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                                                                   EXHIBIT 10.22

                              EMPLOYMENT AGREEMENT


      THIS EMPLOYMENT AGREEMENT, made and entered into as of the 19th day of
February, 1999 (the "EFFECTIVE DATE"), by and between Synagro Technologies,
Inc., a Delaware corporation (hereafter "COMPANY") and Alvin L. Thomas II
(hereafter "EXECUTIVE"), an individual;

                              W I T N E S S E T H:

      WHEREAS, Company wishes to secure the services of the Executive subject
to the terms and conditions hereafter set forth; and

      WHEREAS, the Executive is willing to enter into this Agreement upon the
terms and conditions hereafter set forth,

      NOW, THEREFORE, in consideration of the mutual promises and agreements set
forth herein, the parties hereto agree as follows:

      1. EMPLOYMENT. During the Employment Period (as defined in Section 4
hereof), the Company shall employ Executive, and Executive shall serve, as
Executive Vice President and General Counsel of the Company. Executive's
principal place of employment shall be at the Company's principal corporate
offices in Houston, Texas during the Employment Period.

      2. COMPENSATION. The Company shall pay or cause to be paid to Executive
during the Employment Period an annual base salary for his services under this
Agreement of not less than $120,000, payable in equal monthly or semi-monthly
installments in accordance with the Company's normal payroll procedures.
Executive's base salary shall be subject to annual review and may be increased,
depending upon the performance of the Company and Executive, upon the
recommendation of the Chairman or the Board of Directors of the Company
(hereafter "BOARD OF DIRECTORS"). Executive shall be entitled to participate in
the bonus "pool" or other structure established for the Company's top level of
management. Nothing contained herein shall preclude the payment of a bonus,
supplemental or incentive compensation to Executive provided that the Board of
Directors authorizes any such compensation payment. As additional compensation
to Executive for the services previously rendered by him, the services to be
rendered by him pursuant to, and Executive's other duties and obligations
arising under this Agreement, including, without limitation, his obligations
under Sections 12 and 14 hereof, the Company has granted to Executive options to
purchase 200,000 shares of common stock of the Company, par value $.002 per
share, between the Company and Executive.
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      3. DUTIES AND RESPONSIBILITIES OF EXECUTIVE. During the Employment Period,
Executive shall devote his services full time to the business of the Company and
perform the duties and responsibilities assigned to him by Ross M. Patten or the
Board of Directors to the best of his ability and with reasonable diligence. In
determining Executive's duties and responsibilities, Ross M. Patten and the
Board of Directors shall act in good faith and shall not assign duties and
responsibilities to Executive that are not appropriate or customary with respect
to the position of Executive hereunder. This Section 3 shall not be construed as
preventing Executive from engaging in reasonable volunteer services for
charitable, educational or civic organizations, or from investing his assets in
such form or manner as will not require a material amount of his services in the
operations of the companies or businesses in which such investments are made.

      4. TERM OF EMPLOYMENT. Executive's term of employment with the Company
under this Agreement shall be for 24 consecutive months beginning on the
Effective Date, unless Notice of Termination pursuant to Section 7 is given by
either the Company or Executive to the other party. The Company and Executive
shall each have the right to give Notice of Termination at will, with or without
cause, at any time, subject to the terms of this Agreement regarding rights and
duties of the parties upon termination of employment. This 24-month employment
period hereunder shall be referred to herein as the "TERM OF EMPLOYMENT." The
period from the Effective Date through the date of Executive's termination of
employment for whatever reason shall be referred to herein as the "EMPLOYMENT
PERIOD."

      5. BENEFITS. Subject to the terms and conditions of this Agreement, during
the Employment Period, Executive shall be entitled to the following:

            (a) REIMBURSEMENT OF EXPENSES. The Company shall pay or reimburse
      Executive for all reasonable travel, entertainment and other reasonable
      expenses paid or incurred by Executive in performing his business
      obligations hereunder. The Company shall also provide Executive with
      suitable office space and secretarial help. Executive shall provide
      substantiating documentation for expense reimbursement requests as
      reasonably required by the Company for its tax and other business records.

            (b) EXPENSE ALLOWANCES. Executive shall be entitled to: (i) a car
      allowance of $500 per month, and (ii) family medical and dental insurance
      coverage paid for 100% by Company and which allows Executive to choose
      among all options for medical and dental insurance provided to other
      Company employees in the same area.

            (c) OTHER BENEFITS. Executive shall be entitled to participate in
      any pension, profit-sharing, stock option, deferred compensation, or
      similar plan or program of the Company established by the Company, to the
      extent that he is eligible under the provisions thereof. Executive shall
      also be entitled to participate in any group insurance,

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      hospitalization, medical, health and accident, disability or similar plan
      or program established by the Company, to the extent that he is eligible
      under the provisions thereof.

            (d) PAID VACATION. Executive shall initially be entitled to three
      (3) weeks of paid vacation during each 12-month period of employment with
      the Company (which shall accrue monthly on a pro rata basis). Executive
      shall thereafter be entitled to the number of days of paid vacation each
      year that is accorded under the Company's vacation policy as in effect
      from time to time or three (3) weeks, whichever is greater. Unused
      vacation days up to a maximum of two (2) weeks in one year shall be
      carried forward for a period not to exceed 12 months in accordance with
      Company's vacation policy as in effect from time to time.

      6. RIGHTS AND PAYMENTS UPON TERMINATION. The Executive's right to
compensation and benefits for periods after the date on which his employment
with the Company terminates for whatever reason (the "TERMINATION DATE") shall
be determined in accordance with this Section 6,

            (a) MINIMUM PAYMENTS. Executive shall be entitled to the following
      payments, in addition to any payments or benefits to which the Executive
      is entitled under the terms of any employee benefit plan or the following
      provisions of this Section 6:

                  (1) his unpaid salary for the full month in which his
            Termination Date occurred; provided, however, if Executive is
            terminated for Cause pursuant to Section 6(b) below, he shall only
            be entitled to receive his accrued but unpaid salary through his
            Termination Date; and

                  (2) his accrued but unpaid vacation pay for the period ending
            on his Termination Date in accordance with the Company's vacation
            pay policy as in effect at such time.

            (b) SEVERANCE PAYMENT. Notwithstanding any other provision of this
      Agreement to the contrary, in the event that: (i) Executive's employment
      hereunder is terminated by the Company at any time for any reason except
      (A) for Cause (as defined below) or (B) Executive's death or Disability
      (as defined below) or (ii) Executive terminates his own employment
      hereunder at any time for Good Reason (as defined below), then, in either
      such event, Executive shall be entitled to receive, and the Company shall
      be obligated to pay, a lump sum cash payment equal to one hundred percent
      (100%) the present value of Executive's annual salary pursuant to Section
      2 or the annual salary then being paid to him, whichever is greater. For
      purposes of the immediately preceding sentence, the "present value" of
      such annual salary shall be determined in accordance with the regulations
      under Section 280G of the Code (as defined below). Also, except as
      otherwise specifically provided in this Section 6(b), such severance
      payment shall be in addition to, and shall not reduce or offset, any other
      payments that are due to Executive from the Company or any

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      other source or under any other agreements, except any severance pay plan
      or program maintained by the Company that covers employees generally. The
      provisions of this Section 6(b) shall supersede any conflicting provisions
      of this Agreement but shall not be construed to curtail, offset or limit
      Executive's rights to any other payments, whether contingent upon a Change
      in Control (as defined below) or otherwise, under the Agreement or any
      other agreement, contract, plan or other source of payment except as
      specifically provided herein. In addition, in the event of a Change in
      Control, Executive shall be entitled to receive the bonus payment
      described in Section 9 hereof, if applicable.

            Notwithstanding any provision of this Section 6(b) to the contrary,
      the Executive must first execute an appropriate release and waiver
      agreement whereby Executive agrees to release and waive, in return for the
      severance payment described in this Section 6(b), any claims that he may
      have against the Company for (1) unlawful discrimination (including,
      without limitation, age discrimination) and (2) severance pay under any
      other severance pay plan or program maintained by the Company that covers
      Executive; provided, however, such agreement shall not release or waive
      any claims that may be brought by Executive for payments that may be due
      under this Agreement, without Executive's express written consent. Any
      severance payment required under this Section 6(b) shall be paid to
      Executive within twenty (20) days after Executive executes such release
      and waiver agreement, unless the parties agree in writing before then to
      another payment date or method of payment, e.g., installment payments.
      Executive shall not be required to mitigate any damages under this Section
      6(b) or any other provision of this Agreement.

            A "CHANGE IN CONTROL" of the Company shall be deemed to have
      occurred if any of the following shall have taken place: (1) a change in
      control is reported by the Company in response to either Item 6(e) of
      Schedule 14A of Regulation 14A promulgated under the Securities Exchange
      Act of 1934 (the "EXCHANGE ACT") or Item 1 of Form 8-K promulgated under
      the Exchange Act, or any successor provisions thereto; (2) any "person"
      (as such term is used in Sections 13(d) and 14(d)(2) of the Exchange Act)
      is or becomes the "beneficial owner" (as defined in Rule 13d-3 under the
      Exchange Act), or any successor provisions thereto, directly or
      indirectly, of securities of the Company representing twenty-five (25%) or
      more of the combined voting power of the Company's then-outstanding
      securities; (3) the approval by the stockholders of the Company of a
      reorganization, merger, or consolidation, in each case with respect to
      which persons who were stockholders of the Company immediately prior to
      such reorganization, merger, or consolidation do not, immediately
      thereafter, own or control more than fifty percent (50%) of the combined
      voting power entitled to vote generally in the election of directors of
      the reorganized, merged or consolidated Company's then outstanding
      securities, or a liquidation or dissolution of the Company or of the sale
      of all or substantially all of the Company's assets; (4) in the event any
      person shall be elected by the stockholders of the Company to the Board of
      Directors who shall have not been nominated for election by a majority of
      the Board of Directors or

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      any duly appointed committee thereof; or (5) following the election or
      removal of directors, a majority of the Board of Directors consists of
      individuals who were not members of the Board of Directors two (2) years
      before such election or removal, unless the election of each director who
      is not a director at the beginning of such two-year period has been
      approved in advance by directors representing at least a majority of the
      directors then in office who were directors at the beginning of the
      two-year period.

            "DISABILITY" means a "permanent and total disability" as defined in
      Section 22(e)(3) of the Code and the Treasury regulations thereunder.
      Evidence of such Disability shall be certified by a physician acceptable
      to both the Company and Executive. In the event that the parties are not
      able to agree on the choice of a physician, each shall select a physician
      who, in turn, shall select a third physician to render such certification.
      All costs relating to the determination of whether Executive has incurred
      a Disability shall be paid by the Company.

            "CODE" means the Internal Revenue Code of 1986, as amended.
      References in this Agreement to any Section of the Code shall include any
      "Successor Provisions" as defined in Section 9(e).

            "CAUSE" means a termination of employment directly resulting from:
      (1) the Executive having engaged in intentional misconduct that caused or
      would have caused, if the Company did not intervene, a serious violation
      by the Company of any state or federal laws, (2) the Executive having
      engaged in a theft of corporate funds or corporate assets or in a material
      act of fraud upon the Company, (3) an intentional act of personal
      dishonesty taken by the Executive that was intended to result in personal
      enrichment of the Executive at the expense of the Company, (4) repeated
      violations by the Executive of Executive's primary or regular obligations
      under this Agreement or under written policies of the Company which are
      demonstrably willful on the Executive's part, and for which Executive has
      received more than two written warnings that specify each area of
      Executive's violations, (5) Executive's use of illegal drugs as evidenced
      by a drug test authorized by Company, (6) Executive's final conviction (or
      the entry of a plea of nolo contendere or equivalent plea) in a court of
      competent jurisdiction of a felony or other crime involving dishonesty,
      and (7) a breach by the Executive during the Employment Period of the
      provisions of Sections 11, 12, 13 or 14 below, if such breach results in a
      material injury to the Company.

            "GOOD REASON" means the occurrence of any of the following events
      without Executive's express written consent:

                  (1) A ten percent (10%) or greater reduction in Executive's
            annual base salary; or

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                  (2) Any breach by the Company or its successors of any
            material provision of this Agreement; or

                  (3) A substantial and adverse change in the Executive's
            duties, control, authority, status or position, or the assignment to
            the Executive of any duties or responsibilities which are materially
            inconsistent with such status or position, or a material reduction
            in the duties and responsibilities previously exercised by the
            Executive, or a loss of title, loss of office, loss of significant
            authority, power or control, or any removal of Executive from, or
            any failure to reappoint or reelect him to, such positions, except
            in connection with the termination of his employment for Cause,
            Disability or death; or

                  (4) Following a Change in Control (as defined in Section 6(b))
            any of the following events:

                        (A) the failure by the Company or its successor to
                  expressly assume and agree to continue and perform this
                  Agreement in the same manner and to the same extent that the
                  Company would be required to perform if such Change in Control
                  had not occurred;

                        (B) a relocation of more than twenty-five (25) miles of
                  Executive's principal office from the location of such office
                  immediately prior to the Change in Control date;

                        (C) a substantial increase in the business travel
                  required of Executive by the Company or its successor; or

                        (D) the Company or its successor fails to continue in
                  effect any pension plan, health-and-accident plan, or
                  disability income plan in which Executive was participating at
                  the time of the Change in Control (or plans providing
                  Executive with substantially equal and similar benefits), or
                  the taking of any action by the Company or its successor which
                  would adversely affect Executive's participation in or
                  materially reduce his benefits under any such plan that was
                  enjoyed by him immediately prior to the Change in Control.

            (c) STOCK OPTIONS. In the event of a Change in Control, Executive's
      resignation for Good Reason or Executive's termination without Cause, all
      unvested stock options previously granted to Executive shall immediately
      vest and be exercisable as set forth below. In the event that there is a
      termination of Executive's employment hereunder for any reason, Executive
      shall be entitled to exercise any and all stock options that were
      previously granted

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      to him by the Company, and are outstanding, vested and unexercised as of
      his Termination Date, during the exercise period ending on the shorter of
      (i) two (2) years from his Termination Date or (ii) the expiration date of
      the stock option as specified in the stock option plan or stock option
      agreement, as applicable, notwithstanding any provision in such plan or
      agreement that provides for a more limited time period to exercise stock
      options following termination of employment; provided however, if said
      stock option plan or stock option agreement provides therein for a longer
      period of time to exercise such outstanding, vested and unexercised stock
      options following his Termination Date, then such stock option plan or
      agreement shall control and the remaining provisions of this Section 6(c)
      shall be inapplicable and without further force or effect. In the event
      that there is a termination of Executive's employment hereunder for Cause
      or Executive voluntarily resigns without Good Reason within two years for
      the date of this Agreement, Executive shall forfeit any and all stock
      options that were previously granted to him by the Company, and are
      unvested and unexercised as of his Termination Date.

            During the extension period specified in the previous paragraph, if
      applicable, the Executive shall be considered an employee of the Company
      who shall make himself available to provide consulting services to the
      Company in consideration for such extension of the option exercise period
      and any post-termination payments provided to Executive under Section 6(a)
      or (b) of this Agreement. In this regard, Executive agrees to be
      classified as an employee of the Company solely for the limited purpose of
      making himself available to provide consulting services on an as-needed
      basis; provided, however, Executive hereby specifically waives any right,
      entitlement, claim or demand to (i) any additional compensation for such
      consulting services and (ii) coverage or benefits under any of the
      Company's employee benefit plans or programs, or other perquisites, terms
      and conditions of employment, except as expressly specified in other
      provisions of this Agreement. Except as expressly provided in this Section
      6(c), the provision of consulting services by Executive shall not expand
      his rights or duties under this Agreement. Executive hereby agrees to
      provide, upon request of the Company, consulting services to the Company
      on the following terms and conditions:

            (1)   Executive will make himself available, on an as-needed basis,
                  to provide consulting services to the Company for up to three
                  (3) days per month during the period beginning on the day
                  after his Termination Date and ending on the last day of the
                  extension period for exercising stock options as provided in
                  the first paragraph of Section 6(c) above, subject to the
                  following conditions:

                  (A)   At least five (5) days written advance notice to
                        Executive is provided by the Company;

                  (B)   There is no concurrent illness of Executive or his
                        spouse;

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                  (C)   There is no prior commitment of Executive including,
                        without limitation, vacation or attention to personal
                        affairs; and

                  (D)   No travel is required of Executive in excess of 200
                        miles round-trip.

                  Executive, in any particular instance, may waive any or all of
                  the conditions set forth in clauses (A), (B), (C) or (D) above
                  in his complete discretion. Any such waiver shall not be a
                  continuing waiver and shall not release Executive of any of
                  his rights hereunder.

            (2)   Executive agrees to provide such information, services, advice
                  and recollection of events as may from time to time be
                  reasonably requested by, or on behalf of, the Company
                  regarding corporate, regulatory or business matters of which
                  Executive may have knowledge, information or understanding,
                  including testifying truthfully in any litigation or other
                  proceedings involving the Employer, provided that (i)
                  Executive first determines that his interests are not adverse,
                  or potentially adverse, to those of the Company, and (ii) the
                  Company has indemnified Executive to his satisfaction
                  including, without limitation, for reasonable attorney's fees
                  and costs. The parties hereto agree that it is the quality,
                  and not the quantity, of the consulting services to be
                  provided by Executive that is important to the Company.

            (3)   The Company will reimburse Executive for all reasonable
                  out-of-pocket expenses incurred by Executive in the course of
                  his performance of consulting services, including, without
                  limitation, supplies, mileage and travel expenses. Executive
                  agrees not to incur any expense, obligation, or liability on
                  behalf of the Company without its prior written consent.

            (4)   The provision of consulting services by Executive for the
                  Company is non-exclusive and shall not, in any way, limit the
                  rights of Executive to seek and maintain other employment or
                  to perform compensatory services on behalf of any other person
                  or entity.

            (5)   The consulting services contemplated under this Section 6(c)
                  shall not be considered part of Executive's Employment Period
                  pursuant to Section 4, nor affect his Termination Date.

      7. NOTICE OF TERMINATION. Any termination by the Company or the Executive
shall be communicated by Notice of Termination to the other party hereto. For
purposes of this Agreement,

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the term "NOTICE OF TERMINATION" means a written notice which indicates the
specific termination provision of this Agreement relied upon and sets forth in
reasonable detail the facts and circumstances claimed to provide a basis for
termination of the Executive's employment under the provision so indicated.

      8. NO MITIGATION REQUIRED. Executive shall not be required to mitigate the
amount of any payment provided for under this Agreement by seeking other
employment or in any other manner.

      9. CHANGE IN CONTROL: REQUIREMENT OF BONUS PAYMENT IN CERTAIN
CIRCUMSTANCES.

            (a) In the event that Executive is deemed to have received an
      "excess parachute payment" (as such term is defined in Section 280G(b) of
      the Code) which is subject to the excise taxes (the "EXCISE TAXES")
      imposed by Section 4999 of the Code in respect of any payment pursuant to
      this Agreement, or any other agreement, plan, instrument or obligation, in
      whatever form, the Company shall make the Bonus Payment (defined below) to
      Executive promptly after the date on which Executive received or is deemed
      to have received any excess parachute payment notwithstanding any contrary
      provision herein.

            (b) The term "BONUS PAYMENT" means a cash payment in an amount equal
      to the sum of (i) all Excise Taxes payable by Executive, plus (ii) all
      additional Excise Taxes and federal or state income taxes to the extent
      such taxes are imposed in respect of the Bonus Payment, such that
      Executive shall be in the same after-tax position and shall have received
      the same benefits that he would have received if the Excise Taxes had not
      been imposed. For purposes of calculating any income taxes attributable to
      the Bonus Payment, Executive shall be deemed for all purposes to be paying
      income taxes at the highest marginal federal income tax rate, taking into
      account any applicable surtaxes and other generally applicable taxes which
      have the effect of increasing the marginal federal income tax rate and, if
      applicable, at the highest marginal state income tax rate, to which the
      Bonus Payment and Executive are subject. An example of the calculation of
      the Bonus Payment is set forth below: Assume that the Excise Tax rate is
      20%, the highest federal marginal income tax rate is 40% and Executive is
      not subject to state income taxes. Further assume that Executive has
      received an excess parachute payment in the amount of $200,000, on which
      $40,000 in Excise Taxes are payable. The amount of the required Bonus
      Payment is thus $100,000. The Bonus Payment of $100,000, less additional
      Excise Taxes on the Bonus Payment of $20,000 (i.e., 20% x $100,000) and
      income taxes of $40,000 (i.e., 40% x $100,000), yields $40,000, the amount
      of the Excise Taxes payable in respect of the original excess parachute
      payment.

            (c) Executive agrees to reasonably cooperate with the Company to
      minimize the amount of the excess parachute payments, including, without
      limitation, assisting the Company in establishing that some or all of the
      payments received by Executive that are

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      "contingent on a change", as described in Section 280G(b)(2)(A)(i) of the
      Code, are reasonable compensation for personal services actually rendered
      by Executive before the date of such change or to be rendered by Executive
      on or after the date of such change. In the event that the Company is able
      to establish that the amount of the excess parachute payments is less than
      originally anticipated by Executive, Executive shall refund to the Company
      any excess Bonus Payment to the extent not required to pay Excise Taxes or
      income taxes (including those incurred in respect of receipt of the Bonus
      Payment). Notwithstanding the foregoing, Executive shall not be required
      to take any action which his attorney or tax advisor advises him in
      writing (i) is improper or (ii) exposes Executive to material personal
      liability. Executive may require the Company to deliver to Executive an
      indemnification agreement in form and substance satisfactory to Executive
      as a condition to taking any action required by this subsection (c).

            (d) The Company shall make any payment required to be made under
      this Section 9 in cash and on demand. Any payment required to be paid by
      the Company under this Section 9 which is not paid within 30 days of
      receipt by the Company of Executive's written demand therefor shall
      thereafter be deemed delinquent, and the Company shall pay to Executive
      immediately upon demand interest at the highest nonusurious rate per annum
      allowed by applicable law from the date such payment becomes delinquent to
      the date of payment of such delinquent sum with interest.

            (e) In the event that there is any change to the Code which results
      in the recodification of Section 280G or Section 4999 of the Code, or in
      the event that either such section of the Code is amended, replaced or
      supplemented by other provisions of the Code of similar import ("SUCCESSOR
      PROVISIONS"), then this Agreement shall be applied and enforced with
      respect to such new Code provisions in a manner consistent with the intent
      of the parties as expressed herein, which is to assure that Employee is in
      the same after-tax position and has received the same benefits that he
      would have been in and received if any taxes imposed by Section 4999 or
      any Successor Provisions had not been imposed.

      10. POST-TERMINATION MEDICAL COVERAGE. If the employment of Executive is
terminated for any reason except for Cause (as defined in Section 6(b)), death
or voluntary resignation without Good Reason, then the Company shall provide
post-employment medical coverage in accordance with the terms and conditions of
this Section 10. The Company shall continue to cover Executive and his spouse
(hereinafter referred to as "SPOUSE") and his eligible dependent children, if
any, from the Termination Date until two (2) years following the Termination
Date, under the group health care plan maintained by the Company to provide
major medical insurance coverage for employees and their dependents (such group
medical plan or its successor shall be hereinafter referred to as the "HEALTH
CARE PLAN").

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      Executive, on behalf of himself and his Spouse and other dependents, if
any, shall be required to pay premiums for their coverage under the Health Care
Plan at the rates, if any, charged by the Company to active employees who are
senior officers of the Company at the time the premium is charged. Any
post-employment coverage under the Health Care Plan provided under this Section
10 shall run concurrently with COBRA continuation coverage under the Health Care
Plan and, therefore, Executive and the other qualifying beneficiaries shall
elect any COBRA continuation coverage offered to them under the Health Care Plan
following the Termination Date. The Company shall not be responsible for the
payment of any income or other taxes which may be imposed on Executive, or on
his Spouse or dependents, as the result of receiving coverage under the Health
Care Plan pursuant to this Section 10.

      Executive, on behalf of himself and his Spouse and dependents, hereby
agrees and consents to acquire and maintain any coverage that of any them are
entitled to at any time during the two year period (as specified above in this
Section 10) under the Medicare program or any similar or succeeding plan or
program that is sponsored or maintained by the United States Government or any
agency thereof (hereinafter referred to as "MEDICARE"). The coverage described
in the immediately preceding sentence includes, without limitation, parts A and
B of Medicare and any additional or successor parts of Medicare. Executive, on
behalf of himself and his Spouse, further agrees and consents to pay all
required premiums and other costs for Medicare coverage from their personal
funds. Medicare coverage shall be primary payor to the coverage provided under
the Health Care Plan to the extent permitted by applicable federal law.

      11. CONFLICTS OF INTEREST. In keeping with his fiduciary duties to
Company, Executive hereby agrees that he shall not become involved in a conflict
of interest, or upon discovery thereof, allow such a conflict to continue at any
time during the Employment Period. Moreover, Executive agrees that he shall
immediately disclose to the Board of Directors any facts that might involve a
conflict of interest that has not been approved by the Board of Directors.

      Executive and Company recognize and acknowledge that it is not possible to
provide an exhaustive list of actions or interests that may constitute a
"conflict of interest." Moreover, Company and Executive recognize there are many
borderline situations. In some instances, full disclosure of facts by the
Executive to the Board of Directors may be all that is necessary to enable
Company to protect its interests. In others, if no improper motivation appears
to exist and Company's interests have not demonstrably suffered, prompt
elimination of the outside interest may suffice. In other egregious instances,
it may be necessary for Company to terminate Executive's employment for Cause
pursuant to Section 6(b) hereof. The Board of Directors reserves the right to
take such action as, in its good faith judgment, will resolve the conflict of
interest.

      Executive hereby agrees that any direct or indirect interest in,
connection with, or benefit from any outside activities, particularly commercial
activities, which interest might adversely affect the Company or any of its
affiliated entities, involves a possible conflict of interest. Circumstances

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in which a conflict of interest on the part of Executive would or might arise,
and which should be reported immediately to the Board of Directors, include, but
are not limited to, any of the following:

            (a) Ownership of more than a de minimis interest in any lender,
      supplier, contractor, customer or other entity with which Company or any
      of its affiliated entities does business;

            (b) Misuse of information, property or facilities to which Executive
      has access in a manner which is demonstrably injurious to the interests of
      Company or any of its affiliated entities, including its business,
      reputation or goodwill; or

            (c) Materially trading in products or services connected with
      products or services designed or marketed by or for the Company or any of
      its affiliated entities.

      For purposes of this Agreement, "AFFILIATED ENTITY" means any entity which
owns or controls, is owned or controlled by, or is under common ownership or
control with, the Company.

      12. CONFIDENTIAL INFORMATION.

      (a) CONFIDENTIAL INFORMATION DEFINED. Executive hereby acknowledges that
in his senior management position, he will create, acquire and have access to
confidential information and trade secrets pertaining to the business of Company
(hereafter "Confidential Information" as defined below). Executive hereby
acknowledges that such Confidential Information is unique and valuable to
Company's business and that Company would suffer irreparable injury if
Confidential Information was divulged to the public or to persons or entities in
competition with Company. Therefore, Executive hereby covenants and agrees to
keep in strict secrecy and confidence, both during and after the Employment
Period, any Confidential Information. Executive specifically agrees that he will
not at any time disclose to others, use, copy or permit to be copied, except in
pursuance of his duties on behalf of Company or with the prior consent of
Company, Confidential Information relating to the Company or any of its
affiliated entities. For purposes of this Agreement, "CONFIDENTIAL INFORMATION"
shall mean and include, without limitation, information related to the business
affairs, property, methods of operation, future plans, financial information,
customer or client information, or other data which relates to the business or
operations of Company or any of its affiliated entities, and all other
information obtained by Executive from and during the Employment Period which
concerns the affairs of Company or any of its affiliated entities and which
Company has requested be held in confidence or could reasonably be expected to
desire be held in confidence, or the disclosure of which would likely be
embarrassing, detrimental or disadvantageous to the Company or any of its
affiliated entities, or its and their directors, officers, employees or
shareholders. Confidential Information, however, shall not include information
that is at the time of receipt by Executive in the public domain or is otherwise
generally known in the industry or subsequently enters the public domain or
becomes generally known in the industry through no fault of Executive or breach
of his duty under this Section 12.

                                       12
<PAGE>   13
            (b) REQUIRED DISCLOSURE. In the event that Executive is required by
      law which cannot be waived to disclose any Confidential Information,
      Executive agrees that he will provide prompt notice of such potential
      disclosure to Company so that an appropriate protective order may be
      sought and/or a waiver of compliance with the provisions of this Agreement
      may be granted. In the event that (i) such protection or other remedy is
      not obtained or (ii) Company waives in writing the compliance by Executive
      with this provision, Executive agrees that he may furnish only that
      portion of the Confidential Information which Executive is advised by
      written opinion of counsel is legally required to be disclosed, and
      Executive shall exercise his best efforts to obtain assurances that
      confidential treatment will be accorded such Confidential Information.

            (c) DELIVERY OF DOCUMENTS. Executive further agrees to deliver to
      Company at the termination of his employment, all correspondence,
      memoranda, notes, records, drawings, plans, customer lists or other
      documents, and all copies thereof made, composed or received by Executive,
      solely or jointly with others, and which are in Executive's possession,
      custody or control at such date and which relate in any manner to the
      past, present or anticipated business of Company or any of its affiliated
      entities.

            (d) REMEDIES. In the event of a breach or threatened breach of any
      of the provisions of this Section 12, Company shall be entitled to an
      injunction ordering the return of all such documents, and any and all
      copies thereof, and restraining Executive from using or disclosing, for
      his benefit or the benefit of others, in whole or in part, any
      Confidential Information, including, but not limited to, the Confidential
      Information which such documents contain, constitute or embody. Executive
      further agrees that any breach or threatened breach of any of the
      provisions of this Section 12 would cause irreparable injury to Company,
      for which it would have no adequate remedy at law. Nothing herein shall be
      construed as prohibiting Company from pursuing any other remedies
      available to it for any such breach or threatened breach, including the
      recovery of damages.

      13. PROPERTY RIGHTS. In keeping with his fiduciary duties to Company,
Executive hereby covenants and agrees that during his Employment Period, and for
a period of one (1) year following his Termination Date, Executive shall
promptly disclose in writing to Company any and all information, ideas,
concepts, improvements, discoveries, inventions and other intellectual
properties, whether patentable or not, and whether or not reduced to practice,
which are conceived, developed, made or acquired by Executive, either
individually or jointly with others, and which relate to the business, products
or services of Company or any of its affiliated entities. In consideration for
his employment hereunder, Executive hereby specifically sells, assigns and
transfers to Company all of his worldwide right, title and interest in and to
all such information, ideas, concepts, improvements, discoveries, inventions and
other intellectual properties.

                                       13
<PAGE>   14
      If during the Employment Period, Executive creates any original work of
authorship or other property fixed in any tangible medium of expression which
(a) is the subject matter of copyright (including computer programs) and (b)
relates to Company's present or planned business, products, or services, whether
such property is created solely by Executive or jointly with others, such
property shall be deemed a work for hire, with the copyright automatically
vesting in Company. To the extent that any such writing or other property is
determined not to be a work for hire for whatever reason, Executive hereby
consents and agrees to the unconditional waiver of "moral rights" in such
writing or other property, and to assign to Company all of his right, title and
interest, including copyright, in such writing or other property.

      Executive hereby agrees to (a) assist Company or its nominee at all times
in the protection of any and all property subject to this Section 13, (b) not to
disclose any such property to others without the written consent of Company or
its nominee, except as required by his employment hereunder, and (c) at the
request of Company, to execute such assignments, certificates or other interests
as Company or its nominee may from time to time deem desirable to evidence,
establish, maintain, perfect, protect or enforce its rights, title or interests
in or to any such property.

      14. AGREEMENT NOT TO COMPETE. Executive hereby recognizes and acknowledges
that: (a) in his executive capacity with Company he will be given knowledge of,
and access to, the Confidential Information (as described in Section 12); (b) in
the event that Executive was to enter into competition with Company, Executive's
knowledge of such Confidential Information would be of invaluable benefit to a
competitor of Company, and could cause irreparable harm to Company's business
interests; and (c) Executive's consent and agreement to enter into the
noncompetition provisions and covenants set forth herein is an integral
condition of this Agreement, without which Company would not have agreed to
provide Confidential Information to Executive, nor to his compensation,
benefits, and other terms of this Agreement. Accordingly, in consideration for
his employment, compensation, benefits, access to and entrustment of
Confidential Information, the goodwill, training and experience provided to
Executive during his Employment Period, Executive hereby covenants, consents and
agrees (regardless of whether or not there has been a Change of Control) that
during the Employment Period, and for a period two (2) years after his
employment is terminated for any reason, Executive shall not, directly or
indirectly, acting alone or in conjunction with others, for his own account or
for the account of others, including, without limitation, as an officer,
director, stockholder, owner, partner, member, manager, joint venturer,
employee, promoter, consultant, agent, lender, guarantor, representative, or
otherwise:

            (a) Solicit, canvass, or accept any fees or business from any
      customer of Company for himself or any other person or entity engaged in a
      "Similar Business to Company" (as defined below);

            (b) Engage or participate in any Similar Business to Company within
      any states of the United States in which the Company transacts business on
      Executive's termination of

                                       14
<PAGE>   15
      employment date, or in which, as of such termination date, the Company has
      made any plans or proposals to transact business within one year from such
      termination date (referred to herein as the "RESTRICTED AREA");

            (c) Request or advise any service provider, supplier, or customer to
      reduce or cancel any business that it may transact with Company or any of
      its affiliated entities;

            (d) Solicit, induce, or otherwise attempt to influence any employee
      of the Company or any of its affiliated entities, to terminate his or her
      relationship with the Company or any of its affiliated entities; or

            (e) Make any statement or perform any act intended to advance an
      interest of an existing or prospective competitor of the Company or any of
      its affiliated entities in any way that demonstrably injures the
      reputation, goodwill or any other business interest of Company or any of
      its affiliated entities.

      For purposes of this Agreement, "SIMILAR BUSINESS TO COMPANY" means any
business or other enterprise that is competitive with the current or planned
businesses, products, services or operations of the Company or any of its
affiliated entities at the time of termination of Executive's employment
including, without limitation, municipal biosolids.

      Executive hereby agrees that the limitations set forth above on his rights
to compete with Company after his termination of employment are reasonable and
necessary for the protection of Company. In this regard, Executive specifically
agrees that such limitations as to the period of time, geographic area and types
and scopes of restriction on his activities, as specified above, are reasonable
and necessary to protect the goodwill and other business interests of Company.
However, should the time period, the geographic area or any other
non-competition provision set forth herein be deemed invalid or unenforceable in
any respect, then Executive acknowledges and agrees that, as set forth in
Section 15 hereof, reformation may be made with respect to such time period,
geographic area or other non-competition provision in order to protect Company's
reasonable business interests to the maximum permissible extent.

      15. REMEDIES. In the event of any pending, threatened or actual breach of
any of the covenants or provisions of Section 11, 12, 13 or 14, it is understood
and agreed by Executive that the remedy at law for a breach of any of the
covenants or provisions of these Sections may be inadequate, and, therefore,
Company shall be entitled to a restraining order or injunctive relief from any
court of competent jurisdiction, in addition to any other remedies at law and in
equity. In the event that Company seeks to obtain a restraining order or
injunctive relief, Executive hereby agrees that Company shall not be required to
post any bond in connection therewith. Should a court of competent jurisdiction
or an arbitrator (pursuant to Section 24) declare any provision of Section 11,
12, 13 or 14 to be unenforceable due to an unreasonable restriction of duration
or geographical area,

                                       15
<PAGE>   16
or for any other reason, such court or arbitrator is hereby granted the consent
of each of Executive and the Company to reform such provision and/or to grant
the Company any relief, at law or in equity, reasonably necessary to protect the
reasonable business interests of Company or any of its affiliated entities.
Executive hereby acknowledges and agrees that all of the covenants and other
provisions of Sections 11, 12, 13 and 14 are reasonable and necessary for the
protection of the Company's reasonable business interests. Executive hereby
agrees that if the Company prevails in any action, suit or proceeding with
respect to any matter arising out of or in connection with Section 11, 12, 13 or
14, Company shall be entitled to all equitable and legal remedies, including,
but not limited to, injunctive relief and compensatory damages.

      16. DEFENSE OF CLAIMS. Executive agrees that, during the Employment Period
and for a period of two (2) years after his Termination Date, upon reasonable
request from the Company, he will cooperate with the Company and its affiliated
entities in the defense of any claims or actions that may be made by or against
the Company or any of its affiliated entities that affect his prior areas of
responsibility, except if Executive's reasonable interests are adverse to the
Company (or affiliated entity) in such claim or action. To the extent travel is
required to comply with the requirements of this Section 16, the Company shall,
to the extent possible, provide Executive with notice at least 10 days prior to
the date on which such travel would be required. The Company agrees to promptly
pay or reimburse Executive upon demand for all of his reasonable travel and
other direct expenses incurred, or to be reasonably incurred, to comply with his
obligations under this Section 16.

      17. DETERMINATIONS BY THE BOARD OF DIRECTORS.

            (a) TERMINATION OF EMPLOYMENT. Prior to a Change in Control (as
      defined in Section 6(b)), any question as to whether and when there has
      been a termination of Executive's employment, and the cause of such
      termination, shall be determined by the Board of Directors in its
      discretion.

            (b) COMPENSATION. Prior to a Change in Control (as defined in
      Section 6(b)), any question regarding salary, bonus and other compensation
      payable to Executive pursuant to this Agreement shall be determined by the
      Board of Directors in its discretion.

      18 WITHHOLDINGS: RIGHT OF OFFSET. Company may withhold and deduct from any
benefits and payments made or to be made pursuant to this Agreement (a) all
federal, state, local and other taxes as may be required pursuant to any law or
governmental regulation or ruling, (b) all other normal employee deductions made
with respect to Company's employees generally, and (c) any advances made to
Executive and owed to Company.

      19 NONALIENATION. The right to receive payments under this Agreement shall
not be subject in any manner to anticipation, alienation, sale, transfer,
assignment, pledge or encumbrance by Executive, his dependents or beneficiaries,
or to any other person who is or may become entitled

                                       16
<PAGE>   17
to receive such payments hereunder. The right to receive payments hereunder
shall not be subject to or liable for the debts, contracts, liabilities,
engagements or torts of any person who is or may become entitled to receive such
payments, nor may the same be subject to attachment or seizure by any creditor
of such person under any circumstances, and any such attempted attachment or
seizure shall be void and of no force and effect.

      20 INCOMPETENT OR MINOR PAYEES. Should the Board of Directors determine
that any person to whom any payment is payable under this Agreement has been
determined to be legally incompetent or is a minor, any payment due hereunder
may, notwithstanding any other provision of this Agreement to the contrary, be
made in any one or more of the following ways: (a) directly to such minor or
person; (b) to the legal guardian or other duly appointed personal
representative of the person or estate of such minor or person; or (c) to such
adult or adults as have, in the good faith knowledge of the Board of Directors,
assumed custody and support of such minor or person; and any payment so made
shall constitute full and complete discharge of any liability under this
Agreement in respect to the amount paid.

      21 SEVERABILITY. It is the desire of the parties hereto that this
Agreement be enforced to the maximum extent permitted by law, and should any
provision contained herein be held unenforceable by a court of competent
jurisdiction or arbitrator (pursuant to Section 24), the parties hereby agree
and consent that such provision shall be reformed to create a valid and
enforceable provision to the maximum extent permitted by law; provided, however,
if such provision cannot be reformed, it shall be deemed ineffective and deleted
here from without affecting any other provision of this Agreement.

      22 TITLE AND HEADINGS; CONSTRUCTION. Titles and headings to Sections
hereof are for the purpose of reference only and shall in no way limit, define
or otherwise affect the provisions hereof. Any and all Exhibits referred to in
this Agreement are, by such reference, incorporated herein and made a part
hereof for all purposes. The words "herein", "hereof", "hereunder" and other
compounds of the word "here" shall refer to the entire Agreement and not to any
particular provision hereof.

      23 CHOICE OF LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS, WITHOUT REGARD TO THE PRINCIPLES
OF CONFLICTS OF LAW.

      24 ARBITRATION.

            (a) ARBITRABLE MATTERS. If any dispute or controversy arises between
      Executive and the Company as to their respective rights or obligations
      under this Agreement, then either party may submit the dispute or
      controversy to arbitration under the then-current National Employment
      Dispute Resolution Rules of the American Arbitration Association

                                       17
<PAGE>   18
      (AAA) (the "RULES"); provided, however, the Company shall retain its
      rights to seek a restraining order or injunctive relief pursuant to
      Section 15. Any arbitration hereunder shall be conducted before a single
      arbitrator unless the parties mutually agree to a panel of three
      arbitrators. The site for any arbitration hereunder shall be in Montgomery
      County or Harris County, Texas, unless otherwise mutually agreed by the
      parties.

            (b) SUBMISSION TO ARBITRATION. The party submitting any matter to
      arbitration shall do so in accordance with the Rules. Notice to the other
      party shall state the question or questions to be submitted for decision
      or award by arbitration. Notwithstanding any provision in this Section 24,
      Executive shall be entitled to seek specific performance of the
      Executive's right to be paid during the pendency of any dispute or
      controversy arising under this Agreement. In order to prevent irreparable
      harm, the arbitrator may grant temporary or permanent injunctive or other
      equitable relief for the protection of property rights.

            (c) ARBITRATION PROCEDURES. The arbitrator shall set the date, time
      and place for each hearing, and shall give the parties advance written
      notice in accordance with the Rules. Any party may be represented by
      counsel or other authorized representative at any hearing. The arbitration
      shall be governed by the Federal Arbitration Act, 9 U.S.C. Sections 1 et.
      seq. (or its successor). The arbitrator shall apply the substantive law
      (and the law of remedies, if applicable) of the State of Texas to the
      claims asserted to the extent that the arbitrator determines that federal
      law is not controlling.

            (d) COMPLIANCE WITH AWARD.

                  (1) Any award of an arbitrator shall be final and binding upon
            the parties to such arbitration, and each party shall immediately
            make such changes in its conduct or provide such monetary payment or
            other relief as such award requires. The parties agree that the
            award of the arbitrator shall be final and binding and shall be
            subject only to the judicial review permitted by the Federal
            Arbitration Act.

                  (2) The parties hereto agree that the arbitration award may be
            entered with any court having jurisdiction and the award may then be
            enforced as between the parties, without further evidentiary
            proceedings, the same as if entered by the court at the conclusion
            of a judicial proceeding in which no appeal was taken. The Company
            and the Executive hereby agree that a judgment upon any award
            rendered by an arbitrator may be enforced in other jurisdictions by
            suit on the judgment or in any other manner provided by law.

            (e) COSTS AND EXPENSES. Each party shall pay any monetary amount
      required by the arbitrator's award, and the fees, costs and expenses for
      its own counsel, witnesses and exhibits, unless otherwise determined by
      the arbitrator in the award. The compensation and

                                       18
<PAGE>   19
      costs and expenses assessed by the arbitrator and AAA shall be paid by the
      losing party unless otherwise determined by the arbitrator in the award.
      If court proceedings to stay litigation or compel arbitration are
      necessary, the party who unsuccessfully opposes such proceedings shall pay
      all associated costs, expenses, and attorney's fees which are reasonably
      incurred by the other party as determined by the arbitrator.

      25 BINDING EFFECT: THIRD PARTY BENEFICIARIES. This Agreement shall be
binding upon and inure to the benefit of the parties hereto, and to their
respective heirs, executors, personal representatives, successors and permitted
assigns hereunder, but otherwise this Agreement shall not be for the benefit of
any third parties.

      26 ENTIRE AGREEMENT AND AMENDMENT. This Agreement contains the entire
agreement of the parties with respect to Executive's employment and the other
matters covered herein; moreover, this Agreement supersedes all prior and
contemporaneous agreements and understandings, oral or written, between the
parties hereto concerning the subject matter hereof. This Agreement may be
amended, waived or terminated only by a written instrument executed by both
parties hereto.

      27 SURVIVAL OF CERTAIN PROVISIONS. Wherever appropriate to the intention
of the parties hereto, the respective rights and obligations of said parties,
including, but not limited to, the rights and obligations set forth in Sections
6 through 17 and 24 hereof, shall survive any termination or expiration of this
Agreement.

      28 WAIVER OF BREACH. No waiver by either party hereto of a breach of any
provision of this Agreement by any other party, or of compliance with any
condition or provision of this Agreement to be performed by such other party,
will operate or be construed as a waiver of any subsequent breach by such other
party or any similar or dissimilar provision or condition at the same or any
subsequent time. The failure of either party hereto to take any action by reason
of any breach will not deprive such party of the right to take action at any
time while such breach continues.

      29 SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon and inure
to the benefit of Company and its affiliated entities, and its and their
successors, and upon any person or entity acquiring, whether by merger,
consolidation, purchase of assets or otherwise, all or substantially all of the
assets and business of Company. Any reference herein to "Company" shall mean the
Company as first written above, as well as any successor or successors thereto.

      This Agreement is personal to Executive, and Executive may not assign,
delegate or otherwise transfer all or any of his rights, duties or obligations
hereunder without the consent of the Board of Directors. Any attempt by the
Executive to assign, delegate or otherwise transfer this Agreement, any portion
hereof, or his rights, duties or obligations hereunder without the prior written
consent of the Board of Directors shall be deemed void and of no force and
effect. Subject to the

                                       19
<PAGE>   20
preceding provisions of this paragraph, this Agreement shall be binding upon and
inure to the benefit of Executive and his heirs and assigns.

      30 NOTICES. Notices provided for in this Agreement shall be in writing and
shall be deemed to have been duly received (a) when delivered in person or sent
by facsimile transmission, (b) on the first business day after it is sent by air
express overnight courier service, or (c) on the third business day following
deposit in the United States mail, registered or certified mail, return receipt
requested, postage prepaid and addressed, to the following address, as
applicable:

            (1)   If to Company, addressed to:

                  Synagro Technologies, Inc.
                  5850 San Felipe, Suite 500
                  Houston, Texas 77057
                  Attention: CEO

            (2)   If to Executive, addressed to the address set forth below
                  his name on the execution page hereof;

or to such other address as either party may have furnished to the other party
in writing in accordance with this Section 30.

      31 COUNTERPARTS. This Agreement may be executed in any number of
counterparts, each of which when so executed and delivered shall be an original,
but all such counterparts shall together constitute one and the same instrument.
Each counterpart may consist of a copy hereof containing multiple signature
pages, each signed by one party hereto, but together signed by both of the
parties hereto.

      32 EXECUTIVE ACKNOWLEDGMENT/NO STRICT CONSTRUCTION. The Executive
represents to Company that he is knowledgeable and sophisticated as to business
matters, including the subject matter of this Agreement, that he has read the
Agreement and that he understands its terms and conditions. The parties hereto
agree that the language used in this Agreement shall be deemed to be the
language chosen by them to express their mutual intent, and no rule of strict
construction shall be applied against either party hereto. Executive also
represents that he is free to enter into this Agreement including, without
limitation, that he is not subject to any other contract of employment or
covenant not to compete that would conflict in any way with his duties under
this Agreement. Executive acknowledges that he has had the opportunity to
consult with counsel of his choice, independent of Employer's counsel, regarding
the terms and conditions of this Agreement and has done so to the extent that
he, in his unfettered discretion, deemed to be appropriate.

                                       20
<PAGE>   21
      33 SUPERSEDING AGREEMENT. This Employment Agreement shall supersede any
prior employment agreement entered into between the Company and Executive.

      IN WITNESS WHEREOF, the Executive has hereunto set his hand, and Company
has caused these presents to be executed in its name and on its behalf, to be
effective as of the Effective Date first above written.



WITNESS:                               EXECUTIVE:




Signature:                             Signature:
          -------------------------              -----------------------------

Printed Name:                          Printed Name: ALVIN L. THOMAS II
              ---------------------                  -------------------------

Date:                                  Date:
     ------------------------------         ----------------------------------

                                       Address for Notices:

                                       2342 Quenby Street
                                       Houston, Texas 77005


ATTEST:                                SYNAGRO TECHNOLOGIES, INC.:

By:                                    By:
   --------------------------------       ------------------------------------

Title:                                 Its:  CHAIRMAN & CEO
      -----------------------------

Printed Name:                          Printed Name: ROSS M. PATTEN
             ----------------------                  -------------------------

Date:                                  Date:
     ------------------------------         ----------------------------------

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