AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT

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                                                                    EXHIBIT 10.2


                                 AMENDMENT NO. 1
                                       TO
                              EMPLOYMENT AGREEMENT


     THIS AMENDMENT NO. 1 TO EMPLOYMENT AGREEMENT (this "Amendment") is made and
entered into as of July 14, 1997, by and between XXXXXX NATURAL GAS SERVICES,
INC., a Delaware corporation (the "Corporation"), and A. XXXXXXX XXXXXXX
("Officer").

                                    RECITALS:

     WHEREAS, the Corporation and Officer have previously entered into that
certain Employment Agreement, dated as of June 11, 1991 (as the same may be
amended or otherwise modified from time to time, the "Employment Agreement");
and

     WHEREAS, the Corporation and Officer now desire to amend the Employment
Agreement in order to extend the period of Officer's employment with the
Corporation;

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

     SECTION 1. AMENDMENT TO EMPLOYMENT AGREEMENT. Section 2.1 of the Employment
Agreement is hereby amended, effective as of the date hereof, to read in its
entirety as follows:

               "2.1 Basic Term. The term of Officer's employment under this
             Agreement shall continue for 18 months from July 14, 1997, unless
             otherwise terminated pursuant to this Section 2 (the "Employment
             Period"); provided, however, that unless either party gives 60 days
             written notice prior to the expiration of such 18-month term or any
             successive one-year term as provided hereafter, the Employment
             Period shall be automatically extended for one additional year, and
             thereafter for additional successive one-year periods, unless
             terminated earlier pursuant to this Section 2."

     SECTION 2. EFFECT OF AMENDMENT. From and after the date hereof, the term
"Employment Period" as used in the Employment Agreement shall be deemed to refer
to the Employment Period as such term is defined in this Amendment. Except as
and to the extent expressly modified by this Amendment, the Employment Agreement
shall remain in full force and effect in all respects in accordance with its
terms, and any reference to the Employment Agreement from and after the date
hereof shall be deemed to be a reference to the Employment Agreement as modified
by this Amendment.

     SECTION 3. GOVERNING LAW. This Amendment shall be governed by and construed
in accordance with the laws of the State of Colorado.



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     SECTION 4. COUNTERPARTS. This Amendment may be executed in one or more
counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same instrument.

     IN WITNESS WHEREOF, this Amendment No. 1 to Employment Agreement has been
duly executed and delivered by or on behalf of the undersigned as of the date
first written above.


                                       CORPORATION:

                                       XXXXXX NATURAL GAS SERVICES, INC.



                                       By:  /s/ W. Xxxxxxx Xxxxxx
                                          -----------------------------------
                                          W. Xxxxxxx Xxxxxx, President




                                       EMPLOYEE:



                                            /s/ A. Xxxxxxx Xxxxxxx
                                       --------------------------------------
                                       A. Xxxxxxx Xxxxxxx


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