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                                                                   EXHIBIT 10.11

                               FIRST AMENDMENT TO
                             REIMBURSEMENT AGREEMENT

      THIS FIRST AMENDMENT TO REIMBURSEMENT AGREEMENT (this "Amendment"), dated
as of April 28, 2005, is executed by and among WCA WASTE SYSTEMS, INC., a
Delaware corporation (the "Borrower"), WASTE CORPORATION OF TEXAS, L.P., a
Delaware limited partnership (the "Account Party"), and WELLS FARGO BANK,
NATIONAL ASSOCIATION, a national banking association (successor by merger to
Wells Fargo Bank Texas, National Association), as issuing bank under the
Agreement as defined hereinafter (in such capacity, the "Issuing Bank").

                                   RECITALS:

      A. The Borrower, the Account Party and the Issuing Bank executed that
certain Reimbursement Agreement dated as of August 30, 2002 (as the same has
been amended, modified, supplemented and restated from time to time, the
"Agreement").

      B. The Borrower, the Account Party, and the Issuing Bank desire to amend
the Agreement as described herein, subject to the terms and conditions contained
herein.

      NOW, THEREFORE, in consideration of the premises herein contained and
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto agree as follows intending to be legally
bound (all provisions of this Amendment being effective as of the date hereof
unless otherwise stated herein):

                                   ARTICLE I

                                  Definitions

      Section 1.1 Definitions. Capitalized terms used in this Amendment, to the
extent not otherwise defined herein, shall have the same meanings as in the
Agreement, as amended hereby.

                                   ARTICLE II

                            Amendments to Agreement

      Section 2.1 Amendment to Section 3(a). Effective as of the date hereof,
Section 3(a) of the Agreement is amended and restated in its entirety to ready
as follows:

            (a) Quarterly Redemption of Bonds. Borrower and Account Party
      covenant to take all necessary action to prepay the Installment Payments
      and cause optional redemptions of the Bonds pursuant to Section 3.01(b) of
      the Indenture and this Section 3 at a price equal to the principal amount
      of the Bonds to be redeemed, together with accrued interest to the
      redemption date, on the Quarterly Dates, commencing with June 1, 2005. The
      principal amounts of Bonds to be redeemed on each such Quarterly Date
      shall be as follows:

                                       1

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<TABLE>
<CAPTION>
 Quarterly Date:               Amount:
-----------------             --------
<S>                           <C>
   June 1, 2005               $300,000
September 1, 2005             $300,000
 December 1, 2005             $300,000
  March 1, 2006               $300,000
   June 1, 2006               $300,000
September 1, 2006             $300,000
 December 1, 2006             $400,000
  March 1, 2007               $300,000
   June 1, 2007               $300,000
September 1, 2007             $300,000
 December 1, 2007             $300,000
  March 1, 2008               $300,000
   June 1, 2008               $300,000
September 1, 2008             $300,000
 December 1, 2008             $400,000
  March 1, 2009               $300,000
   June 1, 2009               $300,000
September 1, 2009             $300,000
 December 1, 2009             $300,000
  March 1, 2010               $300,000
</TABLE>

            Notwithstanding the foregoing, Issuing Bank reserves the right to
      modify the amount of the principal payments on the Bonds to be redeemed on
      each Quarterly Date if Issuing Bank determines that the actual use of the
      proceeds of the Bonds have been materially different from the use of the
      proceeds of the Bonds as provided in the budget furnished to Issuing Bank
      prior to the date of this Agreement.

      Section 2.2 Amendment to Definitions of in Section 19. Effective as of the
date hereof, the following definitions in Section 19 of the Agreement are
amended and restated in their entirety to read as follows:

            "Credit Agreement" shall mean that certain First Lien Credit
      Agreement dated as of April 28, 2005 by and among Borrower, the lenders
      party thereto from time to time, and Wells Fargo Bank, National
      Association, as Administrative Agent, the Collateral Agent and as Issuing
      Bank, as the same may be amended,

                                       2

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      restated, supplemented or modified from time to time. On April 28, 2005
      the Expiration Date (as defined in the Letter of Credit) is March 30,
      2010.

            "Letter of Credit" shall mean Issuing Bank's irrevocable direct-pay
      Letter of Credit No. NZS453090 dated August 30, 2002 in favor of the
      Trustee, as may be extended, together with any amendments thereto and any
      substitutions thereof.

            "Security Instruments" shall mean the Security Agreements and other
      Loan Documents as such terms are defined in the Credit Agreement.

                                  ARTICLE III

                              Conditions Precedent

      Section 3.1 Condition. The effectiveness of this Amendment is subject to
the satisfaction of the following conditions precedent:

            (a) Amendment. The Issuing Bank shall have received this Amendment
      executed by the Borrower, the Account Party, and the Issuing Bank.

            (b) Credit Agreement. The Issuing Bank shall have received the
      Credit Agreement executed by the Borrower, the Issuing Bank and the other
      lenders party thereto.

            (c) Other Documents. Such other documents, agreements, and
      instruments as the Issuing Bank may reasonably request.

            (d) No Event of Default. No Default or Event of Default shall have
      occurred and be continuing.

            (e) Representations and Warranties. All of the representations and
      warranties contained in Section 8 of the Agreement and in the other Loan
      Documents shall be true and correct on and as of the date of this
      Amendment with the same force and effect as if such representations and
      warranties had been made on and as of such date, except to the extent such
      representations and warranties speak to a specific date.

            (f) Amendment Fee. Payment of an amendment fee in the amount of
      $1,000 to the Issuing Bank, which amendment fee will be due and payable as
      of the date hereof.

            (g) Conditions Precedent in Related Documents. All conditions
      precedent to the extension of the Letter of Credit in the Related
      Documents shall have been satisfied.

                                   ARTICLE IV

                  Ratifications, Representations and Warranties

      Section 4.1 Ratifications. The terms and provisions set forth in this
Amendment shall modify and supersede all inconsistent terms and provisions set
forth in the Agreement and the

                                       3

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other Loan Documents and except as expressly modified and superseded by this
Amendment, the terms and provisions of the Agreement and the other Loan
Documents are ratified and confirmed and shall continue in full force and
effect. The Borrower, the Account Party and the Issuing Bank agree that the
Agreement as amended hereby shall continue to be legal, valid, binding and
enforceable in accordance with its terms.

      Section 4.2 Representations and Warranties. The Borrower and the Account
Party hereby represent and warrant to the Issuing Bank that (a) the execution,
delivery and performance of this Amendment and any and all other Loan Documents
executed or delivered in connection herewith have been authorized by all
requisite corporate action on the part of the Borrower and the Account Party and
will not violate the certificate of incorporation, bylaws or other
organizational documents of the Borrower and the Account Party, (b) the
representations and warranties contained in the Agreement, as amended hereby,
and any other Loan Document are true and correct on and as of the date hereof as
though made on and as of the date hereof except for those that relate solely to
a specific date or have changed as a result of transactions permitted by the
Agreement, (c) after giving effect to this Amendment, no Default or Event of
Default has occurred and is continuing, and (d) after giving effect to this
Amendment, the Borrower and the Account Party is in full compliance with all
covenants and agreements contained in the Agreement as amended hereby.

                                   ARTICLE V

                                 Miscellaneous

      Section 5.1 Survival of Representations and Warranties. All
representations and warranties made in this Amendment or any other Loan Document
including any Loan Document furnished in connection with this Amendment shall
survive the execution and delivery of this Amendment and the other Loan
Documents, and no investigation by the Issuing Bank shall affect the
representations and warranties or the right of the Issuing Bank to rely upon
them.

      Section 5.2 Severability. Any provision of this Amendment held by a court
of competent jurisdiction to be invalid or unenforceable shall not impair or
invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

      Section 5.3 APPLICABLE LAW. THIS AMENDMENT AND ALL OTHER LOAN DOCUMENTS
EXECUTED PURSUANT HERETO SHALL BE DEEMED TO HAVE BEEN MADE AND TO BE PERFORMABLE
IN TEXAS AND SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF
THE STATE OF TEXAS.

      Section 5.4 Successors and Assigns. This Amendment is binding upon and
shall inure to the benefit of the Issuing Bank, the Account Party and the
Borrower and their respective successors and assigns, except the Borrower and
the Account Party may not assign or transfer its rights or obligations hereunder
without the prior written consent of the Issuing Bank.

      Section 5.5 Counterparts. This Amendment may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original,
but all of which

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when taken together shall constitute one and the same instrument. Facsimiles of
signatures shall be binding and effective as originals.

      Section 5.6 Effect of Waiver. No consent or waiver, express or implied, by
the Issuing Bank to or for any breach of or deviation from any covenant,
condition or duty by the Borrower or the Account Party shall be deemed a consent
or waiver to or of any other breach of the same or any other covenant, condition
or duty.

      Section 5.7 Headings. The headings, captions, and arrangements used in
this Amendment are for convenience only and shall not affect the interpretation
of this Amendment.

      Section 5.8 ENTIRE AGREEMENT. THIS AMENDMENT, THE AGREEMENT AND THE OTHER
LOAN DOCUMENTS EMBODY THE FINAL, ENTIRE AGREEMENT BETWEEN THE PARTIES HERETO
RELATING TO THIS AMENDMENT AND SUPERSEDE ANY AND ALL PRIOR COMMITMENTS,
AGREEMENTS, REPRESENTATIONS AND UNDERSTANDINGS, WHETHER WRITTEN OR ORAL,
RELATING TO THIS AMENDMENT, AND MAY NOT BE CONTRADICTED OR VARIED BY EVIDENCE OF
PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS OR DISCUSSIONS OF THE
PARTIES HERETO. THERE ARE NO ORAL AGREEMENTS BETWEEN THE PARTIES HERETO.

[The Remainder of This Document Is Intentionally Left Blank. Signature Pages
Follow.]

                                       5

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      IN WITNESS WHEREOF, this Amendment is executed as of the date first set
forth above.

                              BORROWER:

                              WCA WASTE SYSTEMS, INC.

                              By: /s/ Charles A. Casalinova
                                  --------------------------------------
                                  Charles A. Casalinova
                                  Vice President

                              ACCOUNT PARTY:

                              WASTE CORPORATION OF TEXAS, L.P.

                              By: WCA Texas Management General, Inc.,
                                  as its general partner

                              By: /s/ Charles A. Casalinova
                                  --------------------------------------
                                  Charles A Casalinova
                                  Vice President

          Signature Page to First Amendment to Reimbursement Agreement

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                              ISSUING BANK:

                              WELLS FARGO BANK, NATIONAL ASSOCIATION

                              By: /s/ Michael Real
                                  --------------------------------------
                                  Michael Real
                                  Vice President

          Signature Page to First Amendment to Reimbursement Agreement