Exhibit 2.4

                             SUBORDINATION AGREEMENT
                          (All Indebtedness and Liens)


             Holcroft L.L.C., a Delaware limited liability company of
        Livonia, Michigan ("Borrower") is indebted to the undersigned
        ("Creditor") in the principal sum of Two Million Two Hundred
        Eighteen Thousand Dollars ($2,218,000) evidenced by a promissory
        note dated October 10, 1997 which indebtedness is secured by a
        security interest in the property described in attached Exhibit
        "A", and Creditor is or may become financially interested in
        Borrower and desires to aid Borrower in obtaining or having
        continued financial accommodations, whether by way of loan,
        commitment to loan, discounting of instruments, extensions of
        credit or the obtaining of any other financial aid from Comerica
        Bank (the "Bank"), a Michigan banking corporation of 500 Woodward
        Avenue, Detroit, Michigan 48226.

             In order to induce the Bank to extend or to continue to
        extend financial accommodations to Borrower from time to time,
        whether by way of a loan, commitment to loan, discounting of
        instruments, extension of credit or otherwise and in
        consideration of any of these financial accommodations, Creditor
        agrees as follows:

        1.   Any and all obligations and liabilities of Borrower to
             Creditor, including, without limit, principal and interest,
             whether direct or indirect, absolute or contingent, joint or
             several, secured or unsecured, due or to become due, now
             existing or later arising and whatever the amount and
             however evidenced including, without limit, the debt
             described above but excluding the Receivable Note executed
             by Borrower in favor of Creditor dated as of the date hereof
             in the original principal amount of $657,532.51 (the
             "Subordinated Indebtedness"), are subordinated in right of
             payment to any and all obligations and liabilities of
             Borrower to the Bank, including, without limit, principal
             and interest, whether accrued before or after the filing of
             a petition in bankruptcy or similar insolvency proceeding,
             and whether direct or indirect, absolute or contingent,
             joint or several, secured or unsecured, due or to become
             due, now existing or later arising and however evidenced,
             together with all other sums due thereon and all costs of
             collecting the same (including, without limit, reasonable
             attorney fees) for which Borrower is liable (the "Senior
             Indebtedness").

        2.(a)Borrower may not make and Creditor may not receive (by way
             of voluntary payment, set-off, counterclaim or otherwise)
             any payment of principal, interest or any other any other
             amount due with respect to the Subordinated Indebtedness, if
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             at the time of such payment Creditor shall have received a
             notice from Bank of the occurrence of a default with respect
             to the Senior Indebtedness ("Default Notice"). Borrower may
             resume payments (and may make any payments missed due to
             application of the foregoing) and Creditor may receive such
             payments in respect of the Subordinated Indebtedness upon
             the earlier of (a) the cure or written waiver by Bank of
             such default or (b) 180 days shall have elapsed since the
             date the Default Notice was received by Creditor. In no
             event may Borrower make or Creditor receive any prepayment
             of the Subordinated Indebtedness without the consent of
             Bank, which consent may be withheld in the Bank's sole
             discretion.

        (b)  Until the Senior Indebtedness is paid in full, Creditor
             shall not, without the prior written consent of Bank, take
             any Collection Action (as defined below) with respect to the
             Subordinated Indebtedness, except as permitted in the
             following sentence. After the passage of one hundred eighty
             (180) days from the occurrence of any payment default with
             respect to the Subordinated Indebtedness if such default
             shall not have been cured or waived within such period, then
             the Creditor may, upon five (5) business days' prior written
             notice to Bank accelerate the Subordinated Indebtedness or
             take other Collection Action. Such five-day notice may be
             given during the 180-day period described in the preceding
             sentence. Notwithstanding the foregoing, Creditor may file
             proofs of claim against the Borrower in any Proceeding
             involving the Borrower.

             "Collection Action" shall mean (a) to demand, sue for,
             take or receive from or on behalf of the Borrower, by
             set-off or in any other manner, the whole or any part
             of any moneys which may now or hereafter be owing by
             the Borrower with respect to the Subordinated
             Indebtedness, (b) to initiate or participate with
             others in any suit, action or proceeding against the
             Borrower to (i) enforce payment of or to collect the
             whole or any part of the Subordinated Indebtedness or
             (ii) commence judicial enforcement of any of the rights
             and remedies under the documents executed with respect
             to the Subordinated Indebtedness or applicable  law
             with respect to the Subordinated Indebtedness or the
             documents executed in connection with the Subordinated
             Indebtedness, or (c) to accelerate any Subordinated
             Indebtedness.

        (c)  Creditor shall not amend or modify any of the documents
             evidencing or relating to the Subordinated Indebtedness
             without the consent of Bank.

        3.   All rights of Creditor in any collateral now or later
             securing the Subordinated Indebtedness are subordinated to
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             all rights of the Bank now or later existing in any of the
             same collateral securing the Senior Indebtedness. Creditor
             waives all rights to require the Bank to marshall the
             collateral for the Senior Indebtedness or any other property
             the Bank may at any time have as security for the Senior
             Indebtedness and waives all right to require the Bank to
             first proceed against any guarantor or other person before
             proceeding against such collateral. Creditor shall not
             contest the validity, priority or perfection of the Bank's
             security interest in any collateral in which the Creditor
             may also have an interest. The priorities of the Bank and
             the Creditor in such collateral shall be in accordance with
             this Agreement, regardless of whether the Bank's security
             interest or lien in such collateral is valid or perfected.
             Bank may take action to foreclose or otherwise realize upon,
             or protect its interest in, the collateral, in accordance
             with its agreements with the Borrower, at any time, without
             the consent of Creditor, and Creditor agrees not to
             interfere in a manner which would defeat the purpose of this
             Agreement in connection therewith. Bank agrees to provide
             Creditor with notice of such foreclosure or other
             realization upon its collateral. So long as any part of the
             Senior Indebtedness is outstanding, if Bank has agreed to
             release its security interest in any of the collateral in
             connection with the realization of any of its rights with
             respect to such collateral, Bank is hereby authorized as
             Creditor's attorney in fact to execute releases and
             discharges of Creditor's liens and security interests in
             such collateral provided that Bank is releasing or
             discharging Bank's security interest in such collateral as
             part of the same transaction and provided that Bank gives
             Creditor five days prior written notice of such release
             during which such five day period Creditor does not sign and
             deliver to Bank any such releases or discharges.

        4.   In the event of any Proceeding (as defined below) involving
             the Borrower, (a) all Senior Indebtedness first shall be
             paid in full before any payment of or with respect to the
             Subordinated Indebtedness shall be paid; (b) any payment or
             distribution, whether in cash, property or securities which,
             but for the terms hereof, otherwise would be payable or
             deliverable in respect of the Subordinated Indebtedness,
             shall be paid or delivered directly to Bank (to be held
             and/or applied by Bank in accordance with the terms of the
             Senior Indebtedness) until all Senior Indebtedness is paid
             in full; (c) Creditor agrees to execute and deliver to Bank
             or its representative all such further instruments
             reasonable requested by Bank confirming the authorization
             referred to in the foregoing clause (b); and (d) Creditor
             agrees to execute, verify, deliver and file any proofs of
             claim in respect of the Subordinated Indebtedness in
             connection with any such Proceeding and hereby irrevocably
             authorizes, empowers and appoints Bank its agent and
                                        3PAGE

             attorney-in-fact to (i) execute, verify, deliver and file
             such proofs of claim upon the failure of Creditor promptly
             to do so (and, in any event, prior to 10 days before the
             expiration of the time to file any such proof) and (ii) vote
             such claim in any such Proceeding upon the failure of
             Creditor to do so prior to 10 days before the expiration of
             the time to vote and such claim; provided, however, that
             Bank shall have no obligation to execute, verify, deliver,
             file and/or vote any such proof of claim. In the event that
             Bank votes any claim in accordance with the authority
             granted hereby, Creditor shall not be entitled to change or
             withdraw such vote. 

             "Proceeding" shall mean any voluntary or involuntary
             insolvency, bankruptcy, receivership, custodianship,
             liquidation, dissolution, reorganization, assignment
             for the benefit of creditors, appointment of a
             custodian, receiver, trustee or other officer with
             similar powers or any other proceeding for the
             liquidation, dissolution or other winding up of
             Borrower.

        5.   Should any payment, distribution or security or proceeds
             from these be received by Creditor upon or with respect to
             the Subordinated Indebtedness prior to the satisfaction in
             full of the Senior Indebtedness which is not permitted by
             the terms of this Agreement, Creditor shall immediately
             deliver same to the Bank in the form received (except for
             endorsement or assignment by Creditor where required by the
             Bank), for application on the Senior Indebtedness (whether
             or not then due and in such order of maturity as Bank
             elects) and, until so delivered, the same shall be held in
             trust by Creditor as the property of the Bank. In the event
             of the failure of Creditor to make this endorsement or
             assignment and if such failure remains uncured for fifteen
             (15) days following written notice thereof from Bank to
             Creditor, the Bank or any Bank employee is irrevocably
             authorized and appointed as attorney-in-fact for Creditor to
             make the same.

        6.   Creditor represents and warrants that it has not made or
             permitted to be made any assignment or transfer, for
             collateral purposes or otherwise, of the Subordinated
             Indebtedness or any collateral or other security for the
             Subordinated Indebtedness. Creditor shall not make or permit
             any assignment, transfer, pledge or disposition of all or
             any part of the Subordinated Indebtedness or any collateral
             or other security for the Subordinated Indebtedness while
             any Senior Indebtedness remains unpaid except upon five (5)
             days prior written notice to Bank and unless the assignee or
             transferee has agreed in a writing acceptable to the Bank to
             be bound by the terms of this Agreement. Until the Senior
             Indebtedness is paid in full, each instrument evidencing any
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             Subordinated Indebtedness shall at all times contain in a
             conspicuous manner the following legend:

             "This Note and the indebtedness evidenced hereby are
             subordinate in the manner and extent set forth in that
             certain Subordination Agreement dated as of October 10,
             1997 among Thermo Terratech, Inc., Comerica Bank and
             Holcroft L.L.C. to the indebtedness owed by Holcroft
             L.L.C. to Comerica Bank and each holder of this Note,
             by its acceptance hereof, shall be bound by the
             provisions of the Subordination Agreement."

        7.   Possession by the Bank of any note or other evidence of
             indebtedness made, endorsed or guaranteed by Borrower shall
             be conclusive evidence (but not the only means of
             establishing) that Borrower is indebted to the Bank and that
             this indebtedness is covered by this Agreement.

        8.   This Agreement constitutes a continuing agreement of
             subordination and shall remain in full force and effect
             until such time as all of the Senior Indebtedness has been
             paid in full, each commitment on the part of Bank to extend
             credit to Borrower has been terminated and all letters of
             credit issued by Bank for the account of Borrower have
             expired.

        9.   Creditor waives notice of acceptance of this Agreement and
             presentment, demand, protest, notice of protest, dishonor,
             notice of dishonor, notice of default and diligence in
             collecting any Senior Indebtedness, and agrees that the Bank
             may modify the terms of borrowing, compromise, extend,
             increase, accelerate, renew or forbear to enforce payment of
             any part or all of any Senior Indebtedness, or permit
             Borrower to incur additional Senior Indebtedness, all
             without notice to Creditor and without affecting in any
             manner the Bank's rights or Creditor's obligations under
             this Agreement. Creditor further waives any and all other
             notices to which Creditor might otherwise be entitled.
             Creditor acknowledges and agrees that the Bank's rights
             under this Agreement are not conditioned upon pursuit by the
             Bank of any remedy the Bank may have against the Borrower or
             any other person or any other security. The absence of
             Borrower's signature at the end of this Agreement shall in
             no way impair or affect the validity of this Agreement.

        10.  Creditor delivers this Agreement based solely on Creditor's
             independent investigation of (or decision not to
             investigate) the financial condition of the Borrower and is
             not relying on any information furnished by the Bank.
             Creditor assumes full responsibility for obtaining any
             further information concerning the Borrower's financial
             condition, the status of the Senior Indebtedness or any
             other matter which Creditor may deem necessary or
                                        5PAGE

             appropriate now or later. Creditor waives any duty on the
             part of the Bank, and agrees that Creditor is not relying
             upon nor expecting the Bank to disclose to Creditor any fact
             now or later known by the Bank, whether relating to the
             operations or condition of the Borrower, the existence,
             liabilities or financial condition of any guarantor of the
             Senior Indebtedness, the occurrence of any default with
             respect to the Senior Indebtedness, or otherwise,
             notwithstanding any effect such fact may have upon
             Creditor's risk or Creditor's rights against the Borrower.
             Creditor knowingly accepts the full range of risk
             encompassed in this Agreement, which risk includes, without
             limit, the possibility that the Borrower may incur Senior
             Indebtedness to the Bank after the financial condition of
             the Borrower, or its ability to pay Borrower's debts as they
             mature, has deteriorated.

        11.  Creditor represents that: (a) the Bank has made no
             representation to Creditor as to the creditworthiness of the
             Borrower; and (b) Creditor has established adequate means of
             obtaining from the Borrower on a continuing basis financial
             and other information pertaining to the Borrower's financial
             condition. Creditor agrees to keep adequately informed of
             any facts, events, or circumstances which might in any way
             affect the risks of Creditor under this Agreement.

        12.  The Bank, in its sole discretion, without notice to
             Creditor, may release, exchange, enforce and otherwise deal
             with any security now or later held by the Bank for payment
             of the Senior Indebtedness or release any party now or later
             liable for payment of the Senior Indebtedness without
             affecting in any manner the Bank's rights under this
             Agreement. Creditor acknowledges and agrees that the Bank
             has no obligation to acquire or perfect any lien on or
             security interest in any asset(s), whether realty or
             personalty, to secure payment of the Senior Indebtedness.

        13.  If after receipt of any payment of all or any part of the
             Senior Indebtedness, the Bank is for any reason compelled to
             surrender the payment to any person or entity, because the
             payment is determined to be void or voidable as a
             preference, impermissible setoff, diversion of trust funds
             or for any other reason, then to the extent of that payment,
             the Senior Indebtedness shall be automatically revived and
             the Bank's rights under this Agreement shall be
             automatically continued in effect without reduction or
             discharge for that payment, and this Agreement shall
             automatically continue in full force notwithstanding any
             contrary action which may have been taken by the Bank in
             reliance upon that payment (including, without limit,
             surrender or termination of this Agreement) and any contrary
             action so taken shall be without prejudice to the Bank's
             rights under this Agreement and shall be deemed to have been
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             conditioned upon that payment having become final and 
             irrevocable.

        14.  Creditor waives any right to require the Bank to: (a)
             proceed against any person, including without limit the
             Borrower; (b) proceed against or exhaust any security held
             from the Borrower or any other person; (c) pursue any other
             remedy in the Bank's power; or (d) make any presentments or
             demands for performance, or give any notices of
             nonperformance, protests, notices of protest or notices of
             dishonor in connection with any obligations or evidences of
             Senior Indebtedness held by the Bank as security, in
             connection with any other obligations or evidences of Senior
             Indebtedness which continues in whole or in part as the
             Senior Indebtedness, or in connection with the creation of
             new or additional Senior Indebtedness.

        15.  Creditor acknowledges that the Bank has the right to sell,
             assign, transfer, negotiate or grant participations or any
             interest in, any or all of the Senior Indebtedness and any
             related obligations, including without limit this Agreement.

        16.  No waiver or modification of any of its rights under this
             Agreement shall be effective unless the waiver or
             modification shall be in writing and signed by an authorized
             officer on behalf of the Bank, and each waiver or
             modification shall be a waiver or modification only with
             respect to the specific matter to which the waiver or
             modification relates and shall in no way impair the rights
             of the Bank or the obligations of Creditor to the Bank in
             any other respect.

        17.  Creditor waives notice of acceptance by the Bank of this
             Agreement and this Agreement is immediately binding upon
             Creditor.

        18.  This Agreement shall bind and be for the benefit of Creditor
             and the Bank and their respective successors and assigns,
             and shall be construed according to the laws of the State of
             Michigan.

        19.  The term "Borrower", as used in this Agreement, includes any
             person, corporation, partnership or business entity which
             succeeds to the interests or business of the Borrower named
             above, and the terms "Senior Indebtedness" and "Subordinated
             Indebtedness" include indebtedness of any successor Borrower
             to the Bank and Creditor.

        20.  If this Agreement is executed by two or more persons, it
             shall bind each of them individually as well as jointly.

        21.  Creditor agrees to reimburse the Bank for any and all costs
             and expenses (including, without limit, court costs, legal
                                        7PAGE

             fees, and reasonable attorney fees whether inside or outside
             counsel is used, whether or not suit is instituted and, if
             instituted, whether at the trial or appellate level, in a
             bankruptcy, probate or administrative proceeding, or
             otherwise) incurred in enforcing any of the duties and
             obligations of Creditor under this Agreement but only to the
             extent such costs or expenses are incurred as a result of a
             breach by Creditor of the terms and provisions of this
             Agreement which breach remains uncured for fifteen (15) days
             after written notice thereof by Bank to Creditor.

             THE UNDERSIGNED AND THE BANK ACKNOWLEDGE THAT THE RIGHT TO
        TRIAL BY JURY IS A CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED.
        EACH PARTY, AFTER CONSULTING (OR HAVING HAD THE OPPORTUNITY TO
        CONSULT) WITH COUNSEL OF THEIR CHOICE, KNOWINGLY AND VOLUNTARILY,
        AND FOR THEIR MUTUAL BENEFIT, WAIVES ANY RIGHT TO TRIAL BY JURY
        IN THE EVENT OF LITIGATION REGARDING THE PERFORMANCE OR
        ENFORCEMENT OF, OR IN ANY WAY RELATED TO, THIS AGREEMENT.

             IN WITNESS WHEREOF, Creditor has caused this Agreement to be
        executed as of the  10th day of October, 1997.


                                           CREDITOR:

        WITNESS(ES):                       THERMO TERRATECH INC.


        /s/ Cheryl Norden                  /s/ John P. Appleton

        /s/ Christine Leonard              Chief Executive Officer


                                           CREDITOR'S ADDRESS:


                                           81 Wyman Street

                                           Waltham, MA 02254



                                           COMERICA BANK:


                                           /s/ Michael Stapleton

                                           Vice President

                                        8PAGE

                            Borrower's Acknowledgment

             Holcroft L.L.C. ("Borrower"), accepts notice of
        subordination created by this Agreement and agrees that it will
        take no action inconsistent with this Agreement and that, except
        with the prior written approval of Bank, no payment or
        distribution shall be made by Borrower on or with respect to the
        Subordinated Indebtedness, so long as this Agreement remains in
        effect. Borrower agrees that the Bank may, at its option, without
        notice and without limiting Bank's other rights, upon any breach
        by Creditor of, or purported termination by the Creditor of, this
        Agreement, declare all Senior Indebtedness to be immediately due
        and payable and/or terminate any commitments of Bank to Borrower.


                                 BORROWER:

                                           HOLCROFT L.L.C.

                                           By:  Holcroft Technologies
                                                L.P., Sole Member of
                                                Holcroft L.L.C.

                                           By:  Holcroft Management,
                                                Inc., General Partner of
                                                Holcroft  Technologies
                                                L.P.


                                           By: /s/ Scott M. Murray

                                           Its: President


                                           Dated: October 10, 1997
PAGE

                                    EXHIBIT A

             All of the Debtor's now owned or hereafter acquired: (i)
        inventory; (ii) accounts, contract rights, chattel paper,
        documents and instruments; (iii) technology or know-how; (iv)
        other general intangibles, including but not limited to
        trademarks, patent rights, copyrights, goodwill, records,
        computer programs and rights in premises used in the conduct of
        Debtor's business; (v) equipment, including but not limited to
        all vehicles, machinery, tools, furniture and fixtures; and (vi)
        other personal property of every kind, including tax refunds or
        interests in the claims under policies of insurance; and all
        products and proceeds of the foregoing, including insurance
        proceeds.