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                                                                    EXHIBIT 10.4

                             MEMORANDUM OF AGREEMENT

         THIS MEMORANDUM OF AGREEMENT ("MOA") is entered into this 15th day of
June, 2001 by and between EnviroClean International, Inc. (formerly known as
Advanced EnviroTech Systems, Inc.,) with offices at 12750 Merit Drive-Park
Central VII, Suite 770, Dallas, Texas 75251 (hereinafter "ENVI"), and
Intercontinental Manufacturing Company, a division of Datron, Inc., having an
address at 1200 N. Glenbrook Drive, Garland, Texas 75040 (hereinafter "IMCO").

         WHEREAS, ENVI owns certain intellectual property rights in and to a
solid waste treatment technology marketed under the trade name EnviroClean
Thermal Oxidation System ("TOS"); and

         WHEREAS, ENVI has entered into an arrangement with IMCO wherein ENVI
has granted IMCO the exclusive right to, among other things, market TOS to
certain foreign countries including, without limitation, the Kingdom of Saudi
Arabia; and

         WHEREAS, in consideration for granting such exclusive marketing rights,
ENVI is entitled to receive from IMCO a royalty fee for each TOS sold by IMCO;
and

         WHEREAS, in order to attempt to effect a sale of a quantity of TOS
units to the Kingdom of Saudi Arabia, IMCO deems it necessary to reduce the unit
sales price of TOS below those levels previously contemplated, which action will
also require a reduction to the royalty percentage rate applied to such
contemplated sales; and

         WHEREAS, ENVI is willing to accept a reduced royalty on such sales to
the Kingdom of Saudi Arabia in return for the potential marketing benefits that
could be expected to occur as a result of the market exposure such a sale to the
Kingdom of Saudi Arabia could create; and

         WHEREAS, ENVI owes IMCO for certain expenses incurred by IMCO on ENVI's
behalf and has previously agreed to reimburse IMCO for these amounts owed by, in
part, permitting IMCO to retain portions of any such royalties received from TOS
sales; and

         WHEREAS, ENVI and IMCO desire to amend the manner in which any such
royalty amounts are to be applied to reduce the amounts owed IMCO by ENVI.

         NOW THEREFORE, the parties hereto, in consideration of the foregoing
and of the mutual covenants, agreements and conditions herein contained, do
hereby agree as follows:

         1.    REVISED ROYALTY RATE. ENVI and IMCO hereby agree that, with
               respect to the sale of any TOS units made by IMCO to the
               Kingdom of Saudi Arabia (including, without limitation, any
               persons, firms or entities acting as contractors or agents of
               the Kingdom of Saudi Arabia) during the six (6) month period
               commencing as of the effective date of the MOA, royalties will
               accrue at the flat rate of $25,000 per TOS unit.

         2.    APPLICATION OF ROYALTY AMOUNTS. ENVI and IMCO hereby agree
               that, with respect to the sale of any TOS units made by IMCO
               to the Kingdom of Saudi Arabia (including, without limitation,
               any persons, firms or entities acting as contractors or agents
               of the Kingdom

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               of Saudi Arabia), any royalty amounts applicable to any such
               TOS sales will be applied cumulatively in the following manner;

                   o    First, to reduce that amount owed by ENVI to IMCO and
                        generally referred to as the "contingent accounts
                        payable", in the approximate amount of $400,000.

                   o    Second, applicable royalties up to an amount of $500,000
                        in excess of the "contingent accounts payable amount"
                        will be permanently waived by ENVI as a means to permit
                        IMCO to achieve a reduction in the selling price of
                        TOS units below those levels previously contemplated
                        by IMCO.

                   o    Third, any royalties received in excess of those
                        permanently waived or applied to the "contingent
                        accounts payable" amount (the "excess royalties"), shall
                        be paid to ENVI. In the event that the quantity of TOS
                        units ordered by the Kingdom of Saudi Arabia is
                        sufficient to result in any such "excess royalties",
                        IMCO will use its reasonable best efforts to collect and
                        remit such royalty amounts to ENVI on an accelerated
                        basis.

         3.    CONVERSION OF IMCO ACCOUNTS RECEIVABLE. At present, IMCO has
               on its books an accounts receivable due from ENVI in the
               approximate amount of $600,000. IMCO hereby agrees to accept
               and ENVI agrees to tender to IMCO common stock shares in a
               company named MedSolutions, Inc., a corporation formed or to
               be formed by ENVI, in full satisfaction of the amount of this
               accounts receivable. ENVI and IMCO agree that IMCO shall
               receive a number of shares in MedSolutions, Inc., equal to
               that number derived by dividing the total amount of the
               approximate $600,000 accounts receivable due IMCO by $1.25,
               the anticipated per share price of MedSolutions, Inc. at date
               of initial issuance.

         4.    COMPLETE AGREEMENT. This agreement sets forth the entire
               understanding of the parties with respect to this MOA and
               supersedes all prior agreements, covenants, arrangements,
               communications and representations with respect to this MOA
               and supersedes all prior agreements, covenants, arrangements,
               communications and representations with respect to the subject
               matter of this MOA.

         IN WITNESS WHEREOF, the parties hereto have caused this MOA to be
executed as of the day and year first written above.



INTERCONTINENTAL MANUFACTURING COMPANY       ENVIROCLEAN INTERNATIONAL, INC.

          By:   /s/ S.J. NUZZO               By:   /s/ MATTHEW H. FLEEGER
             -------------------------          -----------------------------
                   S. J. Nuzzo                        Matthew H. Fleeger