Amendment Four to Credit Agreement

This Amendment Four to Credit Agreement (“Amendment”) is dated as of , 2004, among MATRIX SERVICE COMPANY, as Borrower, the Lenders and BANK ONE, NA (as successor by merger to Bank One, Oklahoma, NA), with its main office in Chicago, Illinois, as a Lender and as Agent for the Lenders.

J. Reference is made to the Credit Agreement dated as of March 7, 2003, among Borrower, Lenders and Agent, as amended by Amendment One to Credit Agreement dated as of May 22, 2003, Amendment Two to Credit Agreement dated as of August 27, 2003, and Amendment Three to Credit Agreement dated as of December 19, 2003 (as amended, the “Credit Agreement”) pursuant to which each of the Lenders established their respective Commitments in favor of the Borrower.

K. Borrower has requested the Lenders to amend the pricing as to the Temporary Over-Advance; and the Lenders and Agent have agreed thereto, subject to the terms and conditions set forth below.

L. Terms used herein shall have the meanings ascribed to them in the Credit Agreement, unless otherwise defined herein.

1.10 Temporary Over-Advance-Increase. Lenders and Agent agree that the term “Borrowing Base” as used in Sections 2.1.1 and 2.7.2(iv) shall read “Borrowing Base plus $15,000,000” until the earliest of: (a) December 31, 2004; (b) the occurrence of Default; or (c) upon the failure of Borrower to maintain outstanding Revolving Loans and LC Obligations equal to or below the Borrowing Base for at least five (5) consecutive Business Days during each month through December 31, 2004; whereupon, the words “plus $15,000,000” shall be automatically deleted without any action by the Agent. With respect to any amounts outstanding in excess of the Borrowing Base, the Applicable Margin for Eurodollar Loans and ABR Loans shall be increased by 25 basis points.

21. Representations. Borrower represents to Agent and Lenders that: (i) their exists no Default or Unmatured Default; (ii) the representations and warranties contained in Article V of the Loan Agreement are true and correct as of the date hereof, except to the extent such representation or warranty is stated to relate solely to an earlier date, in which case such

representation or warranty shall have been true and correct on and as of such earlier date; and (iii) it is in compliance with the financial covenants as set forth in Section 6.27.

22. Ratifications. Borrower shall deliver to Agent fully executed originals of the Ratification of Security Agreements and Ratification of Guaranty Agreement, in the forms set forth on Schedules “3-A” and “3-B”, respectively, attached hereto.

23. Governing Law. This Amendment shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of Oklahoma.

24. Reimbursement. Borrower agrees to reimburse Agent for any costs, expenses, and fees (including reasonable attorney fees) incurred in connection with the preparation of this Amendment.

25. Counterparts. This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one agreement, and any of the parties hereto may execute this Agreement by signing any such counterpart. This Agreement shall be effective when it has been executed by the Borrower, the Agent, the LC Issuer and the Lenders and each party has notified the Agent by facsimile transmission or telephone that it has taken such action.

IN WITNESS WHEREOF, the Borrower, the Lenders, the LC Issuer and the Agent have executed this Amendment as of the date first above written.


MATRIX SERVICE COMPANY

By:
		Michael J. Hall, Vice President



Notice Address:		10701 East Ute Street Tulsa, OK 74116
Attention:		Michael J. Hall, Vice President
Telephone:		(918) 838-8822
FAX:		(918) 838-8810


BANK ONE, NA (as successor by merger to Bank One, Oklahoma, NA)
Individually and as Agent and LC Issuer

By:
		David G. Page, First Vice President



Notice Address:		4^th Floor OK2-6110 15 East Fifth Street Tulsa, OK 74103
Attention:		David G. Page, First Vice President
Telephone:		(918) 586-5430
FAX:		(918) 586-5474