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                                                                   EXHIBIT 10.24

                      Amendment to Asset Purchase Agreement

                  This First Amendment to the Asset Purchase Agreement (this
"Amendment") is entered into on this 13th day of March, 2000, by and among HMT
Inc., a Delaware corporation ("Buyer"), ITEQ, Inc., a Delaware corporation
("Parent"), ITEQ Storage Systems, Inc., a Minnesota corporation ("ITEQ
Storage"), ITEQ Construction Services, Inc., a Delaware corporation ("ITEQ
Construction") and ITEQ Tank Services, Inc., a Delaware corporation ("ITEQ
Tank"), pursuant to that certain Asset Purchase Agreement (the "Agreement"),
dated as of January 28, 2000. As used herein, ITEQ Storage, ITEQ Construction
and ITEQ Tank are hereinafter sometimes referred to individually as a "Seller"
and collectively as the "Sellers".

                                   Background

                  1. Pursuant to Section 5.3(iv) of the Agreement, subject to
the other terms and conditions therein, the Buyer, on the one hand, or Parent
and Sellers on the other hand, may terminate the Agreement in the event that
Closing shall not have occurred prior to March 13, 2000 (the "Termination
Date").

                  2. Buyer, Parent and Sellers agree that an extension of the
Termination Date is to the mutual benefit of both parties and that an extension
of the Closing is warranted.

                  3. All capitalized terms used and not otherwise defined herein
shall have their respective meaning provided in the Agreement

                                      Terms

                  In consideration of the mutual covenants contained herein and
intending to be legally bound hereby, the parties hereto agree as follows:

                  1. Section 5.1(i) of the Agreement shall be amended in its
entirety as follows:

                  (i) Good Standing Certificate of Sellers. Each Seller shall
have delivered to Buyer a certificate of good standing dated not earlier than
March 3, 2000, certifying that such Seller is a corporation in good standing in
each jurisdiction set forth in Section 2.2 of the Disclosure Letter.

                  2. Section 5.3(a)(iv) of the Agreement shall be amended in its
entirety as follows:

                  (iv) By Buyer, on the one hand or Parent and Sellers, on the
other hand, if Closing shall not have occurred on or prior to March 17, 2000
(the "Termination Date"), provided, that Buyer or Parent may terminate this
Agreement pursuant to this subparagraph (iv) only if Closing shall not have
occurred by such date for a reason other than a material breach by such party of
any of the provisions hereunder.


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                  3. This Amendment shall be governed by and construed and
enforced in accordance with the internal laws (as opposed to the conflicts of
laws provisions) of the State of New York. This Amendment may be executed in any
number of counterparts with the same effect as if the signatures thereto were
upon one instrument. Except as amended hereby, the Parties acknowledge and agree
that the Agreement shall remain in full force and effect, and the Parties hereby
ratify, confirm and adopt the Agreement, as amended hereby.



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         IN WITNESS WHEREOF, the undersigned, intending to be legally bound,
have executed this Amendment as of the date first written above.


                                    HMT INC.


                                    /s/ Jonathan P. Wendell
                                    --------------------------------------------
                                    Jonathan P. Wendell,
                                    President



                                    ITEQ, INC.


                                    /s/ William P. Reid
                                    --------------------------------------------
                                    William P. Reid,
                                    President and Chief Executive Officer



                                    ITEQ STORAGE SYSTEMS, INC.


                                    /s/ William P. Reid
                                    --------------------------------------------
                                    William P. Reid,
                                    President



                                    ITEQ CONSTRUCTION SERVICES, INC.



                                    /s/ William P. Reid
                                    --------------------------------------------
                                    William P. Reid,
                                    President



                                    ITEQ TANK SERVICES, INC.


                                    /s/ William P. Reid
                                    --------------------------------------------
                                    William P. Reid,
                                    President