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            SIXTH AMENDMENT TO THIRD RESTATED LOAN AGREEMENT (TERM)

     THIS SIXTH AMENDMENT TO THIRD RESTATED LOAN AGREEMENT (TERM) (herein called
the "Amendment") made as of the 29th day of November 1995, 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., Bankers Trust Company, Bank of Montreal and CIBC Inc. (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 Third
Restated Loan Agreement (Term) dated as of August 31, 1993, as amended by that
certain First Amendment to Third Restated Loan Agreement (Term) dated as of
December 31, 1993, that certain Second Amendment to Third Restated Loan
Agreement (Term) dated as of September 2, 1994, that certain Third Amendment to
Third Restated Loan Agreement (Term) dated as of December 2, 1994, that certain
Fourth Amendment to Third Restated Loan Agreement (Term) dated as of February
23, 1995, and that certain Fifth Amendment to Third Restated Loan Agreement
(Term) dated as of July 19, 1995, among Borrower, Agent and Lenders (as amended
to the date hereof, the "Original Agreement") for the purpose and consideration
therein expressed, whereby Lenders 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.

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

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                                                                   Exhibit 10.50
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                                  ARTICLE II.

                                  Amendments
                                  ----------

     Section 2.1.  Definitions.  Section 1.1 of the Original Agreement is hereby
                   -----------                                                  
amended by adding a new definition of "1995 Note Purchasers Group" to read as
follows:

          "'1995 Note Purchasers Group' means, collectively, The Variable
           ----------------------------                                  
Annuity Life Insurance Company, American General Life Insurance Company, Gulf
Life Insurance Company, First Allmerica Financial Life Insurance Company,
Allmerica Financial Life Insurance and Annuity Company, and The Mutual Life
Insurance Company of New York."


     The definition of "Debt Securities" contained in Section 1.1 of the
Original Agreement is hereby amended in its entirety to read as follows:

     "'Debt Securities' means collectively, (i) those senior notes dated October
       ---------------                                                          
27, 1992, September 22, 1993, December 27, 1993 and October 27, 1994 issued by
Borrower pursuant to that certain Master Shelf Agreement dated as of December
19, 1991 between Borrower and The Prudential Insurance Company of America (as
amended and restated from time to time, the "Shelf Agreement") and any
additional notes issued pursuant to the Shelf Agreement (ii) the 7.65% senior
notes due April 30, 2003 in the aggregate principal amount of $50,000,000 issued
by Borrower pursuant to various note purchase agreements among Borrower, MIGC,
MGTC, WGRS, WGRT and each member of the CIGNA Group, as amended and restated
from time to time, (iii) the 8.02% senior notes due November 29, 2005 in the
aggregate principal amount of $42,000,000 issued by Borrower pursuant to a note
purchase agreement among Borrower and members of the 1995 Note Purchasers Group
(as amended and restated from time to time, the "1995 Note Purchase Agreement")
and (iv) all other notes issued pursuant to note purchase agreements among any
Related Person and any member of the CIGNA Group, the members of the 1995 Note
Purchasers Group, Prudential Insurance Company of America, or any other
institutional investor."
 
     Section 2.2.  Books, Financial Statements and Reports.  Section 5.1(b) of
                   ---------------------------------------                    
the Original Agreement is hereby amended by adding a new clause (vi), to read as
follows:

          "(vi)  as soon as delivered to such Persons, all other reports,
     statements and notices delivered to any holder of Debt Securities."


     Section 2.3  Insurance.  Section 5.1(h) of the Original agreement is hereby
                  ---------                                                     
amended by deleting the second sentence thereof.

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     Section 2.4.  Events of Default.  Section 7.1(l) of the Original Agreement
                   -----------------                                           
is hereby amended in its entirety to read as follows:

          "(l)  Without (i) the express prior written consent of all Lenders,
     Borrower amends or modifies the terms of any of the documents or
     instruments governing, or otherwise executed in connection with, any of the
     Debt Securities (a) shortening the maturity of such Debt Securities, (b)
     increasing the interest rate or fees payable under such Debt Securities or
     with respect to such Debt Securities, or (c) increasing the maximum
     principal amount of such Debt Securities, or (ii) the express prior written
     consent of Majority Lenders, Borrower amends or modifies any terms of any
     of the documents or instruments governing, or otherwise executed in
     connection with, any of the Debt Securities other than as set forth in the
     foregoing clause (i) of this subsection (l);  or"

 
                                 ARTICLE III.

                          Conditions of Effectiveness
                          ---------------------------

     Section 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, (i) a counterpart of this Amendment executed and delivered by
Borrower and all Lenders and (ii) each of the following, each document
(unless otherwise indicated) being dated the date of receipt thereof by Agent,
duly authorized, executed and delivered, and in form and substance satisfactory
to Agent:

          (a)  a certificate of the Secretary of Borrower dated the date of this
     Amendment certifying that: (A) the resolutions adopted by the Board of
     Directors of Borrower attached as Exhibit 1 to the Omnibus Certificate of
     Borrower dated September 2, 1994 (the "Original Certificate") have not been
     amended or revoked, and continue in full force and effect, (B) the
     incumbency and authorization of the officers of Borrower authorized to sign
     Loan Documents, with signature specimens of such officers, contained in the
     Original Certificate has not been amended and continues in full force and
     effect, (C) copies of the certified charter documents of Borrower
     (including by-laws), attached as Exhibits H and O to the Original
     Certificate have not been amended or revoked since the date of the Original
     Certificate, and continue in full force and effect, (D) no Default that has
     not been expressly waived by Lenders exists on and as of the date hereof
     and (E) all of the representations and warranties set forth in Article IV
     hereof and Article IV of the Original Agreement are true and correct at and
     as of their respective times of effectiveness;

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          (b)  a favorable opinion from Messr. John Walter, Esq., counsel for
     Borrower in a form acceptable to Lender; and

          (c)  such supporting documents as Agent may reasonably request.

                                  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 4.1 of the Original Agreement are true and correct at and as of
     the time of the effectiveness hereof, except for representations and
     warranties relating to rights of way and easements for the Katy Gas Storage
     Facility modified as set forth in Schedule 1 hereto.

          (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 and thereunder.

          (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 articles 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, 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 audited annual Consolidated financial statements of Borrower
     dated as of December 31, 1994 and the

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     unaudited quarterly Consolidated financial statements of Borrower dated as
     of September 30, 1995 fairly present Borrower's Consolidated financial
     position at such dates and the Consolidated results of Borrower's
     operations and changes in Borrower's Consolidated cash flow for the
     respective periods thereof.  Copies of such financial statements have
     heretofore been delivered to each Lender.  Since September 30, 1995, 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.  Consent to 1995 Note Purchase Agreement.  Each Lender
                   ---------------------------------------              
consents and agrees that the 8.02% senior notes issued by Borrower pursuant to
the 1995 Note Purchase Agreement comply with the provision of Section
5.2(b)(viii) of the Loan Agreement.

     Section 5.2.  Consent to Amendment to Shelf Agreement.  Each Lender
                   ---------------------------------------              
consents and agrees that the Shelf Agreement as modified by the amendment dated
November 29, 1995 complies with the provisions of Section 5.2(b)(viii) of the
Loan Agreement and each Lender further consents to such modifications for
purposes of Section 7.1(i) of the Loan Agreement.

     Section 5.3.  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, 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 5.4.  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.

     Section 5.5.  Loan Documents.  This Amendment is a Loan Document, and all
                   --------------                                             
provisions in the Loan Agreement pertaining to Loan Documents apply hereto.

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     Section 5.6.  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 5.7.  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, 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
                                          ------------------
                                       Name:  John C. Walter
                                       Title: Executive Vice President
                                     
                                     
                                       NATIONSBANK OF TEXAS, N.A.
                                     
                                     
                                       By:/s/  Michele L. Jones
                                          ---------------------
                                          Name: Michele L. Jones
                                          Title: Vice President
                                     
                                     
                                       BANKERS TRUST COMPANY
                                       
                                     
                                       By:/s/  Mary Jo Jolly
                                          ---------------------
                                          Name: Mary Jo Jolly
                                          Title:  Assistant Vice     
                                          President
                                     
                                     
                                       BANK OF MONTREAL
                                       
                                     
                                       By:/s/ Michael P. Stuckey
                                          -------------------------
                                          Name: Michael P. Stuckey
                                          Title: Director, U.S.     
                                          Corporate Banking

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                                  CIBC INC.


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

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                                  SCHEDULE 1

Borrower hereby represents and warrants that, with respect to Western Gas
Resources Storage, Inc.'s Katy Hub and Gas Storage Facility: (a)  the
condemnation process relating to certain storage rights, rights-of-way and well
easements has not been completed and therefore, as of the date hereof, Western
Gas Resources Storage, Inc. has, with respect to such storage rights, rights-of-
way and well easements, only the right to the possession thereof (such right to
possession being sufficient to enable Western Gas Resources Storage, Inc. to
conduct its business and operations at the Katy Hub and Gas Storage Facility as
is currently conducted and as proposed to be conducted) and (b) when such
condemnation process is completed and Western Gas Resources Storage, Inc. has
paid all amounts determined to be due to the condemnee with respect thereto,
Western Gas Resources Storage, Inc. will obtain good and defensible title to
said storage rights, rights-of-way and well easements.

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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 Third Restated Loan Agreement
(Term); (ii) confirms the Restated Guaranty dated as of August 31, 1993 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 29th day of November, 1995.

                                  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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