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                   FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER

    This FIRST AMENDMENT TO AGREEMENT AND PLAN OF MERGER (this "Amendment"), 
dated as of this 30th day of July, 1997, is by and among  EQUITY COMPRESSION 
SERVICES CORPORATION, an Oklahoma corporation (the "Parent"), OEC ACQUISITION 
CORPORATION, a Delaware corporation and a wholly owned subsidiary of Parent 
(the "Merger Sub"), OUACHITA ENERGY CORPORATION, a Louisiana corporation (the 
"Company") and DENNIS W. ESTIS (the "Shareholder").  The Parent, the Merger 
Sub, the Company and the Shareholder are sometimes collectively referred to 
herein as the "Parties" and individually as a "Party".

                                 W I T N E S S E T H

    WHEREAS, the Parties are parties to that certain Agreement and Plan of 
Merger dated as of May 15, 1997 (the "Merger Agreement"); and

    WHEREAS, the Parties now desire to amend the Merger Agreement as set 
forth herein;

    NOW, THEREFORE, in consideration of the premises and of the respective 
representations, warranties, covenants, agreements and conditions contained 
herein, the Parties, intending to be legally bound, hereto agree as follows:

1.  DEFINED TERMS; CONTROLLING AGREEMENT.  

    1.01 DEFINED TERMS.  Unless defined herein or unless the context clearly 
indicates to the contrary, all defined or capitalized terms contained in the 
Merger Agreement shall have the same meaning in this Amendment as in the 
Merger Agreement.

    1.02 CONTROLLING AGREEMENT.  Unless specifically modified or amended 
herein, the Merger Agreement shall remain in full force and effect.  In the 
event of any inconsistency between this Amendment and the Merger Agreement, 
the terms of this Amendment shall control.

2.  MODIFICATIONS TO THE MERGER AGREEMENT.   The Parties agree that the 
Closing Date shall be August 1, 1997 of such other date as the Parties shall 
agree, and the outside date for the Closing set forth in Section 9.1(B) shall 
be August 15, 1997.
  
3.  MISCELLANEOUS.

    3.01 EXCLUSIVE AGREEMENT.  The Merger Agreement, as amended by this 
Amendment, together with the Asset Purchase Agreement, the Exhibits, the 
Confidentiality Agreement, the Indemnification Agreement and any schedules or 
agreements delivered in connection with the Merger Agreement or the 
consummation of the Merger supersedes all prior agreements among the Parties 
(written or oral) 

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and is intended as a complete and exclusive statement of the terms of the 
agreements among the Parties.

    3.02 CHOICE OF LAW; HEADING.  This Amendment shall be governed by the 
internal laws of the State of Texas.  The captions or headings contained in 
this Amendment are for reference purposes only and shall not affect in any 
way the meaning and interpretation of this Amendment.

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

    IN WITNESS WHEREOF, the undersigned have executed this Amendment as of 
the date first written above.

                                  EQUITY COMPRESSION SERVICES CORPORATION

                                  By:  _____________________
                                  Name:  ___________________
                                  Title:  __________________


                                  OEC ACQUISITION CORPORATION

                                  By:  _____________________
                                  Name:  ___________________
                                  Title:  __________________

                                  OUACHITA ENERGY CORPORATION

                                  By:  _____________________
                                  Name:  ___________________
                                  Title:  __________________

                                  __________________________
                                  DENNIS W. ESTIS

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