Exhibit 10.43
                              THERMO TERRATECH INC.

                    RESTATED STOCK HOLDING ASSISTANCE PLAN


SECTION 1.   Purpose.

      The purpose of this Plan is to benefit Thermo TerraTech Inc. (the
"Company") and its stockholders by encouraging Key Employees to acquire and
maintain share ownership in the Company, by increasing such employees'
proprietary interest in promoting the growth and performance of the Company and
its subsidiaries and by providing for the implementation of the Stock Holding
Policy.

SECTION 2. Definitions.

      The following terms, when used in the Plan, shall have the meanings set
forth below:

      Committee:   The Human Resources Committee of the Board of
Directors of the Company as appointed from time to time.

      Common Stock:   The common stock of the Company and any
successor thereto.

      Company:   Thermo TerraTech Inc., a Delaware corporation.

      Stock Holding Policy:   The Stock Holding Policy of the
Company, as adopted by the Committee and as in effect from time
to time.

      Key Employee: Any employee of the Company or any of its subsidiaries,
including any officer or member of the Board of Directors who is also an
employee, as designated by the Committee, and who, in the judgment of the
Committee, will be in a position to contribute significantly to the attainment
of the Company's strategic goals and long-term growth and prosperity.

      Loans:   Loans extended to Key Employees by the Company
pursuant to this Plan.

      Plan:   Thermo TerraTech Inc. Stock Holding Assistance Plan,
as amended from time to time.

SECTION 3. Administration.

      The Plan and the Stock Holding Policy shall be administered by the
Committee, which shall have authority to interpret the Plan and the Stock
Holding Policy and, subject to their provisions, to prescribe, amend and rescind
any rules and regulations and to make all other determinations necessary or
desirable for the administration thereof. The Committee's interpretations and
decisions with regard to the Plan and the Stock Holding Policy and such rules
and regulations as may be established thereunder shall be final and conclusive.
The Committee may correct any defect or supply any omission or reconcile any
inconsistency in the Plan or the Stock Holding Policy, or in any Loan in the
manner and to the extent the Committee deems desirable to carry it into effect.
No member of the Committee shall be liable for any action or omission in
connection with the Plan or the Stock Holding Policy that is made in good faith.

SECTION 4. Loans and Loan Limits.

      The Committee has determined that the provision of Loans from time to time
to Key Employees in such amounts as to cause such Key Employees to comply with
the Stock Holding Policy is, in the judgment of the Committee, reasonably
expected to benefit the Company and authorizes the Company to extend Loans from
time to time to Key Employees in such amounts as may be requested by such Key
Employees in order to comply with the Stock Holding Policy. Such Loans may be
used solely for the purpose of acquiring Common Stock (other than upon the
exercise of stock options or under employee stock purchase plans) in open market
transactions or from the Company.

      Each Loan shall be full recourse and evidenced by a non-interest bearing
promissory note substantially in the form attached hereto as Exhibit A (the
"Note") and maturing in accordance with the provisions of Section 6 hereof, and
containing such other terms and conditions, which are not inconsistent with the
provisions of the Plan and the Stock Holding Policy, as the Committee shall
determine in its sole and absolute discretion.

SECTION 5. Federal Income Tax Treatment of Loans.

      For federal income tax purposes, interest on Loans shall be imputed on any
interest free Loan extended under the Plan. A Key Employee shall be deemed to
have paid the imputed interest to the Company and the Company shall be deemed to
have paid said imputed interest back to the Key Employee as additional
compensation. The deemed interest payment shall be taxable to the Company as
income, and may be deductible to the Key Employee to the extent allowable under
the rules relating to investment interest. The deemed compensation payment to
the Key Employee shall be taxable to the employee and deductible to the Company,
but shall also be subject to employment taxes such as FICA and FUTA.

SECTION 6. Maturity of Loans.

      Each Loan to a Key Employee hereunder shall be due and payable on demand
by the Company. If no such demand is made, then each Loan shall mature and the
principal thereof shall become due and payable on the fifth anniversary of the
date of the Loan, provided that the Committee may, in its sole and absolute
discretion, authorize such other maturity and repayment schedule as the
Committee may determine. Each Loan shall also become immediately due and payable
in full, without demand, upon the occurrence of any of the events set forth in
the Note; provided that the Committee may, in its sole and absolute discretion,
authorize an extension of the time for repayment of a Loan upon such terms and
conditions as the Committee may determine.

SECTION 7. Amendment and Termination of the Plan.

      The Committee may from time to time alter or amend the Plan or the Stock
Holding Policy in any respect, or terminate the Plan or the Stock Holding Policy
at any time. No such amendment or termination, however, shall alter or otherwise
affect the terms and conditions of any Loan then outstanding to Key Employee
without such Key Employee's written consent, except as otherwise provided herein
or in the promissory note evidencing such Loan.

SECTION 8. Miscellaneous Provisions.

      (a) No employee or other person shall have any claim or right to receive a
Loan under the Plan, and no employee shall have any right to be retained in the
employ of the Company due to his or her participation in the Plan.

      (b) No Loan shall be made hereunder unless counsel for the Company shall
be satisfied that such Loan will be in compliance with applicable federal, state
and local laws.

      (c) The expenses of the Plan shall be borne by the Company.

      (d) The Plan shall be unfunded, and the Company shall not be required to
establish any special or separate fund or to make any other segregation of
assets to assure the making of any Loan under the Plan.

      (e) Except as otherwise provided in Section 7 hereof, by accepting any
Loan under the Plan, each Key Employee shall be conclusively deemed to have
indicated his acceptance and ratification of, and consent to, any action taken
under the Plan or the Stock Holding Policy by the Company, the Board of
Directors of the Company or the Committee.

      (f) The appropriate officers of the Company shall cause to be filed any
reports, returns or other information regarding Loans hereunder, as may be
required by any applicable statute, rule or regulation.

SECTION 9. Effective Date.

      The Plan and the Stock Holding Policy shall become effective upon approval
and adoption by the Committee.


DOC # 1113
TTT STOCK HOLDING ASSISTANCE PLAN



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                         EXHIBIT A TO STOCK HOLDING ASSISTANCE PLAN


                              THERMO TERRATECH INC.
                                 Promissory Note



$---------
Dated:____________


      For value received, ________________, an individual whose residence is
located at _______________________ (the "Employee"), hereby promises to pay to
Thermo TerraTech Inc. (the "Company"), or assigns, ON DEMAND, but in any case on
or before [insert date which is the fifth anniversary of date of issuance] (the
"Maturity Date"), the principal sum of [loan amount in words] ($_______), or
such part thereof as then remains unpaid, without interest. Principal shall be
payable in lawful money of the United States of America, in immediately
available funds, at the principal office of the Company or at such other place
as the Company may designate from time to time in writing to the Employee.

      Unless the Company has already made a demand for payment in full of this
Note, the Employee agrees to repay to the Company from the Employee's annual
cash incentive compensation (referred to as bonus), beginning with the first
such bonus payment to occur after the date of this Note and on each of the next
four bonus payment dates occurring prior to the Maturity Date, such amount as
may be designated by the Company. Any amount remaining unpaid under this Note,
if no demand has been made by the Company, shall be due and payable on the
Maturity Date.

      This Note may be prepaid at any time or from time to time, in whole or in
part, without any premium or penalty. The Employee acknowledges and agrees that
the Company has advanced to the Employee the principal amount of this Note
pursuant to the Company's Stock Holding Assistance Plan, and that all terms and
conditions of such Plan are incorporated herein by reference.

      The unpaid principal amount of this Note shall be and become immediately
due and payable without notice or demand, at the option of the Company, upon the
occurrence of any of the following events:

           (a) the termination of the Employee's employment with the Company,
      with or without cause, for any reason or for no reason;

           (b)  the death or disability of the Employee;

           (c) the failure of the Employee to pay his or her debts as they
      become due, the insolvency of the Employee, the filing by or against the
      Employee of any petition under the United States Bankruptcy Code (or the
      filing of any similar petition under the insolvency law of any
      jurisdiction), or the making by the Employee of an assignment or trust
      mortgage for the benefit of creditors or the appointment of a receiver,
      custodian or similar agent with respect to, or the taking by any such
      person of possession of, any property of the Employee; or

           (d) the issuance of any writ of attachment, by trustee process or
      otherwise, or any restraining order or injunction not removed, repealed or
      dismissed within thirty (30) days of issuance, against or affecting the
      person or property of the Employee or any liability or obligation of the
      Employee to the Company.

      In case any payment herein provided for shall not be paid when due, the
Employee further promises to pay all costs of collection, including all
reasonable attorneys' fees.

      No delay or omission on the part of the Company in exercising any right
hereunder shall operate as a waiver of such right or of any other right of the
Company, nor shall any delay, omission or waiver on any one occasion be deemed a
bar to or waiver of the same or any other right on any future occasion. The
Employee hereby waives presentment, demand, notice of prepayment, protest and
all other demands and notices in connection with the delivery, acceptance,
performance, default or enforcement of this Note. The undersigned hereby assents
to any indulgence and any extension of time for payment of any indebtedness
evidenced hereby granted or permitted by the Company.

      This Note has been made pursuant to the Company's Stock Holding Assistance
Plan and shall be governed by and construed in accordance with, such Plan and
the laws of the State of Delaware and shall have the effect of a sealed
instrument.


                               -------------------------------

                               Employee Name: _________________


------------------------
Witness

DOC # 1113
TTT STOCK HOLDING ASSISTANCE PLAN