accordance with its terms, except as limited
          by bankruptcy, insolvency or similar laws of general application
          relating to the enforcement of creditors' rights and by equitable
          principles of general application.

                  (e) The unaudited quarterly Consolidated financial statements
          of Borrower dated as of June 30, 1996 fairly present Borrower's
          Consolidated financial position at such date and the Consolidated
          results of Borrower's operations and changes in Borrower's
          Consolidated cash flow for the period thereof. Copies of such
          financial statements have heretofore been delivered to each Lender.
          Since June 30, 1996, no material adverse change has occurred in the
          financial condition or businesses or in the Consolidated financial
          condition or businesses of Borrower.

                          ARTICLE V. -- Miscellaneous
                                        -------------

          Section 5.1.  Ratification of Agreements.  The Original Agreement as
                        --------------------------                            
hereby amended and each other Loan Document affected hereby are ratified and
confirmed in all respects.  Any reference to the Loan Agreement in any Loan
Document shall be deemed to be a reference to the Original Agreement as hereby
amended.  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 Lenders under the Loan Agreement, or any
other Loan Document nor constitute a waiver of any provision of the Loan
Agreement, or any other Loan Document.

          Section 5.2.  Survival of Agreements.  All representations,
                        ----------------------                       
warranties, covenants and agreements of Borrower herein shall survive the
execution and delivery of this Amendment and the performance hereof, including
without limitation the making or granting of the Loans, 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 Borrower or
any Related Person hereunder or under the Loan Agreement to any Lender shall be
deemed to constitute representations and warranties by, and/or agreements and
covenants of, Borrower under this Amendment and under the Loan Agreement.

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          Section 5.3.  Loan Documents.  This Amendment is a Loan Document, and
                        --------------                                         
all provisions in the Loan Agreement pertaining to Loan Documents apply hereto.

          Section 5.4.  Governing Law.  This Amendment shall be governed by and
                        -------------                                          
construed in accordance with the laws of the State of Texas and any applicable
laws of the United States of America in all respects, including construction,
validity and performance.

          Section 5.5.  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.

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


                                             WESTERN GAS RESOURCES, INC.



                                             By: /s/ John C. Walter
                                                -------------------------------
                                                John C. Walter
                                                Executive Vice President



                                             NATIONSBANK OF TEXAS, N.A.,
                                              as Agent, Issuing Bank and Lender



                                             By: /s/ Malcolm Turner
                                                --------------------------------
                                                Malcolm Turner
                                                Senior Vice President



                                             BANK OF AMERICA NATIONAL
                                             TRUST AND SAVINGS ASSOCIATION



                                             By: /s/ Gary M. Tsuyuki
                                                ------------------------------
                                                Gary M. Tsuyuki
                                                Vice President



                                             BANK OF MONTREAL



                                             By:   /s/ Don Skipper
                                                --------------------------------
                                                Don Skipper
                                                Director

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                                             THE FIRST NATIONAL BANK
                                              OF BOSTON



                                             By: /s/ Michael Kane
                                                --------------------------------
                                                Michael Kane
                                                Managing Director



                                             CREDIT LYONNAIS CAYMAN
                                             ISLAND BRANCH



                                             By: /s/ Pascal Poupelle
                                                --------------------------------
                                                Pascal Poupelle
                                                Senior Vice President


                                             CIBC INC.



                                             By: /s/ Gary C. Gaskill
                                                --------------------------------
                                                Gary C. Gaskill
                                                Vice President


                                             COLORADO NATIONAL BANK



                                             By: /s/ Kathryn S. Gaiter
                                                --------------------------------
                                                Kathryn S. Gaiter
                                                Vice President


                                             SOCIETE GENERALE, SOUTHWEST
                                              AGENCY


                                             By: /s/ Richard A. Erbert
                                                --------------------------------
                                                Richard A. Erbert
                                                Vice President

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            CONFIRMATION, ACKNOWLEDGEMENT AND CONSENT OF GUARANTORS


     Each of the undersigned (collectively "Guarantors") hereby (i) acknowledges
and consents to the foregoing Sixth Amendment to First Restated Loan Agreement
(Revolver) of even date herewith by and among Western Gas Resources, Inc.,
NationsBank of Texas, N.A., as Agent ("Agent"), Bank of Montreal, CIBC Inc.,
Societe Generale, Southwest Agency, The First National Bank of Boston, Colorado
National Bank, Bank of America National Trust and Savings Association and Credit
Lyonnais Cayman Island Branch; (ii) confirms the Restated Guaranty dated as of
September 2, 1994 executed by such Guarantor in favor of Agent and the Lenders
pursuant to the Original Agreement; and (iii) agrees that each of such
Guarantor's obligations and covenants with respect to such Restated Guaranty
shall remain in full force and effect after the execution of such Amendment.

     William J. Krysiak, Vice President-Finance of Western Gas Resources
Oklahoma, Inc., Western Gas Resources Texas, Inc., Western Gas Resources
Storage, Inc., Mountain Gas Resources, Inc., MGTC, Inc. and MIGC, Inc., is
executing this Confirmation, Acknowledgment and Consent of Guarantors in his
capacity of officer of each such corporation.

     Dated as of the 16th day of October, 1996.

                               WESTERN GAS RESOURCES OKLAHOMA, INC.
                               WESTERN GAS RESOURCES TEXAS, INC.
                               WESTERN GAS RESOURCES STORAGE, INC.
                               MOUNTAIN GAS RESOURCES, INC.
                               MGTC, INC.
                               MIGC, INC.



                               By: /s/ William J. Krysiak
                                   ----------------------------------------
                                   William J. Krysiak, Vice President-Finance

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