Confidentiality Agreement

And Confidentiality Agreement

by American Power Group
October 9th, 1998


                    COVENANT NOT TO COMPETE/NON-SOLICITATION
                          AND CONFIDENTIALITY AGREEMENT

      THIS COVENANT NOT TO COMPETE/NON-SOLICITATION AND CONFIDENTIALITY
AGREEMENT (this "Agreement") is made and entered into this 4th day of September,
1998 by and among UNITED WASTE SERVICES, INC. ("UWS"), a Georgia corporation,
Republic Services, Inc. ("Republic"), a Delaware corporation (hereinafter UWS
and Republic are referred to as ("United") and GREENMAN TECHNOLOGIES, INC., a
Delaware corporation ("GreenMan").

                                    RECITALS:

      WHEREAS, on the date hereof, pursuant to that certain Asset Purchase
Agreement, dated as of September 4, 1998 (the "Asset Purchase Agreement"),
between GreenMan and United, GreenMan acquired from United certain assets used
in the operation of United's scrap tire and collection business.

      WHEREAS, pursuant to Section 3.2.12 of the Asset Purchase Agreement,
United agreed, among other things, to enter into the Agreement and to refrain
from certain activities competitive with those of GreenMan in the business of
tire collection and shredding.

      WHEREAS, in order that GreenMan realizes the full value and goodwill
inherent in the assets acquired pursuant to the Asset Purchase Agreement, the
parties hereto mutually desire that United execute and deliver this Agreement in
favor of GreenMan.

                                   AGREEMENT:

      FOR AND IN CONSIDERATION of the Agreements contained in this Agreement and
for other good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, the parties hereto agree as follows:

                                    ARTICLE I
                              Restrictive Covenants

      1.1 United, on behalf of itself and its Affiliates (as hereinafter
defined), subsidiaries, to the extent applicable, successors and assigns agrees,
for a period of five (5) years commencing on the date hereof and terminating on
the fifth anniversary of the date the parties entered into this Agreement, not
to:

            1.1.1 Directly or indirectly engage in (as an owner, partner,
      employee, agent, consultant or otherwise) the tire collection and
      shredding business in the States of 



      Georgia, Florida, Alabama, South Carolina, North Carolina, Tennessee,
      Kentucky or Virginia (collectively, the "Territory") or acquire or retain
      any financial interest having a fair value in excess of the lesser of
      $500,000 in, or 5% of the equity of, any business that is so engaged in
      the Territory; or

            1.1.2 (i) Induce any customer of GreenMan or its Affiliates to
      patronize any business that is in direct or indirect competition with the
      tire collection and shredding business of GreenMan or its Affiliates; (ii)
      canvass, solicit or accept from any customer of GreenMan or its Affiliates
      any business that competes with the tire shredding and collection business
      of GreenMan or its Affiliates; or (iii) request or advise any individual
      or company that is a customer of GreenMan or its Affiliates to withdraw,
      curtail or cancel any such customer's business with GreenMan or its
      Affiliates.

            1.1.3 Solicit or endeavor to entice away any dealer, distributor,
      sales representative, officer or employee of GreenMan or its Affiliates,
      including without limitation those former employees of RSI or United hired
      by GreenMan or its Affiliates following the Closing under the Asset
      Purchase Agreement.

Notwithstanding anything to the contrary herein, GreenMan acknowledges that the
ownership by United, or any of its Affiliates, of less than five percent (5%) of
the shares of stock of any corporation having a class of equity securities
actively traded on a National Securities Exchange or over the counter market
shall not be a violation of this Agreement. For the purposes of this Agreement,
the term "Affiliate" shall mean any individual, corporation, partnership, joint
venture, trust or unincorporated organization or association, joint stock
company or other similar organization or legal entity, that controls, or is
controlled by, or is under common control with GreenMan, RSI or United, as the
case may be, whether such control be direct or indirect. As used in the
foregoing sentence, the term "control" means the possession, directly or
indirectly, of the power to direct or cause the direction of the management and
policies of such individual, corporation, partnership, joint venture, trust or
unincorporated organization or association, joint stock company or other similar
organization or legal entity, whether through the ownership of voting
securities, by contract or otherwise.

      1.2 If any provision of paragraph 1.1 of this Article I is adjudged by a
court to be invalid or unenforceable, the same will in no way affect any other
provision of the said paragraph 1.1 or any other part of this Agreement, the
application of such provision in any other circumstances or the validity or
enforceability of this Agreement. If any such provision, or any part thereof, is
held to be unenforceable because of the duration of such provision or the
geographic area covered thereby or the nature of the business activity covered
thereby, the parties agree that the court making such determination shall reduce
the duration, geographic area, and/or business coverage of such provision,
and/or to delete specific words or phrases, and in its reduced form such
provision will then be enforceable and will be enforced. Upon a breach of any
provision of paragraph 1.1, GreenMan shall be entitled to injunctive relief and
specific 


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performance, because the remedy at law would be inadequate and insufficient. In
addition, GreenMan shall be entitled to all other damages as provided by law.

                                   ARTICLE II
                            Confidentiality Agreement

      United, on behalf of itself and its Affiliates agrees and warrants that,
for a period of five (5) years from the date hereof, it will not, directly or
indirectly, at any time divulge, furnish, or make accessible to anyone, or
appropriate to its own use, or to the use of any third party, any knowledge or
information with respect to secret, confidential or proprietary methods,
processes, formulae, designs, equipment, plans, projects, material, information,
business, operations, techniques or customer lists of United; provided, however,
that the foregoing restriction shall not apply to information that (i) is in the
public domain or becomes part of the public domain through no fault of United,
(ii) is used by United in businesses other than Untied's tire collection and
shredding business, or (iii) United is required to disclose by order of a court
of competent jurisdiction in any legal proceeding, provided that United shall
notify GreenMan before so disclosing such information.

                                   ARTICLE III
                                  Miscellaneous

      3.1 Amendment and Modification. The parties hereto may amend, modify and
supplement this Agreement in such manner as may be agreed upon by them in
writing.

      3.2 Entire Agreement. This Agreement, including the exhibits and
schedules, contains the entire agreement of the parties hereto with respect to
the purchase of the Purchased Assets and the other transactions contemplated
hereby, and supersedes all prior understandings and agreements (oral and
written) of the parties with respect to the subject matter hereof. The parties
expressly represent and warrant that in entering into this Agreement they are
not relying on any prior representations made by any other party concerning the
terms, conditions or effects of this Agreement which terms, conditions and
effects are not expressly set forth herein. Any reference herein to this
Agreement shall be deemed to include the schedules and exhibits, if any.

      3.3 Interpretation. The descriptive headings in this Agreement are
inserted for convenience only and shall not affect in any way the meaning or
interpretation of this Agreement. When a reference is made in this Agreement to
an article, section, paragraph, clause, schedule or exhibit, such reference
shall be to an article, section, paragraph, clause, schedule or exhibit to this
Agreement unless otherwise indicated. Whenever the words "include", "includes"
or "including" are used in this Agreement, they shall be deemed to be followed
by the words "without limitation". Time shall be of the essence in this
Agreement.


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      3.4 Execution in Counterpart. This Agreement may be executed in any number
of counterpart, each of which shall be deemed an original, but all of which
taken together shall constitute one and the same Agreement.

      3.5 Notices. Any notice, consent, approval, request, other communications
or information to be given or made hereunder to any of the parties by any other
party shall be in writing and (a) delivered personally, (b) sent by express
delivery service or certified mail, postage prepaid, or (c) sent by facsimile as
follows:

      If to RSI or United, addressed to:

                        Republic Services, Inc.
                        110 S.E. 6th Street
                        Suite 2800
                        Ft. Lauderdale, Florida 33301
                        Attn: General Counsel
                        Fax: (954) 769-6527

      If to the GreenMan, addressed to:

                        GreenMan Technologies, Inc.
                        7 Kimball Lane
                        Building A.
                        Lynnfield, Massachusetts 01940
                        Attn: President
                        Fax: (781) 224-0114

      Any party may change the address to which notices hereunder are to be sent
to it by giving written notice of such change of address in the manner herein
provided for giving notice. Any notice delivered personally shall be deemed to
have been given on the date it is so delivered, and any notice delivered by
express delivery service or certified mail shall be deemed to have been given on
the date it is received, and any notice given by facsimile transmission shall be
deemed to have been give on the date sent (so long as sender receives
confirmation of transmission and a hard copy of such notice is sent by U.S.
mail).

      3.6 Governing Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware applicable to contracts made
and to be performed therein.

      3.7 Severability. If any term or other provision of this Agreement is
invalid, illegal or incapable of being enforced by any rule of law or public
policy, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the 


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      3.7 Severability. If any term or other provision of this Agreement is
invalid, illegal or incapable of being enforced by any rule of law or public
policy, all other conditions and provisions of this Agreement shall nevertheless
remain in full force and effect so long as the economic or legal substance of
the transactions contemplated hereby is not affected in any manner adverse to
any party. Upon such determination that any term or other provision is invalid,
illegal or incapable of being enforced, the parties hereto shall negotiate in
good faith to modify this Agreement so as to effect the original intent of the
parties as closely as possible in an acceptable manner to the end that the
transaction contemplated hereby are fulfilled to the greatest extent possible.

      3.8 Assignment. Neither this Agreement nor any of the rights, interests or
obligations hereunder shall be assigned by any of the parties hereto without the
prior consent of the other party.

      3.9 Binding Effect; No Third Party Beneficiaries. This Agreement shall
inure to the benefit of, be binding upon and be enforceable by and against the
Seller and the Purchaser and their respective successors and permitted assigns,
and nothing herein expressed or implied shall be construed to give any other
person or entity any legal or equitable rights hereunder.

      IN WITNESS WHEREOF, the undersigned have caused this Agreement to be duly
executed as of the day and year first above written.

UNITED WASTE SERVICES, INC.                REPUBLIC SERVICES, INC.


By:    /s/ David A. Barclay                By:    /s/ David A. Barclay
       -------------------------                  -------------------------
Name:  David A. Barclay                    Name:  David A. Barclay
       -------------------------                  -------------------------
Title: Assistant Secretary                 Title: Senior Vice President
       -------------------------                  -------------------------


                                           GREENMAN TECHNOLOGIES, INC.


                                           By:    /s/ Charles E. Coppa
                                                  -------------------------
                                           Name:  Charles E. Coppa
                                                  -------------------------
                                           Title: Acting CFO
                                                  -------------------------


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