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                                                                    Exhibit 10.7

                              WCA WASTE CORPORATION
                            ONE RIVERWAY, SUITE 1400
                                HOUSTON, TX 77056

July 27, 2006

Ares Corporate Opportunities Fund II, L.P.
1999 Avenue of the Stars, Suite 1900
Los Angeles, CA  90067

Attn: Jeffrey Serota

Re:  Management Rights

Ladies and Gentlemen:

You have requested that WCA Waste Corporation, a Delaware corporation (the
"COMPANY"), grant certain contractual management rights to Ares Corporate
Opportunities Fund II, L.P. (the "INVESTOR") so that the purchase by the
Investor of shares of the Company's Series A Convertible Preferred Stock, par
value $0.01 per share (the "Stock"), pursuant to the Preferred Stock Purchase
Agreement, dated as of the date hereof among the Company, the Investor and the
other parties thereto, as such agreement may be amended, supplemented or
otherwise modified from time to time (the "PURCHASE AGREEMENT"), may qualify as
a "venture capital investment" as described in clause (d)(3)(i) of the U.S.
Department of Labor Regulations Section 2510.3-101 (the "DOL REGULATION").
Reference is made to the Stockholder's Agreement (the "STOCKHOLDER'S
AGREEMENT"), dated as of July 27, 2006 between the Company and the Investor,
executed in connection with the Purchase Agreement. Capitalized terms used
herein but not otherwise defined shall have the meanings provided in the
Stockholder's Agreement. This letter will confirm our agreement that the
Investor will be entitled to the contractual management rights enumerated below
("MANAGEMENT RIGHTS").

After the Stockholder Designee Period but during the Standstill Period, the
Company will provide one representative designated on behalf of the Stockholder
with the following access during normal business hours with reasonable prior
written notice and subject to reasonable limitations imposed by the Company
(including limitations relating to the frequency of access):

      (a)   access to such properties, books and records of the Company (and its
            subsidiaries) and information relating to the Company (and its
            subsidiaries), its properties, operations, finances and affairs
            ("INFORMATION") as the Stockholder through such representative may
            reasonably request;

      (b)   the right to consult with and advise the senior executive management
            of the Company (that is, the officers designated as executive
            officers in the Company's proxy statements) from time to time
            regarding the Company (including its subsidiaries), its properties,
            operations, finances and affairs;

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      (c)   The Company will consider, in good faith, the recommendations of the
            Stockholder in connection with the matters on which it is consulted
            as described above, recognizing that the ultimate discretion with
            respect to all such matters shall be retained by the Company; and

      (d)   If the Company is not a "reporting company" under Section 12 of the
            Securities Exchange Act of 1934, as amended, the Company shall
            deliver to the Stockholder:

            1.    as soon as available and in any event within 45 days after the
                  end of each of the first three quarters of each fiscal year of
                  the Company, consolidated balance sheets of the Company and
                  its subsidiaries as of the end of such period, and
                  consolidated statements of income and cash flows of the
                  Company, and its subsidiaries for the period then ended
                  prepared in conformity with generally accepted accounting
                  principles in the United States applied on a consistent basis,
                  except as otherwise noted therein, and subject to the absence
                  of footnotes and to year-end adjustment; and

            2.    as soon as available and in any event within 90 days after the
                  end of each fiscal year of the Company, a consolidated balance
                  sheet of the Company and its subsidiaries as of the end of
                  such year, and consolidated statements of income and cash
                  flows of the Company and its subsidiaries for the year then
                  ended prepared in conformity with generally accepted
                  accounting principles in the United States applied on a
                  consistent basis, except as otherwise noted therein, together
                  with an auditor's report thereon of a firm of established
                  national reputation.

The Stockholder has requested the Management Rights provided herein to enable
the Shares held by such Stockholder to qualify as a "venture capital investment"
as to which such Stockholder has "management rights," in each case as such terms
are defined in Department of Labor Regulation Section 2510.3-101(d); provided,
however, that nothing herein shall require the Company to furnish such
Stockholder with more than rights of access to Information and consultation
provided herein regardless of whether such rights are sufficient for such
Stockholder to comply with venture capital operating company requirements.

The Stockholder agrees to hold in strict confidence (and not to disclose) all
nonpublic Information furnished to it and to use all Information only in
connection with the management of their investment in the Company, not to take
any action that would require the Company to make a public disclosure of
Information that was previously nonpublic, and not to purchase or acquire any
securities or taking any trading or hedging position with respect thereto. Any
representative of Stockholder shall sign an agreement to the foregoing effect.
If the Stockholder is required by a court or administrative agency to disclose
any of the nonpublic Information, the Stockholder shall promptly notify the
Company of such requirement (solely to the extent permitted by applicable law,
regulation or rule) so that the Company may at its own expense oppose such
requirement or seek a protective order and request confidential treatment of
such Information. It is agreed that if the Stockholder is nonetheless compelled
by such court or agency to disclose the Information, the Stockholder may
disclose such portion of the Information which is legally

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required without liability hereunder. In any event, the Stockholder will not
oppose action by the Company to obtain a protective order or other reliable
assurance that confidential treatment will be accorded the Information.

The Management Rights described herein shall terminate and be of no further
force or effect once the Investor no longer holds any shares of capital stock of
the Company.

This letter may not be amended except by a written instrument signed by the
Stockholder and the Company.

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Very truly yours,

WCA WASTE CORPORATION

By: /s/ J. Edward Menger
    ---------------------------------------
    Name: J. Edward Menger
    Title: Vice President and General Counsel

ACKNOWLEDGED AND ACCEPTED:

ARES CORPORATE OPPORTUNITIES FUND II, L.P.

By: ACOF MANAGEMENT II, L.P.,
    as general partner of Ares Corporate Opportunities Fund II, L.P.

By: ACOF OPERATING MANAGER II, L.P.,
    as general partner of ACOF Management II, L.P.

By: ARES MANAGEMENT, INC.
    as general partner of ACOF Operating Manager II, L.P..

By: /s/ David Kaplan
    ---------------------------------------
    Name:  David Kaplan
    Title:  Senior Partner