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                                                                    EXHIBIT 10.9

                                AMENDMENT NO.5

                                       TO

                  CORPORATE REVOLVING AND TERM LOAN AGREEMENT

     Manufacturers and Traders Trust Company (the "Bank") and C.H. Heist Corp. 
(the "Borrower") hereby agree as follows:

     1.   Loan Agreement.  The Bank and the Borrower are parties to a Corporate 
Revolving and Term Loan Agreement dated December 23, 1993, and as amended (the 
"Loan Agreement").  The Bank and the Borrower wish to amend the Loan Agreement 
as set forth herein.

     2.   Amendment to Loan Agreement.  The Bank and the Borrower hereby agree 
that the Loan Agreement is amended as follows:

          a.   Section 2.(i) of the Loan Agreement is modified to read in 
entirety as follows:  "Compensating balances may, but need not, be maintained 
by the Borrower with the Bank with respect to all Revolving Loans.  Such 
compensating balances shall be unrestricted as to use at any time."

          b.   Section 11.dd(i) of the Loan Agreement, as previously amended, 
is modified so that the reference to "August 1, 1999" is deleted and "August 1, 
2000" is substituted in its place.

     3.   Except as expressly modified herein, the Loan Agreement otherwise 
remains unchanged and the Borrower hereby ratifies and reaffirms the Loan 
Agreement, as amended, and  any other documents executed in connection 
therewith, and agrees that the Loan Agreement and all documents executed in 
connection herewith are in full force and effect and fully enforceable with 
their terms and not subject to any offset, claim, counterclaim or defense.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment No. 5 to 
be duly executed by their authorized officers as of the 1st day of July, 1998.


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<S>                                     <C>
C. H. HEIST CORP.                       MANUFACTURERS AND TRADERS
                                        TRUST COMPANY


By: /s/ John L. Rowley                  By:  /s/ Kevin B. Quinn
    ----------------------                   -----------------------
    John L. Rowley                           Kevin B. Quinn
    Vice President and                       Assistant Vice President
    Chief Financial Officer 

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