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                                                                   Exhibit 10.14

                                                       Employee:  Earl McConchie


                          MOLTEN METAL TECHNOLOGY, INC.
                              EMPLOYMENT AGREEMENT

      IN CONSIDERATION of my employment or the continuance of my employment by
Molten Metal Technology, Inc. or any of its subsidiaries (collectively, the
"Company") and for other valuable consideration, receipt of which is
acknowledged, I agree as follows:

1.    General.

      I agree to use my best efforts, skills and abilities to promote the
interests of the Company, to diligently, competently and faithfully carry out my
duties to the Company in compliance with all Company policies and procedures as
from time to time determined by the Company's Board of Directors. During the
term of any employment by the Company I agree to devote the whole of my business
time and energies to the Company, and to not be involved, directly or
indirectly, in any other business enterprise without the prior written consent
of the Company. I understand I shall be entitled to receive such compensation as
from time to time determined by the Board of Directors, and shall be entitled to
receive such benefits as are normally provided to employees of the Company in
comparable positions. I understand that my employment is on an "at will" basis
and may be terminated at any time by the Board of Directors with or without
cause, and that this Agreement shall not imply that such employment will
continue for any period of time.

2.    Proprietary Information of the Company.

      (a)   I agree that all information and know-how, whether or not in 
writing, of a private, secret, or confidential nature concerning the Company's
business or financial affairs (collectively, "Proprietary Information") is and
shall be the exclusive property of the Company. By way of illustration, but not
limitation, Proprietary Information may include inventions, products, processes,
methods, techniques, formulas, compositions, compounds, projects, developments,
plans, research data, financial data, personnel data, computer programs,
functional specifications and customer and supplier lists. I will not disclose
any Proprietary Information to others outside the Company or use the same for
any unauthorized purposes without written approval by an officer (other than
myself if I am or become an officer) of the Company, either during or after my
employment, unless and until such Proprietary Information has become public
knowledge without fault by me.

      (b)   I agree that all files, letters, memoranda, reports, records, data,
sketches, drawings, laboratory notebooks, program listing, or other written,
photographic, tangible material containing Proprietary Information, whether
created by me or others, which shall come into my custody or possession, shall
be and are the exclusive property of the Company to be used by me only in the
performance of my duties for the Company. All such records or copies thereof and
all tangible

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property of the Company in my custody or possession shall be delivered to the
property of the Company upon the earlier of (i) a request by the Company or (ii)
termination on my employment. After such delivery, I shall not retain any such
records or copies thereof or any such tangible property.

Notwithstanding the foregoing, in the event that I am required (by oral
questions, interrogatories, requests for information or documents, subpoena,
civil investigative demand, or similar process) to disclose any Proprietary
Information, I shall provide to the Company with prompt notice thereof so that
the Company may seek any appropriate protective order and/or waive compliance by
me with the provisions hereof; provided, however, if in the absence of a
protective order or the receipt of a waiver hereunder, I am, in the opinion of
my counsel (such opinion to be reasonably acceptable to the Company) compelled
so to disclose Proprietary Information not otherwise disclosable hereunder to
any legislative, judicial, or regulatory body, agent, or authority, or else be
exposed to liability for contempt, fine, or penalty, or to other censure, such
Proprietary Information may be so disclosed to the extent necessary to comply
with such disclosure requirement. The parties agree that in the event that I am
given an opinion of my counsel (such opinion to be reasonably acceptable to the
Company) that (i) failing to retain a copy or sample of such Proprietary
Information would violate an applicable federal, state, local, or foreign law,
or (ii) maintaining the Proprietary Information would be needed to protect my
interest in existing or potential civil, regulatory or criminal action, I shall
be permitted to retain copies of the Proprietary Information relevant to such
matter or action, provided that I provide the Company with a written log of such
Proprietary Information and promptly return such Proprietary Information to the
Company when retention hereof is no longer necessary for such purposes.

      (c)   I agree that my obligation not to disclose or to use information,
know-how and records of the types set forth in paragraphs (a) and (b) above, and
my obligation to return records and tangible property, set forth in paragraph
(b) above, also extends to such types of information, know-how, records, and
tangible property of customers of the Company or suppliers of the Company or
other third parties who may have disclosed or entrusted the same to the Company
or to me in the course of the Company's business. Information, know-how,
records, and tangible property of customers of the Company or suppliers of the
Company or third parties, which was received prior to my employment with the
Company or is public record and information, are excluded from my obligation to
return records and tangible property to the Company.

3.    Developments.

      (a)   I will make full and prompt disclosure to the Company of all
inventions, improvements, discoveries, methods, developments, software, and
works of authorship, whether patentable or not, which are created, made,
conceived or reduced to practice by me or under my direction or jointly with
others during my employment by the Company, whether or not during normal working
hours or on the premises of the Company (all of which are collectively referred
to in this Agreement as "Developments").

      (b)   I agree to assign and do hereby assign to the Company (or any person
or entity designated by the Company) all my rights, title, and interest in and
to all Developments and all

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related patents, patent applications, copyrights, copyright applications, mask
works and applications to register mask works (both in the United States and in
foreign countries). However, this paragraph 3(b) shall not apply to Developments
which do not relate to the present or the planned business or research and
development of the Company and which are made and conceived by me not during
normal working hours, not on the Company's premises and not using the Company's
tools, devices, equipment or Proprietary Information. I understand that, to the
extent this Agreement shall be construed in accordance with the laws of any
state which precludes a requirement in an employee agreement to assign certain
classes of inventions made by an employee, this paragraph 3(b) shall be
interpreted not to apply to any invention which a court rules and/or the Company
agrees falls within such classes.

      (c)   I agree to cooperate fully with the Company, both during and after 
my employment with the Company, with respect to the procurement, maintenance and
enforcement of copyrights and patents (both in the United States and foreign
countries) relating to Developments. I shall sign all papers, including, without
limitation, copyright applications, patent applications, declarations, oaths,
formal assignment of priority rights, and powers of attorney, which the Company
may deem necessary or desirable in order to protect its rights and interests in
any Development.

      (d)   In the event the Company is unable, after reasonable effort, to 
secure my signature on any letters patent, copyright or other analogous
protection relating to Developments, whether because of my physical or mental
incapacity or for any other reason whatsoever, I hereby irrevocably designate
and appoint the Company and its duly authorized officers and agents and
attorney-in-fact, to act for and on my behalf and stead to execute and file any
such application or applications and to do all other lawfully permitted acts to
further the prosecution and issuance of letters patent, copyright or other
analogous protection thereon with the same legal force and effect as if executed
by me.

4.    Non-Competition.

      I agree that during the term of my employment with the Company and for a
period of three (3) years after the termination of such employment, irrespective
of the reason for such termination, I will not (a) directly engage in, or (b)
participate as an officer, director, partner, joint venturer, employee or agent
of, or as the holder of more than 1% of the equity interests in, or as a
consultant or independent contractor to, any corporation, partnership, or other
entity or business which engages in any business which is substantially similar
to, or functionally equivalent to, the Company's Catalytic Extraction Processing
technology. I agree to notify the Company in writing prior to accepting any
employment or consulting relationship with any entity which engages in such
activity. The Company agrees to respond in writing to such notification within 7
days of receipt indicating whether or not the Company reasonably considers such
employment or consulting relationship to be covered by the foregoing
non-competition agreement. However, nothing herein shall prohibit me from owning
more than 1% of any class of securities of any publicly traded entity.

      I further agree that, during such employment and for three years
thereafter, I will not, directly or indirectly, employ, or knowingly permit any
company or business organization directly 


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or indirectly controlled by me to employ, any person who is then employed by the
Company or in any manner seek to induce any such person to leave his or her
employment with the Company.

5.    Other Agreements.

      I hereby represent that, except as I have disclosed in writing to the
Company and attached hereto as Exhibit A, I am not bound by the terms of any
agreement with any previous employer or other party to refrain from using or
disclosing any trade secret or confidential or proprietary information in the
course of my employment with the Company or to refrain from competing, directly
or indirectly, with the business of such previous employer or any other party. I
further represent that my performance of all the terms of this Agreement and as
an employee of the Company does not and will not breach any agreement to keep in
confidence proprietary information, knowledge or data acquired by me in
confidence or trust prior to my employment with the Company to use any
confidential or proprietary information of material belonging to any previous
employer or others.

6.    United States Government Obligations.

      I acknowledge that the Company from time to time may have agreements with
the other persons or with the United States Government, or agencies thereof,
which impose obligations or restrictions on the Company regarding inventions
made during the course of work under such agreements or regarding the
confidential nature of such work. I agree to be bound by all such obligations
and restrictions which are made known to me and to take all action necessary to
discharge the obligations of the Company under such agreement.

7.    Certain Claims Upon Termination.

      (a)   I understand that if within one year prior to the termination of my
employment with the Company I have engaged in any specified action (as defined
below):

            (i)   The Company will have no obligation to provide severance in 
            the manner described below.

            (ii)  Any Option awarded to me under any Stock Option Award 
            Agreement or Restricted Stock Award Agreement (each, an "Award
            Agreement") from the Company to me shall terminate as of the date of
            such termination, and notwithstanding anything contained in the
            Award Agreement or the Plan (as defined in the Award Agreement), I
            shall have no further right to purchase shares of Common Stock of
            the Company pursuant to the Option or the Award Agreement,
            irrespective of whether such shares are Vested under the Award
            Agreement at the time of such termination; and


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            (iii) the Company shall have the right to purchase any or all shares
            of Common Stock of the Company owned by me at the time of such
            termination which were acquired pursuant to the exercise of any
            Award Agreement for a purchase price equal to the amount that I paid
            for such shares, together with interest thereon at a rate of the
            then prime rate per annum. If the Company desires to exercise such
            right, it shall notify me within sixty (60) days after the date of
            such termination and I shall tender the shares being purchased by
            the Company at the time and place designated in such notice from the
            Company upon receipt of the purchase price for such shares. If I
            fail to so tender such shares, the shares shall be deemed to be
            canceled as of the date the Company tenders payment of the purchase
            price thereof.

      (b)   For purposes of this Section 7, I shall be deemed to have engaged in
a specified action if the Company has determined that any of the following shall
have occurred:

            (i)   I shall have committed an act of theft, dishonesty, gross
            dereliction of duty, fraud, embezzlement, misappropriation, or
            breach of fiduciary duty against the Company or any other act of
            comparable misconduct against the Company;

            (ii)  I shall have been convicted by a court of competent
            jurisdiction of, or pleaded guilty or nolo contendere to, any felony
            or any crime involving moral turpitude or dishonesty; or

            (iii) I shall have breached any of my obligations under this
            Agreement.

      (c)   For the purposes of this Section 7, severance consists of continuing
to pay my weekly rate of pay then in effect, but not less than $4,807.69 per
week, for a period of up to five years or until I have found other work with
compensation equivalent to 50% of my base salary in effect at the time of the
termination, whichever comes first. Such payments will be contingent upon my
following the Company's customary "exit procedures" which include the signing of
a standard severance agreement (at hearing understood that there shall be no
expressed or implied obligation for me to seek other employment in order to
receive to such severance payments). My right to receive severance payments
hereunder shall terminate on the tenth anniversary of the date hereof.

      (d)   I understand that if I am involuntarily terminated for any reason
and I have not engaged in a specified action or if I die or become permanently
disabled, the restrictions on the grant of restricted stock awarded to me with
my offer of employment will be lifted.

      (e)   I understand that if I am involuntarily terminated for any reason
(including, but without limitation, as a result of downsizing, reorganization or
a change of control of the Company), and I have not engaged in a specified
action, I will receive severance according to Section 7(c). The parties agree
that a reduction in my salary below $4,807.69 per week shall constitute
involuntary termination.

      (f)   I further understand that if I resign voluntarily for any reason, I
will not be entitled to receive severance.


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8.    Miscellaneous.

      (a)   The invalidity or unenforceability of any provision of this 
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement.

      (b)   This Agreement supersedes all prior agreements, written or oral,
between me and the Company, relating to the subject matter of this Agreement.
This Agreement may not be modified, changed or discharged in whole or in part,
except by an agreement in writing signed by me and the Company. I agree that any
change or changes in my duties, salary or compensation after the signing of this
Agreement shall not affect the validity or scope of this Agreement.

      (c)   This Agreement will be binding upon my heirs, executors and
administrators and will inure to the benefit of the Company and its successors
and assigns.

      (d)   No delay or omission by the Company in exercising any right under 
this Agreement will operate as a waiver of that or any other right. A waiver or
consent given by the Company on any one occasion is effective only in that
instance and will not be construed as a bar to or waiver of any right on any
other occasion.

      (e) By acceptance hereof the Company specifically confirms to me that I
shall be entitled to be indemnified by the Company in my capacity as an officer
or director of the Company to the same extent that officers and directors are
generally indemnified by the Company.

      (f)   In view of the substantial harm which will result from my breach of
any of the provisions contained in Sections 2, 3, or 4 above, I agree that such
provisions shall be enforced to the fullest extent permitted by law.
Accordingly, I agree that if, in any judicial proceeding, a court shall
determine that such provisions are unenforceable because they cover too
extensive a geographic area or survive for too long a period of time, or for any
other reason, such provisions shall be deemed to cover such maximum geographic
area and maximum period of time and shall otherwise be deemed to be limited in
such a manner as will permit enforceability by such court.

      (g)   I agree that my breach of any of the provisions of Sections 2, 3, or
4 above will cause irreparable damage to the Company and that the recovery by
the Company of money damages will not constitute an adequate remedy for such
breach. Accordingly, I agree that the provisions of Sections 2, 3, or 4 above
may be specifically enforced against me in addition to any other rights or
remedies available to the Company on account of such breach, and I hereby
recognize that if there is material violation of the provisions of Sections 2,
3, or 4 above, the Company shall be entitled to an injunction or similar
equitable relief to be issued by court of competent standing.

      (h)   This Agreement is governed by and will be construed as a sealed
instrument under and in accordance with the laws of the Commonwealth of
Massachusetts.


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      I HAVE READ ALL OF THE PROVISIONS OF THIS AGREEMENT AND I UNDERSTAND, AND
AGREE TO, EACH OF SUCH PROVISIONS.


                                        By: /s/ Garnet Earl McConchie
                                           -------------------------------
                                           Earl McConchie

Accepted as of the
date above written:
                           Dated as of March 29, 1996


MOLTEN METAL TECHNOLOGY, INC.


By: /s/ Katharyn Santoro
   -------------------------------

Date:  April 1, 1996




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