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                                                                   Exhibit 10.43

           AMENDMENT NO. 3 TO RUST INTERCORPORATE SERVICES AGREEMENT


    This Amendment No. 3 (the "Amendment") to that certain Rust Intercorporate
Services Agreement (the "Services Agreement") dated as of January 1, 1993 by and
among WMX Technologies, Inc. (formerly known as Waste Management, Inc.) ("WMX"),
Chemical Waste Management, Inc. ("CWM"), Wheelabrator Technologies Inc. ("WTI")
and Rust International Inc. ("Rust" or the "Company"), all Delaware
corporations, is made as of December 31, 1995 by and among WMX, CWM, WTI and
Rust.


                                    RECITALS
                                    --------


    WHEREAS, WMX, CWM, WTI and Rust desire to amend the Services Agreement in
order for WMX and its Subsidiaries to provide additional services in connection
with the management of Rust Industrial Services Inc. ("RIS"), a wholly owned
subsidiary of Rust, as set forth herein; and

    WHEREAS, WMX, CWM, WTI and Rust desire to alter the administrative
arrangements which apply to the employee benefit and welfare plans (other than
stock option plans) referred to in the Services Agreement to reflect
organizational changes in Rust;

    NOW, THEREFORE, in consideration of the mutual promises herein set forth and
other good and valuable consideration, the receipt of which is hereby
acknowledged, the parties hereby agree as follows:


                                   AGREEMENTS
                                   ----------

    1. RIS Services. Section 2(f) is added to the Services Agreement to read in
its entirety as follows:

    "(f)  RIS Services.  WMX shall cause its Subsidiaries to operate and manage
    the business of RIS in a reasonable and prudent manner and in accordance
    with all applicable statutes, regulations, ordinances, rules, governmental
    consent agreements and orders, as well as such policies and procedures
    applicable to scaffolding services, industrial cleaning services, and
    utility services as may be adopted from time to time by Rust or RIS,
    subject to such exceptions or modifications thereto as Rust or RIS and WMX
    may from time to time agree upon.  All capital and other expenditures
    incurred with respect to the business of RIS shall be for the account of
    RIS and shall be subject to approval by RIS in accordance with the
    procedures which shall be established by RIS.  Notwithstanding the
    provisions of Section 9 of the Services Agreement, for providing such
    operation and management services to RIS, WMX and its Subsidiaries shall be
    allowed to allocate regional and corporate overhead to RIS on a basis no
    less favorable than the basis on which WMX and its Subsidiaries allocate
    such overhead to their other, wholly owned operating units."

    2.   Employee Benefits and Benefit Services.  Section 6 of the Services
Agreement is hereby amended to read in its entirety as follows:

         "6.  Employee Benefits and Payroll and Benefit Services by the
    Company.  (a)  Responsibility for Savings and Retirement Plan.  With
    respect to the Wheelabrator-Rust Savings and Retirement Plan jointly
    sponsored by the Company and WTI, the Company shall be responsible for all
    claims incurred under such plan and all contributions required by the terms
    of such plan with respect
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    to employees of the Company or any of its Subsidiaries and WTI shall be
    responsible for all claims incurred under such plan and all contributions
    required by the terms of such plan with respect to employees of WTI or any
    of its Subsidiaries.  If in the future WTI or any of its Subsidiaries
    establishes one or more savings and retirement plans for the benefit of its
    and its Subsidiaries' employees, the Company shall cause the trustees of
    the Savings and Retirement Plan to transfer to the trustees of such WTI
    retirement plan or plans cash, securities or other property, or a
    combination thereof, as determined by the Company, subject to approval by
    WTI (which shall not be unreasonably withheld), in an amount equal to the
    aggregate account balance of WTI's and its Subsidiaries' affected present
    or former employees (other than present or former employees of the Company
    or its Subsidiaries) as of the date of the transfer.

         "(b) Benefits Administration. WTI shall be solely responsible for the
    administration of employee benefit plans sponsored by WTI or any of its
    Subsidiaries ("WTI Plans"). However, if requested by WTI, WMX shall cause
    its Subsidiaries to provide to WTI and its Subsidiaries benefits
    administrative services with respect to such WTI Plans, including without
    limitation:

         (i)   record keeping;

         (ii)  employee enrollment and termination;

         (iii) claims and payout administration and processing;

         (iv)  ERISA and other legal and regulatory compliance;

         (v)   Internal Revenue Service reporting;

         (vi)  employee communication; and

         (vii) preparation of reports.

    Further, WMX agrees to cause its Subsidiaries to provide to WTI and its
    Subsidiaries such benefits administrative services with respect to the
    portion of any employee benefit plan sponsored by WMX or its Subsidiaries
    which benefits employees of WTI or its Subsidiaries. For any such services
    WTI shall pay to WMX or its Subsidiaries each calendar quarter during the
    term of this Agreement, within 30 days after being notified of the amount
    due, a quarterly fee equal to WTI's portion of WMX's costs and third party
    charges or expenses related to administration of such plans, which portion
    shall be the arithmetic average of the monthly percentages for the three
    months of such quarter of all employees of all participating employers
    eligible (or who would be eligible, but for the applicable waiting period)
    to participate as of the end of each such month in the plan who were present
    or former employees of WTI or its Subsidiaries as of the end of each month
    (other than present or former employees of WMX or its Subsidiaries).

         "(c) Separate Reports. To the extent legally required, benefits
    administrative services to be provided by the Company, WMX or their
    Subsidiaries shall be performed with respect to employees of WTI and its
    Subsidiaries as a group separate and apart from employees of the Company,
    WMX and their Subsidiaries. To the extent practicable, all reports
    pertaining to benefits and benefit and welfare programs shall also be
    prepared for employees of WTI and its Subsidiaries as a group separate and
    apart from the Company, WMX and their Subsidiaries.

         "(d) Review of Method of Allocation. Promptly after the end of each
    year ending after the Effective Date, WMX and WTI shall review the method
    set forth in Section 6(b) above for WTI's paying
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    charges, expenses or allocations and shall make such changes in such method
    as are necessary or appropriate to ensure that the charges, fees or
    allocations borne by WTI are proportionate to the services provided by WMX
    or its Subsidiaries to WTI pursuant to this Section 6."

    3.   Other Provisions.  Except as expressly set forth in this Amendment,
all provisions of the Services Agreement in effect immediately prior to the
execution and delivery of this Amendment shall remain in full force and effect
in accordance with their terms.

    4.   Choice of Law.  This Amendment shall be interpreted and construed in
accordance with the internal laws (and not the conflicts laws rules) of the
State of Illinois applicable to contracts made and to be performed in the State
of Illinois.

IN WITNESS WHEREOF, the parties have duly executed this Agreement as of the date
first above written.

                                 RUST INTERNATIONAL INC.

                                 By:           /s/ Jan Stern Reed
                                      ----------------------------------------
                                 Name:   Jan Stern Reed
                                 Title:  Assistant Secretary


                                 WMX TECHNOLOGIES, INC.

                                 By:           /s/ Thomas A. Witt
                                      ----------------------------------------
                                 Name:   Thomas A. Witt
                                 Title:  Vice President
 

                                 CHEMICAL WASTE MANAGEMENT, INC.

                                 By:           /s/ Thomas A. Witt
                                      ----------------------------------------
                                 Name:   Thomas A. Witt
                                 Title:  Secretary


                                 WHEELABRATOR TECHNOLOGIES INC.

                                 By:           /s/ Herbert A. Getz
                                      ----------------------------------------
                                 Name:   Herbert A. Getz
                                 Title:  Secretary