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                                                                 Exhibit - 10.57


Summary Plan Description

To:         Long-Term Incentive Compensation Plan Participants

From:       A. P. Pajak

Date:       September 14, 1999

Re:         SUMMARY PLAN DESCRIPTION

            LONG-TERM INCENTIVE COMPENSATION PLAN OF FYE 2000-2002


1     Introduction

The purpose of the Long-Term Incentive Compensation Plan of FYE 2000-2002 (the
"Plan") is to encourage and enable executives, officers and key employees of GZA
GeoEnvironmental Technologies, Inc. (the "Company") and its Subsidiaries and
other persons to acquire a direct stake in the Company's welfare. Promoting
closer identification of these individuals' personal interests with those of the
Company and its shareholders is expected to stimulate their efforts on the
Company's behalf and strengthen their desire to remain with the Company. The
Plan focuses on achieving financial goals set forth in the Company's long-term
Strategic Plan.


2     Plan Summary

2.1     Overview

Upon selection to participate in the Plan, each designated "Participant" will be
assigned a Target Award that represents the amount of Plan compensation that is
expected to be paid to a Participant if certain pre-established financial goals
("Performance Objectives") are fully met. The Target Award will be calculated by
multiplying the Participant's base salary (inclusive of pre-tax deductions for
401(k) deferral and benefits deductions but exclusive of any bonus payments made
during the Plan Period under either the Annual or Long-Term Plans or any special
compensation) earned during the initial year of the Plan by a Target Award
Percentage. Groups of Participants' awards may be adjusted to yield uniform
Target Awards for common classes of Participants in the Plan.


2.2     Eligibility

a)   Eligibility to participate in the Plan is limited to individuals who are
     executives, managers and key employees of the Company whose duties and
     responsibilities provide them the opportunity to (i) make a material and
     significant impact on the financial performance of the Company, (ii) have
     major responsibility in the control of the corporate assets, and (iii)
     provide critical staff support necessary to enhance operating
     profitability.

b)   Eligibility and designated levels of participation will be determined by
     the CEO subject to Committee approval as described below. The fixing of
     eligibility and level of participation shall not create any vested right in
     any Participant to receive a bonus hereunder.



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2.3     Administration

a)   The Compensation Committee, or such other Committee of the Board of
     Directors designated by the Board, shall administer the Plan. The
     administration of the Plan shall include the power to:

         i)     Approve Participants participation in the Plan

         ii)    Establish Performance Goals

         iii)   Determine if and when any Bonuses shall be paid

         iv)    Pay out any Bonuses, in cash, Stock, or stock options, or a
                combination thereof, as the Committee shall determine from
                time to time

         v)     Approve the amount, the form, performance targets, and all other
                particulars of awards under the Plan

         vi)    If deemed appropriate, adjust targets or payments to reflect
                special achievements to which no bonus would, by strictest
                adherence to the Plan, be due or to adjust actual results to
                be used for bonus performance measures in the event of
                one-time-only or unusual charges or additions to earnings,
                such as special write-offs or extraordinary gains

         vii)   Impose and change, from time to time, the maximum amounts or
                percentages payable under the Plan

         viii)  Construe and interpret the Plan

         ix)    Establish rules and regulations and to perform all other acts
                it believes reasonable and proper, including the authority to
                delegate responsibilities to others to assist in administering
                the Plan.

b)   Until such time as the Committee makes a determination to make payment of
     the incentive compensation hereunder with respect to the actual results
     compared to the Performance Goals for any Plan Period, no Participant shall
     have any vested right to receive any amount that might be calculated as
     payable pursuant to the Plan. Furthermore, for any Plan Period and up until
     the Payment Date, the Committee may cancel any Bonuses awarded under the
     Plan if a Participant conducts himself or herself in a manner that the
     Committee determines to be inimical to the best interests of the Company.

c)   Any decision made or action taken by the Committee arising out of or in
     connection with the interpretation and administration of the Plan shall be
     final and conclusive.

d)   If any statute, rule or government regulation or any related compensation
     plan of the Company requires ratification of the Committee's action, the
     Committee will submit its recommendation to the Board for such
     ratification.


2.4     Form of Award

The Target Award will be delivered in three forms:

         o      Cash Performance Awards that will be paid following the Plan
                Period if the EBIBT reported to the stockholders meets or
                exceeds the earnings goal approved by the Committee.

         o      Incentive and Non-Qualified Stock Options that will deliver
                reward to the extent that the market value of the Company's
                stock increases due to achievement of the Strategic Plan goals

The percentage of Target Award assigned to stock options and to cash will be
determined by the Committee.






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2.5      Value of ICP Awards


2.5.1    STOCK OPTIONS

Stock options will be issued pursuant to a current Stock Incentive Plan approved
by the Stockholders of the Company at the time a Participant is selected to
participate in the Plan. The projected value of stock option awards will be
based on the current market value and the expected market value of the Company's
shares at the end of the Plan Period based on projected earnings of the Company
at the end of the Plan Period and anticipated price/earnings ratio. Stock option
vesting may be step or cliff but will be determined at the time of grant
irrespective of future stock price or other performance parameter. Early vesting
may be provided if target measures are reached prior to the end of the Plan
Period. There is no guarantee that the share price will reach the projected
value even if the projected earnings per share is reached. There is no guarantee
that the expected level of compensation will be realized from the stock options.


2.5.2    CASH PERFORMANCE AWARDS

Cash Performance Awards will be made based on achieving the cumulative earnings
goal over the Plan Period. The goal will be based on projected earnings before
bonus, interest and taxes (EBIBT) from the current Five-year Strategic Plan plus
such additional earnings necessary to fund the Cash Performance Awards. The cash
awards will be paid in full if the target cumulative earnings are achieved over
the period of the Plan. Individual year earnings achievements will be ignored
for the purpose of Plan goals. No payment will be made if the achieved
cumulative earnings do not meet or exceed the target earnings. Payments will be
made irrespective of the market price of the Company's shares. The performance
goal for the current Plan Period is defined in Exhibit A.


2.6     TERMINATION OF EMPLOYMENT

In the event a Participant ceases to be employed by the Company:

a) Due to normal retirement, or early retirement with Committee consent, under a
formal plan or policy of the Company, or total and permanent disability, as
determined by the Committee, or death, a Participant's eligibility shall
continue to remain in effect for the duration of the Plan Period. In the event
of such a termination of employment, the Participant, or her or his Beneficiary,
on the Payment Date, shall receive the Participant's portion of the Cash
Performance Award for the applicable Plan Period, adjusted by the Committee in
its sole discretion, pro rata, for the Participant's shortened participation.

b) In the event that a Participant shall cease to be an employee of the Company
upon the occurrence of any other event, the Participant's eligibility under the
Plan shall be canceled and terminated forthwith, and no Bonuses shall be payable
under the Plan except as and to the extent the Committee may determine
otherwise.

c) For purposes of the preceding, it shall not be considered a termination of
employment when a Participant is placed by the Company on military or sick leave
or such other type of leave of absence, for a period of six months or less, that
is considered as continuing intact the employment relationship of the
Participant. For any such leave extending beyond six months, the Committee shall
decide whether and when there has been a termination of employment.

d) Disposition of stock options and restricted stock awarded under this Plan,
subsequent to termination, will be determined by the provisions of the Stock
Incentive Plan under which such options or shares have been issued.





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2.7      ADJUSTMENTS

If there shall be any change in the Stock subject to the Plan through merger,
consolidation, reorganization, recapitalization, stock dividend, stock split,
exchange of stock or other change in the corporate structure, appropriate
adjustments shall be made in the aggregate number and kind of shares subject to
the Plan to reflect such changes, if and to the extent determined by the
Committee, whose determination shall be conclusive. Such adjustments shall be
made in accordance with the Stock Incentive Plan under which the shares were
issued.


2.8     AMENDMENT AND TERMINATION OF PLAN

The Board may, at any time, and from time to time, suspend or terminate the Plan
in whole or in part or amend it from time to time in such respects as the Board
may deem appropriate and in the best interests of the Company.


3    Miscellaneous

a)   GOVERNMENT AND OTHER REGULATIONS: The obligation of the Company to issue,
     or transfer and deliver shares for Bonuses under the Plan shall be subject
     to all applicable laws, regulations, rules and orders that shall then be in
     effect.

b)   UNFUNDED PLAN: The Plan, insofar as it provides for payments, shall be
     unfunded, and the Company shall not be required to segregate any assets
     that may at any time be subject to Bonuses under the Plan. Any liability of
     the Company to any person with respect to any award under this Plan shall
     be based solely upon contractual obligations that may be created under this
     Plan.

c)   RIGHT TO CONTINUED EMPLOYMENT: No person shall have any claim or right to
     be granted a Bonus under the Plan, and the grant of a Bonus under the Plan
     shall not be construed as giving any Participant the right to be retained
     in the employ of the Company, and the Company expressly reserves the right
     at any time to dismiss a Participant with or without cause, free from any
     liability, or any claim under the Plan.

d)   NON-TRANSFERABILITY: Except by will or the laws of descent and
     distribution, no right or interest of any Participant in the Plan shall be
     assignable or transferable and no right or interest of any Participant
     shall be liable for, or subject to, any lien, obligation or liability of
     such Participant.

e)   WITHHOLDING: The Company shall have the right to withhold from cash
     payments sufficient amounts to cover tax withholding for income and
     employment taxes, and if the amount of cash payment is insufficient, the
     Company may require the Participant to pay to it the balance required to be
     withheld. Likewise, the Company may require a payment by the Participant to
     cover applicable withholding for income and employment taxes in the event
     any part of the Bonus is paid in Stock.

f)   PLAN EXPENSES: Any expenses of administering this Plan shall be borne by
     the Company.

g)   LEGAL CONSIDERATIONS: No persons, including a Participant, or his or her
     Beneficiary, shall have any claim or right to the payment of an award, if,
     in the opinion of counsel for the Company, such payment does not comply
     with legal requirements or is opposed to governmental public policy.

h)   OTHER PLANS: Nothing contained herein shall prevent the Company from
     establishing other incentive and benefit plans in which Participants in the
     Plan may also participate. However, any amounts paid to a Participant with
     respect to Bonuses under the Plan shall not affect the level of benefits
     provided to or received by any Participant (or his or her estate or
     Beneficiary) as part of any other employee benefit plan of the Company.

i)   NO WARRANTY OF TAX EFFECT: No opinion shall be deemed to be expressed or
     warranties made as to the effect for federal, state or local tax purposes
     of any Bonuses.




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j)   CONSTRUCTION OF PLAN: The place of administration of the Plan shall be in
     the Commonwealth of Massachusetts, and the validity, construction,
     interpretation, administration and effect of the Plan and of its rules and
     regulations, and rights relating to the Plan, shall be determined solely in
     accordance with the laws of the Commonwealth of Massachusetts.


4     Implementation

         a)     The CEO will develop a Schedule of Participants Awards (the
                "Schedule", Exhibit A), detailing Participants and levels of
                long-term incentive compensation as a function of base salary
                and target performance measures for and adoption by the
                Compensation Committee.

         b)     The Committee will present a motion to the Board for award of
                stock options to be granted to Participants, including numbers
                of shares, vesting and exercise period and other terms based on
                a recommendation prepared by the CEO.

         c)     The Committee will authorize the CEO to grant Cash Performance
                Awards pursuant to the amounts set forth in the approved
                schedule subject to the conditions set forth in the plan
                prepared by the CEO.




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