FIRST AMENDMENT TO CREDIT AGREEMENT

THIS FIRST AMENDMENT TO CREDIT AGREEMENT ("Amendment") is made and  entered
into this 19th day of June, 1997, by and among MATRIX SERVICE  COMPANY, a
Delaware corporation (hereinafter referred to as "Matrix"),  MATRIX
SERVICE, INC., an Oklahoma corporation (hereinafter to as "MSI"),  MIDWEST
INDUSTRIAL CONTRACTORS, INC., a Delaware corporation (hereinafter  referred
to as "MIC"), MATRIX SERVICE MID-CONTINENT, INC., an Oklahoma  corporation
(hereinafter referred to as "MSM"), PETROTANK EQUIPMENT, INC.,  an Oklahoma
corporation (hereinafter referred to as "PEI"), TANK SUPPLY  INC., an
Oklahoma corporation (hereinafter referred to as "TSI"), SAN LUIS  TANK
PIPING CONSTRUCTION CO., INC., a Delaware corporation (hereinafter 
referred to as "SLT"), COLT CONSTRUCTION CO., INC., a Delaware corporation 
(hereinafter referred to as "CCC"), MIDWEST INTERNATIONAL, INC., a Delaware 
corporation (hereinafter referred to as "MII"),  GEORGIA STEEL ACQUISITION 
CORPORATION, an Oklahoma corporation (hereinafter referred to as "GSAC"), 
GEORGIA STEEL FABRICATORS, INC., a Georgia corporation (hereinafter 
referred to as "GSF"), BROWN STEEL CONTRACTORS, INC., a Georgia corporation 
(hereinafter referred to as "BSC"), WEST COAST INDUSTRIAL COATINGS, INC., a 
California corporation (hereinafter referred to as "WCI"), MIDWEST SERVICE 
COMPANY, a Delaware corporation (hereinafter referred to as "MSC"), HEATH 
ENGINEERING, LTD., an Ontario corporation (hereinafter referred to as 
"HEL"), HEATH (TANK MAINTENANCE) ENGINEERING, LTD., a United Kingdom 
corporation (hereinafter referred to as "HTM"), MAYFLOWER VAPOR SEAL 
CORPORATION, an Oklahoma corporation (hereinafter referred to as ("MVS"), 
GENERAL SERVICE CORPORATION, a Delaware corporation (hereinafter referred 
to as "GSC"), MAINSERVE-ALLENTECH, INC., a Delaware corporation 
(hereinafter referred to as "MA"), MAINTENANCE SERVICES, INC., a Delaware 
corporation (hereinafter referred to as "MSERV"), and LIBERTY BANK AND 
TRUST COMPANY OF TULSA, NATIONAL ASSOCIATION (hereinafter referred to as 
the "Bank").  Matrix, MSI, MIC, MSM, PEI, TSI, SLT, CCC, MII, GSAC, GSF, 
BSC, WCI, MSC, HEL, HTM, MVS, GSC, MA and MSERV are hereinafter 
collectively referred to as the "Borrowers" and individually as a 
"Borrower."

      RECITALS

A.    The Borrowers (except for GSC, MA and MSERV) are parties to that 
certain Credit Agreement dated August 30, 1994 (the same as amended, 
supplemented or otherwise modified from time to time, being hereinafter 
referred to as the "Credit Agreement"), pursuant to which the Bank has 
established in favor of the Borrowers, on the terms and conditions set 
forth therein, (i) a revolving credit facility in the principal amount not 
to exceed $15,000,000.00, and (ii) a term loan facility in the original 
principal amount not to exceed $5,000,000.00.

B.    The Borrowers have requested that the Bank (i) extend the  maturity
of the Revolving Credit Facility from October 31, 1998 to October  31,
1999, (ii) establish a new $5,000,000 term acquisition facility, (iii)  add
GSC, MA and MSERV as Borrowers under the Credit Agreement and as a co-maker
on the Notes, and (iv) modify certain financial covenants and other 
provisions in the Credit Agreement, all as hereinafter set forth.


C.    The Bank has agreed to the foregoing, subject to the terms and 
conditions hereinafter set forth.

NOW THEREFORE, in consideration of the foregoing, and for other good and
valuable consideration, the receipt and adequacy of which are hereby 
acknowledged, and subject to the terms and conditions set forth herein, the
parties agree to amend the Credit Agreement, effective as of the date 
hereof, as follows:

1.    TERMS DEFINED IN THE CREDIT AGREEMENT.  

1.1   Definitions Incorporated by Reference.  Capitalized terms used 
herein and not otherwise defined have the respective meanings assigned to 
them in the Credit Agreement.

1.2   Definitions Used Only in This Amendment.  For purposes of this 
Amendment only, the following terms have the meanings indicated below:

Replacement Revolving Note.  "Replacement Revolving Note" shall mean  the
promissory note to be executed and delivered by the Borrowers, in 
substantially the form attached hereto as Exhibit "A-1."

Replacement Term Note.  "Replacement Term Note" shall mean the  promissory
note to be executed and delivered by the Borrowers, in  substantially the
form attached hereto as Exhibit "B-1."

The parties agree that, from and after the date of this Amendment,  unless
the context otherwise requires: (i) all references to the "Revolving  Note"
and the "Term Note" appearing in the Credit Agreement or any other  Loan
Documents shall mean and refer to the Replacement Revolving Note and  the
Replacement Term Note, respectively, together with any and all  renewals,
extensions or replacements thereof, amendments or modifications  thereto or
substitutions therefore, and (ii) the term "Loan Documents"  shall include
the Replacement Revolving Note and the Replacement Term Note.

2.    ADDITION OF GSC AND SUBSIDIARIES AS BORROWERS.   Pursuant to this 
Amendment, GSC, MA and MSERV agree to execute this Amendment, the 
Replacement Revolving Note, the Replacement Term Note, the Acquisition Note
and a Security Agreement, and hereafter all references in the Credit 
Agreement to the term "Borrowers" shall be deemed to include GSC, MA and 
MSERV.

3.    ESTABLISHMENT OF ACQUISITION LOAN FACILITY.  The Bank hereby agrees
to establish a new term loan in favor of the Borrowers in the principal
amount of $5,000,000.00.  In order to effectuate the foregoing, the Credit
Agreement is amended as of the date hereof in the following respects:

3.1   Amended Definitions.  The definitions of the following terms
appearing in Subsection 1.2 of the Credit Agreement are hereby amended to
read as follows:

Credit Facilities.  "Credit Facilities" shall mean, 
collectively, the Revolving Credit Facility, the Term Loan 
Facility and the Acquisition Loan Facility, and "Credit Facility"  shall
mean either one of the Credit Facilities.

Notes.  "Notes" shall mean collectively, the Revolving Note,  the Term Note
and the Acquisition Note, and "Note" shall mean any  one of the Notes.

3.2   New Definitions.  The following definitions of "Acquisition Loan
Facility," "Acquisition Note" and "GSC Purchase Agreement" are hereby added
to paragraph 1.2 of the Credit Agreement (to be inserted in alphabetical
order):

Acquisition Loan Facility.  "Acquisition Loan Facility" 
shall mean the term loan facility to be established by the Bank  in favor
of the Borrowers pursuant to Subsection 2.1.3 hereof.

Acquisition Note.  "Acquisition Note" shall mean the promissory note to
be executed by the Borrowers in order to  evidence all Advances made
under the Acquisition Loan Facility  pursuant to Subsection 2.6.4 hereof,
substantially in the form of  Exhibit "J" attached hereto, as the same
may be amended, modified, supplemented, renewed or extended from time to time.
GSC Purchase Agreement.  "GSC Purchase Agreement" shall mean  that certain
Purchase Agreement dated June 17, 1997 between Matrix  and the shareholders of
GSC for the purchase of 100% of the  outstanding issued shares of stock in
GSC.

3.3   Modified Subsections Required for Acquisition Loan Facility.  In 
order to effectuate the terms and conditions of the Acquisition Loan 
Facility the Credit Agreement shall be modified in accordance with the 
following:

A.    Modifications to Subsection 2.1.  Subsection 2.1 of the Credit 
Agreement is hereby modified and shall hereafter be deemed to include the 
following Subsection 2.1.3:

2.1.3 Acquisition Loan Facility.  The Bank agrees, upon satisfaction of
the Conditions set forth in Subsection 6 of the  Amendment, to establish
a term loan facility, to be designated as  the "Acquisition Loan Facility,"
in an aggregate principal amount  not to exceed Five Million and No/100
Dollars ($5,000,000.00).

B.    Modification to Subsection 2.2.  Subsection 2.2 of the Credit
Agreement is hereby modified and shall hereafter be deemed to
include the  following Subsection 2.2.3:

2.2.3 Acquisition Loan Facility.  Proceeds of the Acquisition Loan 
Facility shall be used by Borrowers solely for the purpose of paying down 
Advances under the Revolving Credit Facility which were incurred in the 
Borrowers' acquisition of the ownership of GSC (and its subsidiaries) and 
the refinancing of equipment owned by GSC.

C.    Modifications to Subsection 2.6.  Subsection 2.6 of the Credit
Agreement is  hereby modified and shall hereafter be deemed to include the
following Subsection  2.6.4:

2.3.4 Acquisition Note.  The balance outstanding under the Acquisition
Loan Facility shall be evidenced by the Acquisition Note, which shall be
made, executed and delivered by the Borrowers as a condition of this
Amendment.

D.    Modifications to Subsection 2.7.3(c) and (g).  Subsections 2.7.3(c)
and (g)  of the Credit Agreement shall hereafter be modified to read in
their entirety as  follows:

(c)   no Interest Period shall extend beyond October 31, 1999 (in  the case
of outstanding Advances under the Revolving Note), August 31,  1999 (in the
case of outstanding Advances under the Term Note), and June 19, 2002 (in
the case of the outstanding principal balance under  the Acquisition Note);


(g)   notwithstanding any provisions herein to the contrary, the  Borrowers
may select an Interest Period of less than 30 days for Advances included
within the Prime Tranche if such shorter period ends  on October 31, 1999
(in the case of outstanding Advances under the  Revolving Note), and August
31, 1999 (in the case of outstanding  Advances under the Term Note), and
the Borrowers may select an  Interest Period of less than 30 days when
continuing or converting any  portion of the outstanding balance under the
Acquisition Loan Facility  included within the Prime Tranche if such
shorter period ends on June 19, 2002.

D.    Modification to Subsection 2.7.  Subsection 2.7 of the Credit 
Agreement is hereby modified and shall hereafter be deemed to include the 
following Subsection 2.7.6:

2.7.6 Acquisition Note.

(a)   Interest Rate Election.  Prior to the effectiveness of this 
Amendment, the Borrowers shall irrevocably elect in writing either a fixed 
rate of interest (in accordance with the provisions of Subsection 2.7.6 (b) 
hereof) or a variable rate of interest (in accordance with the provisions 
of Subsection 2.7.6(c) hereof) to apply to the amounts outstanding under 
the Acquisition Note.

(b)   Fixed Rate Option.  If the Borrowers elect a fixed rate pursuant  to
Subsection 2.7.6(a) hereof, the unpaid amounts outstanding under the 
Acquisition Note shall bear interest at a fixed rate per annum equal to the
sum of the Two-Year Treasury Rate plus two percent (2%). In the event of
any Event of Default and until cured to the satisfaction of the Bank, the
unpaid principal amount and all accrued and unpaid interest outstanding
under the Acquisition Note shall bear interest at a fixed rate per annum
equal to the sum of the Two-Year Treasury Rate plus four percent (4%).

(c)   Variable Rate Option.  If the Borrowers elect a variable rate 
pursuant to Subsection 2.7.6(a) hereof, the unpaid principal amounts 
outstanding under the Acquisition Note shall bear interest at a variable 
rate per annum determined by reference to the Prime Rate or the LIBOR Rate, 
as selected by the Borrowers pursuant to a Rate Election made in accordance 
with the provisions of Subsection 2.7.3 hereof, as follows:

(i)   Amounts outstanding under the Acquisition Note included within the
Prime Tranche shall bear interest at a fluctuating rate per annum equal to
the Prime Rate, adjusted as of the date of each change therein.

(ii)  Amounts outstanding under the Acquisition Note included within the
LIBOR Tranche shall bear interest at a rate per annum equal to the sum of
the LIBOR Rate applicable to such LIBOR Tranche plus two percent (2%).

(iii) In the event of any Event of Default and until cured to the
satisfaction of the Bank, the unpaid principal amount outstanding under
the Acquisition Term Note shall bear interest at a fluctuating rate per
annum equal to the Prime Rate plus two percent (2%), adjusted as of the
date of each change therein.

E.    Modifications to Subsection 2.8.  Subsection 2.8 of the Credit
Agreement is  hereby modified and shall hereafter be deemed to include the
following Subsection  2.8.4:

2.8.4 Acquisition Loan Facility Fee.  As a condition of this  Amendment,
the Borrowers shall pay to the Bank a nonrefundable "Acquisition  Loan
Facility Fee" in the amount of $12,500.00.

F.    Modifications to Subsection 2.9.  Subsection 2.9 of the Credit
Agreement is  hereby modified and shall hereafter be deemed to include the
following Subsection  2.9.3:

2.9.3 Acquisition Note.  The outstanding balance under the Acquisition
Note shall be due and payable in six (6) monthly installments of interest
only, and thereafter in fifty-four (54) monthly installments of principal
and interest, calculated on the basis of a sixty (60) month amortization,
which installments shall be made on the first Business Day of each calendar
month beginning on the first Business Day of the first calendar month
following the date hereof.  The final maturity of the Acquisition Note
shall be June 19, 2002, and on that date the outstanding principal balance
and all accrued and unpaid interest under the Acquisition Note shall be due
and payable.

4. EXECUTION OF REPLACEMENT REVOLVING NOTE AND EXTENSION OF REVOLVING
   CREDIT FACILITY MATURITY DATE.

4.1   Execution of Replacement Revolving Note.  The Revolving Note, as in
effect on the date hereof, has a maturity date of October 31, 1999, and
the Borrowers hereby  agree to execute the Replacement Revolving Note to
add GSC, MA and MSERV as co-makers  on the Revolving Note, which shall
retain a maturity date of October 31, 1999.

4.2   Extension of Revolving Credit Facility Maturity Date.  Approval from
a  Participating Lender is required in order to effectuate an extension of
the termination date of the Revolving Credit Facility in accordance with
Subsection 2.13  of the Credit Agreement.  Upon obtaining requisite
approvals from any participating  lenders, the Borrowers agree to execute
and deliver a replacement to the Replacement  Revolving Note, which note
shall have a maturity date of October 31, 1999, and upon  delivery of such
note to the Bank, all references in the Credit Agreement to the termination
date or maturity date of the Revolving Note shall thereafter be deemed to
refer to October 31, 1999.

5.    MODIFICATIONS TO FINANCIAL COVENANTS.

5.1   Tangible Net Worth.  Subsection 7.11.1 of the Credit Agreement is
hereby  modified and amended and shall hereafter be deemed to include the
additional  requirement that after May 31, 1997, the Borrowers will not
permit their consolidated  tangible net worth (determined in accordance
with GAAP) to be less than  $45,000,000.00.

5.2   Working Capital.  Subsection 7.11.2 of the Credit Agreement is hereby
modified  and amended to delete the dollar amount stated as "$12,500,000.00"
and  replace that dollar amount with the dollar amount stated as
"$18,000,000.00."

5.3   Cash Flow Coverage Ratio.  From and after the date hereof, the Bank
agrees  to waive the Borrowers' compliance with the Cash Flow Coverage
Ratio contained in  Subsection 7.11.4 of the Credit Agreement until
February 28, 1998, and the Borrowers  agree that from and after February
28, 1998 the Borrowers shall be subject to and in  compliance with
Subsection 7.11.4 of the Credit Agreement.

6.    CONDITIONS.  The amendments to the Credit Agreement set forth in this
Amendment  shall be effective from and after the date hereof, but subject
to the Borrowers'  satisfaction of each of the following conditions precedent:

6.1   GSC Purchase Agreement.  The Bank shall have received a final copy of
the  GSC Purchase Agreement (the terms of which must be satisfactory to the
Bank), and the  closing of the transactions contemplated by the GSC Purchase
Agreement (including the  equipment refinancing) shall have occurred.

6.2   Loan Amendment Documents.  The Borrowers shall have duly and validly 
authorized, executed and delivered to the Bank, the following documents,
all in form  and substance satisfactory to the Bank:

(a)   This Amendment;

(b)   The Acquisition Note;

(c)   The Replacement Revolving Note;

(d)   The Replacement Term Note;

(e)   Security Agreements, executed by GSC, MA and MSERV, respectively, in 
      favor of the Bank; and

(f)   Appropriate UCC-1 financing statements, executed by GSC, MA and
      MSERV.

6.3   Corporate Documents.  With respect to GSC, MA and MSERV, the Bank
shall  have received: (i) a true and correct copy of their Articles or
Certificate of  Incorporation, as amended; (ii) a true and correct copy of
their Bylaws, as amended;  and (iii) a good standing certificate issued by
the Secretary of State or equivalent  public official of the state or
jurisdiction of their incorporation, as to their due  incorporation and
good standing under the laws of such state or jurisdiction.

6.4   Resolutions.  With respect to each of  the Borrowers, the Bank shall
have  received a true and correct copy of the resolutions adopted by its
Board of Directors  duly authorizing the borrowings contemplated hereunder
and the execution, delivery  and performance of the Loan Documents to which
it is a party.

6.5   Incumbency Certificates.  With respect to each of the Borrowers, the
Bank  shall have received a certificate executed by its duly elected and
acting corporate  secretary stating the names and titles and containing
specimen signatures of the  officers authorized to execute and deliver the
Loan Documents to which it is a party.

6.6   Payoff Letter.  The Bank shall have received a satisfactory payoff
letter  from the holder of the existing equipment financing facility with
GSC, (i) stating  the amount necessary to pay off the principal balance of
and accrued interest on such  equipment financing facility, (ii) setting
froth payment instruction for remitting  the payoff amount, (iii) stating
that, immediately upon receipt of the payoff amount,  said holder will
release any Liens which it may have in or to the Collateral (or any 
portion thereof) and will deliver or cause to be filed UCC termination
statements  with respect to all currently effective financing statement of
file in any UCC office  naming GSC, MA or MSERV as debtor and covering the
Collateral (or any portion  thereof), and (iv) acknowledging that, upon
such holder's receipt of the payoff  amount, it will no longer have and
Lien on the Collateral (or any portion thereof) to  secure any Debt now or
hereafter owing to it by GSC, MA or MSERV.

6.7   Lien Searches.  The Bank shall have received certified responses to
UCC  lien search requests reflecting that there are no effective UCC
financing statements  on file in any filing office in the State of Oklahoma
or any other states or  jurisdictions in which GSC, MA and MSERV maintain
their principal place of business  naming GSC, MA or MSERV as debtor and
covering the Collateral, other than (i)  financing statements in favor of
the Bank, and (ii) financing statements relating to  Permitted Liens.

6.8   Insurance Policies.  The Bank shall have received copies of such
insurance  policies, or binders or certificates of insurance, in form and
substance satisfactory  to the Bank evidencing that GSC, MA and MSERV have
obtained and are maintaining the  minimum insurance coverages required by
the Credit Agreement, as amended by this  Amendment.

6.9   Other Matters.  The Borrowers shall have provided the Bank with such 
reports, information, financial statements, and other documents as the Bank
has  reasonably requested to evidence the Borrowers' compliance with the
terms and  conditions of this Agreement and the Loan Documents.

6.10  Legal Matters.  All legal matters incident to the Loan Documents and 
the Credit Facilities shall be satisfactory to the Bank and its counsel.

6.11  No Defaults.  There shall not have occurred and be continuing any
Default  or Event of Default.

7.    REPRESENTATIONS AND WARRANTIES.  All representations and warranties
of the Borrowers contained in Section 5 of the Credit Agreement are hereby
remade and  restated as the date hereof and shall survive the execution and
delivery of this  Amendment.  The Borrowers (including GSC, MA and MSERV)
further represent and warrant  to the Bank that:

7.1   Authority.  The Borrowers have all corporate power and authority and
have  been duly authorized to execute, deliver and perform its obligations
under this  Amendment, the Credit Agreement (as amended by this Amendment),
and Acquisition Note.

7.2   Binding Obligations; Enforceability.  This Amendment, the Credit
Agreement  (as amended by this Amendment), and each of the Notes are valid
and legally binding  obligations of the Borrowers (including GSC, MA and
MSERV), enforceable in accordance  with their respective terms, except as
limited by applicable bankruptcy, insolvency  or other laws affecting the
enforcement of creditors' rights generally.

7.3   No Conflicts.  The execution, delivery and performance of this
Amendment,  the Credit Agreement (as amended by this Amendment), and the
Acquisition Note by the  Borrowers do not and will not (a) conflict with,
result in a breach of the terms,  conditions or provisions of, constitute a
default under, or result in any violation  of the Borrowers' Certificates
of Incorporation, as amended, or Bylaws, or any  agreement, instrument,
undertaking, judgment, decree, order, writ, injunction,  statute, law, rule
or regulation to which either of the Borrowers is subject or by  which the
assets of either of the Borrowers are bound or affected, (b) result in the 
creation or imposition of any lien, charge or encumbrance on, or security
interest  in, any property now or hereafter owned by the Borrowers,
pursuant to the provisions  of any mortgage, indenture, security agreement,
contract, undertaking or other  agreement to which either of the Borrowers
is a party, other than the obligations of  the Borrowers in favor of the
Bank created by the Loan Documents, or (c) require any  authorization,
consent, license, approval or authorization of, or other action by,  notice
or declaration to, registration with, any court or any administrative or 
governmental body (domestic or foreign), or, to the extent any such consent
or other  action may be required, it has been validly procured or duly
taken.

7.4   No Subsidiaries.  Each of MA and MSERV is a wholly-owned Subsidiary
of GSC.   Except for the foregoing ownership interests of GSC in MA and
MSERV, none of GSC, MA  or MSERV (i) has any Subsidiaries, (ii) owns any
stock in any other corporation, or  (iii) is a partner or joint venturer in
or equity owner of any partnership, joint  venture or other business
association.

8.    MISCELLANEOUS.

8.1   Effect of Amendment.  Except as expressly modified and amended by
this  Amendment, all other terms of the Credit Agreement shall continue in
full force and  effect in accordance with their original stated terms and
are hereby reaffirmed in  every respect as of the date hereof.  To the
extent that the terms of this Amendment  are inconsistent with the terms of
the Credit Agreement, this Amendment shall control  and the Credit
Agreement shall be amended, modified or supplemented so as to give  full
effect to the transactions contemplated by this Amendment.

8.2   Exhibits.  (a)  The form of Acquisition Note attached hereto as
Exhibit "I"  is hereby added as an Exhibit to the Credit Agreement, (b) the
form of Replacement  Revolving Note attached hereto as Exhibit "A-1" is
hereby substituted for Exhibit "A"  to the Credit Agreement, and (c) the
form of Replacement Term Note attached hereto as  Exhibit "B-1" is hereby
substituted for Exhibit "B" to the Credit Agreement.

8.3   Descriptive Headings.  The descriptive headings of the several
paragraphs  of this Amendment are inserted for convenience only and shall
not be used in the  construction or the content of this Amendment.
8.4   Reimbursement of Expenses.  The Borrowers agree to pay all reasonable 
out-of-pocket expenses, including, without limitation, filing fees,
recording costs  and reasonable attorney's fees and expenses, incurred by
the Bank in connection with  the preparation of this Amendment and the
documents contemplated hereby.

8.5   Reaffirmation of Security Agreements.  By signing below, the
Borrowers  hereby ratify and reaffirm the Security Agreements and agree
that the Security  Agreements shall continue in full force and effect in
accordance with their terms as  security for payment and performance of all
Indebtedness arising under or in  connection with the Credit Agreement (as
amended hereby), including, without  limitation, all Indebtedness arising
under, in connection with or evidenced by  Acquisition Note.  All
references to the term "Indebtedness" contained in the Credit  Agreement,
the Security Agreements and other Loan Documents shall hereafter be deemed 
to include all liabilities, obligations and indebtedness of the Borrowers
to the Bank  arising out of or relating to this Amendment or the
Acquisition Note and any and all  extensions and renewals thereof.

IN WITNESS WHEREOF, the Borrowers and the Bank have caused this Agreement
to be  duly executed in multiple counterparts, each of which shall be
considered an  original, effective the date and year first above written.

MATRIX SERVICE COMPANY,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



MATRIX SERVICE, INC.,
an Oklahoma corporation

  
By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary




MIDWEST INDUSTRIAL CONTRACTORS, INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



MATRIX SERVICE MID-CONTINENT, INC.,
an Oklahoma corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary


PETROTANK EQUIPMENT, INC.,
an Oklahoma corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary


TANK SUPPLY, INC.,
an Oklahoma corporation

  
By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



SAN LUIS TANK PIPING CONSTRUCTION CO., INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



COLT CONSTRUCTION CO., INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



MIDWEST INTERNATIONAL, INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



GEORGIA STEEL ACQUISITION CORPORATION,
an Oklahoma corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



GEORGIA STEEL FABRICATORS, INC.,
a Georgia corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



BROWN STEEL CONTRACTORS, INC.,
a Georgia corporation



By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



WEST COAST INDUSTRIAL COATINGS, INC.,
a California corporation



By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



MIDWEST SERVICE COMPANY,
a Delaware corporation



By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



HEATH ENGINEERING, LTD.,
an Ontario corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary


HEATH (TANK MAINTENANCE) ENGINEERING, LTD.,
an United Kingdom corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



MAYFLOWER VAPOR SEAL CORPORATION,
an Oklahoma corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



GENERAL SERVICE CORPORATION,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary


MAINSERVE-ALLENTECH, INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary


MAINTENANCE SERVICES, INC.,
a Delaware corporation


By:      /s/C. William Lee
         ----------------- 
Name:    C. William Lee
Title:   Secretary



LIBERTY BANK AND TRUST COMPANY
OF TULSA, NATIONAL ASSOCIATION


By:     /s/Kevin C. Short
        ----------------- 
Name:   Kevin C. Short
Title:  Banking Officer

      EXHIBITS

Exhibit "A-1"   -   Form of Replacement Revolving Note

Exhibit "B-2"   -   Form of Replacement Term Note

Exhibit "J"     -   Form of Acquisition Note