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     WAIVER, dated as of September 7, 1999 (this "Waiver"), to the CREDIT
AGREEMENT, dated as of March 31, 1997, (the "Credit Agreement") among IRI
INTERNATIONAL CORPORATION, a Delaware corporation (the "Borrower") as successor
to the merger of ENERGY SERVICES INTERNATIONAL LTD.,  a Delaware corporation and
former IRI INTERNATIONAL CORPORATION, a Delaware corporation, the several banks
and other financial institutions or entities from time to time parties thereto
(the "Lenders"), and CREDIT LYONNAIS NEW YORK BRANCH, as Administrative Agent
for the Lenders (in such capacity, the "Administrative Agent").


                             W I T N E S S E T H :

          WHEREAS, pursuant to the Credit Agreement the Borrower agreed to
comply with certain covenants contained in section 7.1. therein;

          WHEREAS, the Borrower have requested the Administrative Agent to waive
the compliance with certain of such covenants;

          WHEREAS, the parties hereto have determined that it is in the best
interest of the parties to agree and consent on the waiver for the periods
established herein;

          NOW, THEREFORE, in consideration of the premises and of the mutual
agreements herein contained, the parties hereto agree as follows:

          1.   Definitions. Unless otherwise defined herein, terms defined in
the Credit Agreement shall be used as so defined.

          2.   Waiver. The Administrative Agent and the Lenders hereby waive the
compliance by the Borrower with the following:

     (a)  Section 7.1(b) of the Credit Agreement for the fiscal quarters ending
          December 31, 1998 and March 31, 1999; and

     (b)  Sections 7.1(b), 7.1(c) and 7.1(d) of the Credit Agreement for the
          fiscal quarters ending June 30, 1999 and September 30, 1999.

          3.   No Revolving Credit Loans. From and after the date hereof, the
Revolving Credit Commitments shall be available for the issuance of Letters of
Credit only, and no Loans may be made or be outstanding.

          4.   Security Interest; Cash Collateral; Guarantee Letter of Credit.
If on the Revolving Credit Termination Date any Letters of Credit are
outstanding, or any amount remains unpaid in respect of any drawings under
Letters of Credit, then at the option of the Borrower:

     (i)  the security interest of the Administrative Agent on the Collateral
          will not be released and the Borrower shall not permit any Lien to be
          incurred on any asset

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          of the Borrower or any Subsidiary, until all amounts owing in respect
          of Letters of Credit are paid in full and no Letters of Credit are
          outstanding; or

     (ii) the Borrower will deposit with the Administrative Agent on the
          Revolving Credit Termination Date cash collateral in the amount
          equivalent to the undrawn amount of all such outstanding Letters of
          Credit, plus the amount of any unreimbursed drawings under such
          Letters of Credit, pursuant to a cash collateral agreement
          satisfactory to the Administrative Agent and until all amounts
          owing in respect of Letters of Credit are paid in full and no Letters
          of Credit are outstanding; or

    (iii) the Borrower will provide a letter of credit, satisfactory to the
          Administrative Agent, on the Revolving Credit Termination Date in the
          amount equivalent to the undrawn amount of all such outstanding
          Letters of Credit, plus the amount of any unreimbursed drawings under
          such Letters of Credit.

          5.   Effective Date. This Waiver will become effective as of the date
hereof upon its execution by the Borrower, the Lenders and the Administrative
Agent in accordance with the terms of the Credit Agreement.

          6.   Representative and Warranties. The Borrower represents and
warrants to each Lender that on the date hereof and on the effective date
hereof, prior to and after giving effect to the effectiveness of this Waiver (a)
the representations and warranties made by the Loan Parties in the Loan
Documents are true and correct in all material respects (except to the extent
that such representations and warranties are expressly stated to relate to an
earlier date, in which case such representations and warranties shall have been
true and correct in all material respects on and as of such earlier date) and
(b) no Default or Event of Default has occurred and is continuing.

          7.   Continuing Effect. Except as expressly waived hereby, the Credit
Agreement shall continue to be and shall remain in full force and effect in
accordance with its terms.

          8.   GOVERNING LAW. THIS WAIVER SHALL BE GOVERNED BY, AND CONSTRUED
AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

          9.   Counterparts. This Waiver may be executed by the parties hereto
in any number of separate counterparts, and all of said counterparts taken
together shall be deemed to constitute one and the same instrument.

          10.  Payment of Expenses. The Loan Parties agree to pay and reimburse
the Administrative Agent for all of its out-of-pocket costs and reasonable
expenses incurred in connection with this Waiver, including, without
limitation, the reasonable fees and disbursements of counsel to the
Administrative Agent.
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          IN WITNESS WHEREOF, the parties hereto have caused this Waiver to be
duly executed and delivered by their proper and duly authorized officers as of
the day and year first above written.





                                        IRI INTERNATIONAL CORPORATION




                                        By:__________________________
                                           Title:



                                        CREDIT LYONNAIS NEW YORK BRANCH, as
                                        Administrative Agent, Issuing Lender
                                        and as the sole Lender



                                        By:____________________________
                                           Title: