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                                                                    Exhibit 10.2

                              MANAGEMENT AGREEMENT

     THIS MANAGEMENT AGREEMENT (this "AGREEMENT"), dated as of May 18, 2004 is
made by and among CHS Management IV LP, a Delaware limited partnership ("CHS"),
GEO Holdings Corp., a Delaware corporation ("PARENT"), and Gundle/SLT
Environmental, Inc., a Delaware corporation (the "COMPANY").

     WHEREAS, Parent and the Company desire to receive financial and management
consulting services from CHS, and thereby obtain the benefit of the experience
of CHS in business and financial management generally and its knowledge of
Parent and the Company and Parent and the Company's financial affairs in
particular. CHS is willing to provide financial and management consulting
services to Parent and the Company. Accordingly, the compensation arrangements
set forth in this Agreement are designed to compensate CHS for such services.

     NOW, THEREFORE, in consideration of the foregoing premises and the
respective agreements hereinafter set forth and the mutual benefits to be
derived herefrom, CHS, Parent and the Company hereby agree as follows:

                                      TERMS

1.   ENGAGEMENT. Parent and the Company hereby engage CHS as a financial and
     management consultant, and CHS hereby agrees to provide financial and
     management consulting services to Parent and the Company, all on the terms
     and subject to the conditions set forth below.

2.   SERVICES OF CHS. CHS hereby agrees during the term of this engagement to
     consult with the boards of directors and the management of Parent and the
     Company in such manner and on such business and financial matters as may be
     reasonably requested from time to time by the boards of directors and the
     management of Parent and the Company, including but not limited to: (a)
     business strategy; (b) budgeting of future business investments; (c)
     acquisition and divestiture strategies; and (d) debt and equity financings.

3.   COMPENSATION.

     (a)  MONTHLY FEE. The Company agrees to pay to CHS as compensation for
          services to be rendered by CHS hereunder, a monthly fee equal to
          $166,666.66, payable monthly in arrears on the last day of each month,
          commencing with the month during which the closing of the Purchase (as
          defined below) occurs, with the monthly payment for the month in which
          the Purchase is closed being pro rated for the number of days between
          the date of such closing and the end of such month. Such fee shall be
          expressly subordinated to the principal, interest and premium, if any,
          owing under the Company's 11% Senior Notes due 2012 (the "SENIOR
          NOTES") and under the Credit Agreement (as such term is defined in the
          Indenture (as defined below)) until all obligations under the Senior
          Notes and the

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          Credit Agreement, including interest through the date of payment
          (whether or not such interest is allowed in a bankruptcy case), have
          been paid in full in cash; PROVIDED that, notwithstanding such
          subordination, such fee shall be permitted to be paid at all times
          other than during such time (a "RESTRICTED PERIOD") as either (i) a
          Default or an Event of Default (each such term as defined in the
          Indenture governing the Senior Notes (as such Indenture may be
          amended, restated, supplemented, renewed, replaced or otherwise
          modified from time to time, the "INDENTURE")) has occurred and is
          continuing with respect to the Senior Notes (it being understood that
          any such Default or Event of Default that results exclusively due to a
          default under the Credit Agreement shall not give rise under this
          clause (i) to the Restricted Period) or (ii) any Event of Default (as
          defined in the Credit Agreement) specified in any of Sections 8.01(a),
          8.01(b), 8.01(g) or 8.01(h) of the Credit Agreement has occurred and
          is continuing; PROVIDED further that the fee shall continue to accrue
          during any Restricted Period and all accrued and unpaid fees will be
          paid upon the termination of the Restricted Period. In the event that
          any amount of the fee specified in this paragraph is paid by the
          Company to CHS during a Restricted Period, CHS agrees to turn over
          such amount to the Collateral Agent under the Credit Agreement, to be
          held as additional Collateral for the Obligations under the Credit
          Agreement (all capitalized terms in this sentence not otherwise
          defined in this Agreement shall have the meanings provided in the
          Credit Agreement); PROVIDED that, pursuant to pursuant to Section
          11.4(b) of that certain Security Agreement, dated as of May 18, 2004,
          among the Company, the Guarantors party thereto and UBS AG, Stamford
          Branch, as Collateral Agent, the Company shall (and shall cause its
          subsidiaries and affiliates to) request the Collateral Agent to (and
          take other actions reasonably requested by CHS to cause the Collateral
          Agent to) return to CHS upon the end of the Restricted Period any
          amount so turned over; PROVIDED FURTHER that any amount turned over to
          the Collateral Agent and not returned to CHS upon the end of the
          applicable Restricted Period pursuant to the preceding proviso shall
          be deemed to have accrued and not been paid by the Company, and the
          Company shall pay CHS such unreturned amounts within 2 days after
          CHS's written request. Upon a termination of this Agreement in
          accordance with SECTION 5 hereof which does not occur on the last day
          of a month, a pro rated monthly fee shall be paid based upon the
          number of days elapsed in the partial month prior to termination.

     (b)  PURCHASE. As compensation for services rendered by CHS to Parent in
          connection with the identification and negotiation of the Plan and
          Agreement of Merger, dated as of December 31, 2003, by and among
          Parent, the Company and GEO Sub Corp. (the "Merger Agreement"), the
          structuring of the transactions contemplated by the Merger Agreement
          and the financing of such transactions (the "PURCHASE"), Holdings
          agrees to pay $5,000,000.00 to CHS on the date hereof.

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     (c)  FUTURE PURCHASES. When and as Code Hennessy & Simmons IV LP or any of
          its affiliates purchase equity securities of Parent, Parent will pay
          to CHS a fee equal to 5.0% of the gross purchase price of such
          securities as compensation for services rendered by CHS to Parent in
          connection with the consummation of the transaction or other activity
          giving rise to such purchase.

4.   EXPENSE REIMBURSEMENT. Parent and the Company, as applicable, shall
     promptly reimburse CHS for such reasonable travel expenses and other
     out-of-pocket fees and expenses as may be incurred by CHS, its partners and
     employees in connection with the Purchase and future acquisitions, and in
     connection with the rendering of services hereunder.

5.   TERM. This Agreement shall be in effect for an initial term of seven years
     commencing on the date hereof, and shall be automatically renewed
     thereafter on a year-to-year basis unless one party gives 30 days' prior
     written notice of its desire to terminate this Agreement; provided,
     however, that this Agreement shall terminate on a Sale of the Company (as
     defined in the Stockholders Agreement, dated as of the date hereof, by and
     among Parent, Code Hennessy & Simmons IV LP and Parent's other
     stockholders). No termination of this Agreement, whether pursuant to this
     paragraph or otherwise, shall affect Parent's or the Company's obligations
     with respect to the fees, costs and expenses incurred by CHS in rendering
     services hereunder and not reimbursed by Parent or the Company as of the
     effective date of such termination.

6.   INDEMNIFICATION. Parent and the Company agree, jointly and severally, to
     indemnify and hold harmless CHS, its officers and employees against and
     from any and all loss, liability, suits, claims, costs, damages and
     expenses (including attorneys' fees) arising from their performance
     hereunder, except as a result of their gross negligence or intentional
     wrongdoing.

7.   CHS AN INDEPENDENT CONTRACTOR. CHS, Parent and the Company agree that CHS
     shall perform services hereunder as an independent contractor, retaining
     control over and responsibility for its own operations and personnel.
     Neither CHS nor its partners or employees shall be considered employees or
     agents of Parent or the Company as a result of this Agreement nor shall any
     of them have authority to contract in the name of or bind Parent or the
     Company, except as expressly agreed to in writing by Parent or the Company,
     respectively.

8.   NOTICES. Any notice, report or payment required or permitted to be given or
     made under this Agreement by one party to the other shall be deemed to have
     been duly given or made if personally delivered or, if mailed, when mailed
     by registered or certified mail, postage prepaid, to the other party at the
     following addresses (or at such other address as shall be given in writing
     by one party to the other):

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     If to CHS:

            CHS Management IV LP
            10 South Wacker Drive
            Suite 3175
            Chicago, IL 60606
            Facsimile: (312) 876-3854
            Attn: Daniel J. Hennessy and Marcus J. George

     with a copy to:

            Kirkland & Ellis LLP
            200 East Randolph Drive
            Chicago, IL 60601
            Facsimile: (312) 861-2200
            Attn: Kevin R. Evanich, P.C.

     If to Parent or the Company:

            Gundle/SLT Environmental, Inc.
            19103 Gundle Road
            Houston, Texas 77073
            Facsimile: (281) 443-3399
            Attn: Samir T. Badawi

9.   ENTIRE AGREEMENT; MODIFICATION. This Agreement (a) contains the complete
     and entire understanding and agreement of CHS, Parent and the Company with
     respect to the subject matter hereof; (b) supersedes all prior and
     contemporaneous understandings, conditions and agreements, oral or written,
     express or implied, respecting the engagement of CHS in connection with the
     subject matter hereof; and, (c) subject to SECTION 13 below, may not be
     modified except by an instrument in writing executed by CHS, Parent and the
     Company.

10.  WAIVER OF BREACH. The waiver by a party of a breach of any provision of
     this Agreement by another party shall not operate or be construed as a
     waiver of any subsequent breach of that provision or any other provision
     hereof.

11.  ASSIGNMENT. None of CHS, Parent or the Company may assign its rights or
     obligations under this Agreement without the express written consent of
     each other party.

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12.  CHOICE OF LAW. This Agreement shall be governed by and construed in
     accordance with the domestic laws of the State of Illinois, without giving
     effect to any choice of law or conflict of law provision or rule (whether
     of the State of Illinois or any other jurisdiction) that would cause the
     application of the laws of any jurisdiction other than the State of
     Illinois.

13.  THIRD PARTY BENEFICIARIES. Each of the Collateral Agent and the
     Administrative Agent (as each such term is defined in the Credit Agreement)
     and the Trustee (as such term is defined in the Indenture) shall be third
     party beneficiaries of the second and third sentences in SECTION 3(a)
     above. Any modification of such sentences shall require the consent of such
     Collateral Agent, such Administrative Agent and such Trustee.

                                     *   *   *   *

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     IN WITNESS WHEREOF, the parties hereto have caused this Management
Agreement to be duly executed and delivered on the date and year first above
written.

                                            CHS MANAGEMENT IV LP

                                            By:   Code Hennessy & Simmons LLC
                                            Its:  General Partner

                                            By:    /s/ DANIEL J. HENNESSY
                                                  ---------------------------
                                            Name:      Daniel J. Hennessy
                                                  ---------------------------
                                            Its:       Partner
                                                  ---------------------------


                                            GEO HOLDINGS CORP.

                                            By:    /s/ DANIEL J. HENNESSY
                                                  ---------------------------
                                            Name:      Daniel J. Hennessy
                                                  ---------------------------
                                            Its:       President
                                                  ---------------------------


                                            GUNDLE/SLT ENVIRONMENTAL, INC.

                                            By:    /s/ SAMIR T. BADAWI
                                                  ---------------------------
                                            Name:      Samir T. Badawi
                                                  ---------------------------
                                            Its:       President and Chief
                                                       Executive Officer
                                                  ---------------------------