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                                                                   EXHIBIT 10.13



                              MANAGEMENT AGREEMENT

THIS AGREEMENT, entered into the 31st day of March, 2000 between Liberty Waste,
Inc., a Florida corporation ("Liberty") and EarthCare Company, a Delaware
corporation ("EarthCare").

         In consideration of the following mutual covenants, the parties agree
as follows:

         1.       RECITATIONS. Liberty and EarthCare desire to enter into an
                  agreement for EarthCare to furnish various management services
                  in exchange for a management fee. EarthCare has hired
                  executive personnel and invested in data processing assets in
                  anticipation of entering into this Agreement. EarthCare has
                  familiarized itself with the business of Liberty and has
                  consulted with various professionals and investment bankers
                  regarding the business of Liberty.

         2.       MANAGEMENT SERVICES. During the term of this Agreement,
                  EarthCare shall provide the following services for Liberty:

                  (a)      Accounting services;

                  (b)      Investment banking advisory services;

                  (c)      Information and data processing services;

                  (d)      Bid and bond advice;

                  (e)      Municipal contract assistance; and

                  (f)      Commercial banking services.

         3.       MANAGEMENT FEES. In exchange for the management services to be
                  furnished hereunder, Liberty shall pay EarthCare management
                  fees as follows:

                  (a)      $500,000 upon the execution of this Agreement; and

                  (b)      $75,000 per month, commencing April 15, 2000, for the
                           term of this Agreement.


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         4.       TERM. This Agreement shall be for a term commencing March 31,
                  2000 and ending on March 31, 2001, and shall be renewed
                  automatically for additional one - year terms unless
                  terminated by either party by giving not less than 60 days
                  written notice prior to the end of a term to the other party.

         5.       REPRESENTATIONS AND WARRANTIES OF LIBERTY.

                  (a)      Liberty is a corporation duly organized and legally
                           existing in good standing under the laws of the State
                           of Florida, and has all the requisite corporate power
                           and authority to carry on its business as now
                           conducted.

                  (b)      The execution, delivery and performance of this
                           Agreement by Liberty has been duly approved by its
                           Board of Directors, and no further corporate action
                           is necessary on the part of Liberty to consummate the
                           transactions contemplated by this Agreement, assuming
                           due execution of this Agreement by the Parties.

                  (c)      Liberty maintains in effect insurance covering its
                           assets and businesses and any liabilities relating
                           thereto in an amount believed adequate by Liberty,
                           and such insurance coverage shall be maintained by
                           Liberty.

                  (d)      Liberty possesses all licenses and other required
                           governmental or official approvals, permits or
                           authorizations, if any, the failure to possess which
                           would have a material adverse effect on the business,
                           financial condition or results of operations of
                           Liberty including, without limitation, all common
                           carrier rights, certificates of public need, waste
                           material transportation permits, trademarks and trade
                           names necessary to carry on its business as now being
                           conducted, without known conflict with valid
                           licenses, permits, trademarks and trade names of
                           others. All such licenses and permits are in full
                           force and effect, and no violations are or have been
                           recorded in respect to any thereof, and no proceeding
                           is pending, or to the knowledge of Liberty
                           threatened, to revoke, suspend or otherwise limit
                           such licenses or permits. All licenses and permits
                           will survive the closing of the transactions
                           contemplated by this Agreement.

                  (e)      No agent, broker, finder, representative or other
                           person or entity acting pursuant to authority of
                           Liberty will be entitled to any commission or


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                           finder's fee in connection with the origination,
                           negotiation, execution or performance of the
                           transactions contemplated under this Agreement.

                  (f)      This Agreement and all other agreements of Liberty
                           contemplated hereunder constitute valid and binding
                           obligations of Liberty, enforceable in accordance
                           with their respective terms. Neither the execution
                           and delivery of this Agreement (or any agreement
                           contemplated hereunder) nor the consummation of the
                           transactions contemplated hereby will: (i) conflict
                           with or violate any provision of the Articles of
                           Incorporation or By-Laws of Liberty; (ii) conflict
                           with or violate any decree, writ, injunction or order
                           of any court or administrative or other governmental
                           body which is applicable to, binding upon or
                           enforceable against Liberty; or (iii) result in any
                           breach of or default (or give rise to any right of
                           termination, cancellation or acceleration) under any
                           mortgage, contract, agreement, indenture, will, trust
                           or other instrument which is either binding upon or
                           enforceable against Liberty or its assets.

                  (g)      Liberty has the full power, right and authority to
                           enter into and perform this Agreement without the
                           consent of any person, entity, or governmental
                           agency, and the consummation of the transactions
                           contemplated by this Agreement will not result in the
                           breach or termination of any provision of or
                           constitute a default under any lease, indenture,
                           mortgage, deed of trust or other agreement or
                           instrument or any order, decree, statute or
                           restriction to which Liberty is a party or by which
                           Liberty is bound or to which the outstanding shares
                           of stock of Liberty or any of the properties of
                           Liberty is subject.

                  (h)      No representation, statement or information made or
                           furnished by Liberty to EarthCare, including those
                           contained in this Agreement and the other information
                           and statements referred to herein, contains or shall
                           contain any untrue statement of any material fact.

         6. REPRESENTATIONS AND WARRANTIES OF EARTHCARE.

                  (a)      EarthCare is a corporation duly organized, validly
                           existing and in good standing under the laws of the
                           State of Delaware and has all the requisite corporate
                           power and authority to carry on its business as now
                           conducted and to consummate the transactions
                           contemplated by this


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                           Agreement.

                  (b)      The execution, delivery and performance of this
                           Agreement by EarthCare has been duly approved by its
                           Board of Directors, and no further corporate action
                           is necessary on the part of EarthCare to consummate
                           the transactions contemplated by this Agreement,
                           assuming due execution of this Agreement by the
                           Parties.

                  (c)      No agent, broker, finder, representative or other
                           person or entity acting pursuant to the authority of
                           EarthCare will be entitled to any commission or
                           finder's fee in connection with the origination,
                           negotiation, execution or performance of the
                           transactions contemplated under this Agreement.

                  (d)      This Agreement and all other agreements of EarthCare
                           contemplated hereunder constitute valid and binding
                           obligations of EarthCare, enforceable in accordance
                           with their respective terms. Neither the execution
                           and delivery of this Agreement (or any agreement
                           contemplated hereunder) nor the consummation of the
                           transactions contemplated hereby will: (i) conflict
                           with or violate any provision of the Articles of
                           Incorporation or By-Laws of EarthCare; (ii) conflict
                           with or violate any decree, writ, injunction or order
                           of any court or administrative or other governmental
                           body which is applicable to, binding upon or
                           enforceable against EarthCare; or (iii) result in any
                           breach of or default (or give rise to any right of
                           termination, cancellation or acceleration) under any
                           mortgage, contract, agreement, indenture, will, trust
                           or other instrument which is either binding upon or
                           enforceable against EarthCare or its assets.

                  (e)      EarthCare has the full power, right and authority to
                           enter into and perform this Agreement without the
                           consent of any person, entity, or governmental
                           agency, and the consummation of the transactions
                           contemplated by this Agreement will not result in the
                           breach or termination of any provision of or
                           constitute a default under any lease, indenture,
                           mortgage, deed of trust or other agreement or
                           instrument or any order, decree, statute or
                           restriction to which EarthCare is a party or by which
                           EarthCare is bound or to which the outstanding shares
                           of stock of EarthCare or any of the properties of
                           EarthCare is subject.


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                  (f)      No representation, statement or information made or
                           furnished by EarthCare to Liberty in this Agreement,
                           or in connection with the transactions contemplated
                           hereby contains, or shall contain any untrue
                           statement of any material fact or omits or shall omit
                           any material fact necessary to make the information
                           contained herein true.

         7.       MATERIAL CONTRACTS, ETC. In anticipation of the acquisition by
                  EarthCare of a significant minority interest in Liberty,
                  Liberty shall not, without the written consent of EarthCare,
                  issue or enter into any subscriptions, options, agreements or
                  other commitments in respect of the issuance, transfer, sale
                  or encumbrance of any shares of Liberty common stock, or enter
                  into any material transactions outside the ordinary course of
                  business.

         8.       INDEMNIFICATION BY LIBERTY.

                  (a)      Liberty shall indemnify and hold EarthCare harmless
                           from and against any and all damages, loss, cost,
                           deficiency, assessment, liability or other expense
                           (including reasonable attorney's fees, costs of court
                           and costs of litigation, if any) suffered, incurred
                           or paid by EarthCare as a result of:

                           (i)      The untruth, inaccuracy, breach or violation
                                    of any representation, warranty covenant or
                                    other obligation of Liberty set forth in or
                                    made in connection with this Agreement.

                           (ii)     The assertion against EarthCare of any
                                    liabilities or obligations of Liberty or any
                                    claim relating to the operations of
                                    Liberty's business; or

                           (iii)    The enforcement of EarthCare's right to
                                    indemnification under this Agreement.

                  (b)      EarthCare shall give written notice to Liberty of any
                           claim, action, suit or proceeding relating to the
                           indemnity herein provided by Liberty not later than
                           ten (10) days after EarthCare has received notice
                           thereof. Liberty shall have the right, at its option,
                           to compromise or defend, at its own expense and by
                           its own counsel (which counsel shall be reasonably
                           satisfactory to EarthCare), any such action, suit or
                           proceeding. EarthCare and Liberty agree to cooperate
                           in any such


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                           defense or settlement and to give each other full
                           access to all information relevant thereto.

                  (c)      Except as herein expressly provided, the remedies
                           provided in Paragraph 8 hereof shall be cumulative
                           and shall not preclude assertion by EarthCare or the
                           seeking of any other remedies available against
                           Liberty at law or in equity.

                  (d)      The indemnification shall not extend to damages or
                           costs caused by the willful or wrongful acts of
                           EarthCare, including, without limitation, violations
                           of federal, state or local laws.

         9.       INDEMNIFICATION BY EARTHCARE

                  (a)      EarthCare shall indemnify and hold Liberty harmless
                           from and against any and all damages, loss, cost,
                           deficiency, assessment, liability or other expense
                           (including reasonable attorney's fees, costs of court
                           and costs of litigation, if any) suffered, incurred
                           or paid by Liberty as a result of:

                           (i)      The untruth, inaccuracy, breach or violation
                                    of any representation, warranty, covenant or
                                    other obligation of EarthCare set forth in
                                    or made in connection with this Agreement.

                           (ii)     The assertion against Liberty of any
                                    liabilities or obligations of EarthCare or
                                    any claim relating to the operations of
                                    EarthCare's business; or

                           (iii)    The enforcement of Liberty's right to
                                    indemnification under this Agreement.

                  (b)      Liberty shall give written notice to EarthCare of any
                           claim, action, suit or proceeding relating to the
                           indemnity herein provided by EarthCare not later than
                           ten (10) days after Liberty has received notice
                           thereof. EarthCare shall have the right, at its
                           option, to compromise or defend, at its own expense
                           and by its own counsel (which counsel shall be
                           reasonably satisfactory to Liberty), any such action,
                           suit or proceeding. EarthCare and Liberty agree to
                           cooperate in any such defense or


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                           settlement and to give each other full access to all
                           information relevant thereto.

                  (c)      Except as herein expressly provided, the remedies
                           provided in Paragraph 9 hereof shall be cumulative
                           and shall not preclude assertion by Liberty or the
                           seeking of any other remedies available against
                           EarthCare at law or in equity.

                  (d)      The indemnification shall not extend to damages or
                           costs caused by the willful or wrongful acts of
                           Liberty, including, without limitation, violations of
                           federal, state or local laws.


         10.      WAIVER OR EXTENSION OF CONDITIONS. Liberty or EarthCare may
                  extend the time for or waive the performance of any of the
                  obligations of the other party, waive any inaccuracies in the
                  representations or warranties by the other party, or waive
                  compliance by the other party with any of the covenants or
                  conditions contained in this Agreement. Any such extension or
                  waiver shall be in writing and signed by the Liberty and
                  EarthCare. Any such extension or waiver shall not act as a
                  waiver or an extension of any other provisions of this
                  Agreement.

         11.      NOTICES. Any notice, request or other document shall be in
                  writing and sent by registered or certified mail, return
                  receipt requested, postage prepaid and addressed to the party
                  to be notified at the following addresses, or such other
                  address as such party may hereafter designate by written
                  notice to all parties, which notice shall be effective as of
                  the date of posting:

                           (a)      If to EarthCare:
                                    EarthCare Company
                                    14901 Quorum Drive
                                    Suite 200
                                    Dallas, TX 75240

                                    Copy to:

                                    Robert C. Gist, Esq.
                                    12809 Plum Hollow Drive
                                    Oklahoma City, OK 73142-5148


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                           (b)      If to Liberty




                                    Copy to:




         12.      GOVERNING LAW. This Agreement shall be governed by the laws of
                  the State of Texas.

         13.      SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon
                  and inure to the benefit of the parties hereto and their
                  respective heirs, representatives, successors and assigns.

         14.      HEADINGS. The subject headings of the Sections of this
                  Agreement are included for purposes of convenience only and
                  shall not affect the constructions or interpretation of any of
                  its provisions.

         15.      COUNTERPARTS. This Agreement may be executed simultaneously in
                  two or more counterparts, each of which shall be deemed an
                  original and all of which together shall constitute but one
                  and the same instrument.

         16.      ARBITRATION.  Any controversy or claim arising out of, in
                  connection with, or relating to this Agreement or a breach
                  thereof shall be settled by binding arbitration in
                  Dallas, Texas. The arbitration panel shall be comprised of
                  three arbitrators. Each party shall appoint one arbitrator for
                  the panel and the two so appointed shall appoint a third. The
                  panel shall resolve the dispute within sixty (60) days of the
                  appointment of the panel and shall notify the parties of its
                  findings in writing. Each party agrees to bear its own costs
                  of arbitrators and to split equally the cost of the third
                  arbitrator.

         17.      ENTIRE AGREEMENT; MODIFICATION. This Agreement constitutes the
                  entire agreement and understanding between the parties, and
                  supersede any prior agreements and understandings relating to
                  the subject matter hereof. This Agreement may be modified or
                  amended only by a written instrument executed by all parties
                  hereto.


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         IN WITNESS WHEREOF the parties have executed this Agreement on the date
first above written.



Liberty Waste, Inc.



By:
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EarthCare Company



By:
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