Exhibit 10.65


                    AMENDMENT NO. 1 TO NOTE, PREFERRED STOCK
                         AND WARRANT PURCHASE AGREEMENT

                          Dated as of December 23, 1997

                                  by and among

                       TANKNOLOGY-NDE INTERNATIONAL, INC.,
              TANKNOLOGY/NDE CORPORATION, 2368692 CANADA, INC., and
             TANKNOLOGY-NDE CONSTRUCTION SERVICES, INC., as Sellers

                                       and

                         DH HOLDINGS CORP., as Purchaser

     This Amendment No. 1 (this "First Amendment") to Note,  Preferred Stock and
Warrant  Purchase  Agreement  dated as of  December  23,  1997  ("Note  Purchase
Agreement")  by and among  Tanknology-NDE  International,  Inc.,  Tanknology/NDE
Corporation,  2368692 Canada, Inc.,  Tanknology-NDE  Construction Services, Inc.
(collectively,  the "Sellers") and DH Holdings  Corp.  ("Purchaser")  is entered
into as of the 10th day of July, 1998.

                              W I T N E S S E T H:

     Sellers  and  Purchaser  desire to amend  the Note  Purchase  Agreement  in
accordance with the terms and conditions set forth herein.

     NOW, THEREFORE, in consideration of the premises herein contained, and each
intending to be legally bound hereby, the parties hereto agree as follows:

          1. Subsection (f)(iii) of Section 10 of the Note Purchase Agreement is
     hereby deleted.

          2. The word "and" is hereby added at the end of  subsection  (f)(i) of
     Section  10 and ";  and"  appearing  at the end of  subsection  (f)(ii)  of
     Section 10 is hereby deleted and a period is substituted therefor.

          3.  This  First  Amendment  shall  be  governed  by and  construed  in
     accordance with the laws of the State of Delaware.

          4.  Except as amended  hereby,  all terms and  provisions  of the Note
     Purchase Agreement shall remain in full force and effect.


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          5. This First Amendment may be executed in multiple counterparts, each
     of  which  shall  be  deemed  to be an  original  and  all of  which  shall
     constitute one and the same agreement.

     The Parties have caused this First  Amendment to be executed and  delivered
effective as of the date first above written.

                                             Sellers:

                                             TANKNOLOGY-NDE INTERNATIONAL, INC.


                                             By:    //s// JAY ALLEN CHAFFEE
                                                  ----------------------------
                                                  Name:  Jay Allen Chaffee
                                                  Its:  Chairman


                                             PROECO, INC.


                                             By:    //s// JAY ALLEN CHAFFEE
                                                  ----------------------------
                                                  Name:  Jay Allen Chaffee
                                                  Its:  Chairman


                                             TANKNOLOGY/NDE CORPORATION


                                             By:    //s// JAY ALLEN CHAFFEE
                                                  ----------------------------
                                                  Name:  Jay Allen Chaffee
                                                  Its:  Chairman


                                             2368692 CANADA, INC.


                                             By:    //s// JAY ALLEN CHAFFEE
                                                  ----------------------------
                                                  Name:  Jay Allen Chaffee
                                                  Its:  President



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<PAGE>


                                             TANKNOLOGY-NDE CONSTRUCTION
                                             SERVICES, INC.


                                             By:    //s// JAY ALLEN CHAFFEE
                                                  ----------------------------
                                                  Name:  Jay Allen Chaffee
                                                  Its:  Chairman


                                             Purchaser:

                                             DH HOLDINGS CORP.


                                             By:    //s// DANIEL COMAS
                                                  ----------------------------
                                                  Name:  Daniel Comas
                                                  Its:  Vice President


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