AMENDED AND RESTATED PLEDGE AGREEMENT

AGREEMENT

NOW, THEREFORE, in consideration of the foregoing and other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged and confessed, each Pledgor hereby agrees with the Administrative Agent for the benefit of the Secured Parties as follows:

Section 1.  Definitions .  All capitalized terms not otherwise defined in this Pledge Agreement that are defined in the Credit Agreement shall have the meanings assigned to such terms by the Credit Agreement.  Any terms used in this Pledge Agreement that are defined in the Uniform Commercial Code in effect in the State of Texas from time to time (the “UCC”) and not otherwise defined herein or in the Credit Agreement, shall have the meanings assigned to those terms by the UCC.  All meanings to defined terms, unless otherwise indicated, are to be equally applicable to both the singular and plural forms of the terms defined.  Article, Section, Schedule, and Exhibit references are to Articles and Sections of and Schedules and Exhibits to this Pledge Agreement, unless otherwise specified.  All references to instruments, documents, contracts, and agreements are references to such instruments, documents, contracts, and agreements as the same may be amended, supplemented, and otherwise modified from time to time, unless otherwise specified.  The words “hereof”, “herein” and “hereunder” and words of similar import when used in this Pledge Agreement shall refer to this Pledge Agreement as a whole and not to any particular provision of this Pledge Agreement.  As used herein, the term “including” means “including, without limitation,”. Paragraph headings have been inserted in this Pledge Agreement as a matter of convenience for reference only and it is agreed that such paragraph headings are not a part of this Pledge Agreement and shall not be used in the interpretation of any provision of this Pledge Agreement.

Section 2.  Pledge .

2.01.                         Grant of Pledge .

(a)                                   Each Pledgor hereby pledges to the Administrative Agent, and grants to the Administrative Agent, for the benefit of the Secured Parties, a continuing security interest in, the Pledged Collateral, as defined in Section 2.02 below.  This Pledge Agreement shall secure (i) all Obligations (as defined in the Credit Agreement) now or hereafter existing; (ii) all other amounts now or hereafter owed by the Borrower, any Pledgor, or any of their respective Subsidiaries under this Pledge Agreement, the Credit Agreement or the other Loan Documents to the Administrative Agent or any other Secured Party; and (iii) any increases, extensions, modifications, substitutions, amendments, restatements and renewals of any of the foregoing obligations, whether for principal, interest, fees, expenses, indemnification or otherwise.  All such obligations shall be referred to in this Pledge Agreement as the “ Secured Obligations ”.

(b)                                  Notwithstanding anything contained herein to the contrary, it is the intention of each Pledgor, the Administrative Agent and the Secured Parties that the amount of the Secured Obligation secured by each Pledgor’s interests in any of its property or assets (whether real or personal, or mixed, tangible or intangible) (“ Property ”) shall be in, but not in excess of, the maximum amount permitted by fraudulent

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conveyance, fraudulent transfer and other similar law, rule or regulation of any Governmental Authority (as defined in the Credit Agreement) applicable to such Pledgor. Accordingly, notwithstanding anything to the contrary contained in this Pledge Agreement or in any other agreement or instrument executed in connection with the payment of any of the Secured Obligations, the amount of the Secured Obligations secured by each Pledgor’s interests in any of its Property pursuant to this Pledge Agreement shall be limited to an aggregate amount equal to the largest amount that would not render such Pledgor’s obligations hereunder or the liens and security interest granted to the Administrative Agent hereunder subject to avoidance under Section 548 of the United States Bankruptcy Code or any comparable provision of any other applicable law.

2.02.                         Pledged Collateral .  “ Pledged Collateral ” shall mean all of each Pledgor’s right, title, and interest in the following, whether now owned or hereafter acquired:

(a)                                   (i) all of the membership interests listed in the attached Schedule 2.02(a) issued to such Pledgor and all such additional membership interests of any issuer of such interests hereafter acquired by such Pledgor (the “ Membership Interests ”), (ii) the certificates representing the Membership Interests, if any, and (iii) all rights to money or Property which such Pledgor now has or hereafter acquires in respect of the Membership Interests,  including, without limitation, (A) any proceeds from a sale by or on behalf of such Pledgor of any of the Membership Interests, and (B) any distributions, dividends, cash, instruments and other property from time-to-time received or otherwise distributed in respect of the Membership Interests, whether regular, special or made in connection with the partial or total liquidation of the issuer and whether attributable to profits, the return of any contribution or investment or otherwise attributable to the Membership Interests or the ownership thereof  (collectively, the “ Membership Interests Distributions ”);

(b)                                  (i) all of the general and limited partnership interests listed in the attached Schedule 2.02(b) issued to such Pledgor and all such additional limited or general partnership interests of any issuer of such interests hereafter acquired by such Pledgor (the “ Partnership Interests ”), and (ii) all rights to money or Property which such Pledgor now has or hereafter acquires in respect of the Partnership Interests,  including, without limitation, (A) any proceeds from a sale by or on behalf of such Pledgor of any of the Partnership Interests, and (B) any distributions, dividends, cash, instruments and other property from time-to-time received or otherwise distributed in respect of the Partnership Interests, whether regular, special or made in connection with the partial or total liquidation of the issuer and whether attributable to profits, the return of any contribution or investment or otherwise attributable to the Partnership Interests or the ownership thereof  (collectively, the “ Partnership Interests Distributions ”);

(c)                                   (i) all of the shares of stock listed in the attached Schedule 2.02(c) issued to such Pledgor and all such additional shares of stock of any issuer of such shares of stock hereafter issued to such Pledgor (the “ Pledged Shares ”), (ii) the certificates representing the Pledged Shares, and (iii) all rights to money or Property which such Pledgor now has or hereafter acquires in respect of the Pledged Shares, including,

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without limitation, (A) any proceeds from a sale by or on behalf of such Pledgor of any of the Pledged Shares, and (B) any distributions, dividends, cash, instruments and other property from time-to-time received or otherwise distributed in respect of the Pledged Shares, whether regular, special or made in connection with the partial or total liquidation of the issuer and whether attributable to profits, the return of any contribution or investment or otherwise attributable to the Pledged Shares or the ownership thereof (collectively, the “ Pledged Shares Distributions ”; together with the Membership Interests Distributions and the Partnership Interest Distributions, the “ Distributions ”); and

(d)                                  all proceeds from the Pledged Collateral described in paragraphs (a), (b) and (c) of this Section 2.02.

2.03.                         Delivery of Pledged Collateral .  All certificates or instruments, if any, representing the Pledged Collateral shall be delivered to the Administrative Agent and shall be in suitable form for transfer by delivery, or shall be accompanied by duly executed instruments of transfer or assignment in blank, all in form and substance reasonably satisfactory to the Administrative Agent.  After the occurrence and during the continuance of an Event of Default, the Administrative Agent shall have the right, upon prior written notice to the applicable Pledgor, to transfer to or to register in the name of the Administrative Agent or any of its nominees any of the Pledged Collateral, subject to the rights specified in Section 2.04.  In addition, after the occurrence and during the continuance of an Event of Default, the Administrative Agent shall have the right at any time to exchange the certificates or instruments representing the Pledged Collateral for certificates or instruments of smaller or larger denominations.

2.04.                         Rights Retained by Pledgor .  Notwithstanding the pledge in Section 2.01,

(a)                                   so long as no Event of Default shall have occurred and remain uncured or unwaived and except as otherwise provided in the Credit Agreement, (i) each Pledgor shall be entitled to receive and retain any dividends and other Distributions paid on or in respect of the Pledged Collateral and the proceeds of any sale of the Pledged Collateral; and (ii) each Pledgor shall be entitled to exercise any voting and other consensual rights pertaining to its Pledged Collateral for any purpose not inconsistent with the terms of this Pledge Agreement or the Credit Agreement; provided , however , that no Pledgor shall exercise nor shall it refrain from exercising any such right if such action or inaction, as applicable, would have a materially adverse effect on the value of the Pledged Collateral; and

(b)                                  if an Event of Default shall have occurred and remain uncured or unwaived,

(i)                                      until such time thereafter as the Administrative Agent gives written notice of its election to exercise such voting and other consensual rights pursuant to Section 5.02 hereof, each Pledgor shall be entitled to exercise any voting and other consensual rights pertaining to its Pledged Collateral for any purpose not inconsistent with the terms of this Pledge Agreement or the Credit Agreement; provided , however , that no Pledgor shall exercise nor shall it refrain from

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exercising any such right if such action or inaction, as applicable, would have a materially adverse effect on the value of the Pledged Collateral; and

(ii)                                   at and after such time as the Administrative Agent gives written notice of its election to exercise such voting and other consensual rights pursuant to Section 5.02 hereof, each Pledgor shall execute and deliver (or cause to be executed and delivered) to the Administrative Agent all proxies and other instruments as the Administrative Agent may reasonably request to enable the Administrative Agent to (A) exercise the voting and other rights which such Pledgor is entitled to exercise pursuant to paragraph (a) or paragraph (b)(i) of this Section 2.04, and (B) receive any Distributions and proceeds of sale of the Pledged Collateral which such Pledgor is authorized to receive and retain pursuant to paragraph (a)(i) of this Section 2.04.

Section 3.  Pledgor’s Representations and Warranties .  Each Pledgor represents and warrants to the Administrative Agent and the Secured Parties as follows:

(a)                                   The Pledged Collateral applicable to such Pledgor listed on the attached Schedules 2.02(a), 2.02(b) and 2.02(c) have been duly authorized and validly issued to such Pledgor and are fully paid and nonassessable.

(b)                                  Such Pledgor is the legal and beneficial owner of the Pledged Collateral free and clear of any Lien or option, except for (i) the security interest created by this Pledge Agreement and (ii) other Liens permitted under the Credit Agreement ( the “ Permitted Liens ”).

(c)                                   No authorization, authentication, approval, or other action by, and no notice to or filing with, any Governmental Authority or regulatory body is required either (a) for the pledge by such Pledgor of the Pledged Collateral pursuant to this Pledge Agreement or for the execution, delivery, or performance of this Pledge Agreement by such Pledgor or (b) for the exercise by the Administrative Agent or any Secured Party of the voting or other rights provided for in this Pledge Agreement or the remedies in respect of the Pledged Collateral pursuant to this Pledge Agreement (except as may be required in connection with such disposition by laws affecting the offering and sale of securities generally).

(d)                                  Such Pledgor has the full right, power and authority to deliver, pledge, assign and transfer the Pledged Collateral to the Administrative Agent.

(e)                                   The Membership Interests listed on the attached Schedule 2.02(a) constitute the percentage of the issued and outstanding membership interests of the respective issuer thereof set forth on Schedule 2.02(a) and all of the Equity Interest in such issuer in which the Pledgor has any ownership interest.

(f)                                     The Partnership Interests listed on the attached Schedule 2.02(b) constitute the percentage of the issued and outstanding general and limited partnership interests of the respective issuer thereof set forth on Schedule 2.02(b) and all of the Equity Interest in such issuer in which the Pledgor has any ownership interest.

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(g)                                  The Pledged Shares list on the attached Schedule 2.02(c) constitute the percentage of the issued and outstanding shares of capital stock of the respective issuer thereof set forth on Schedule 2.02(c) and all of the Equity Interest in such issuer in which the Pledgor has any ownership interest.

(h)                                  Schedule 3 sets forth its sole jurisdiction of formation, type of organization, federal tax identification number, the organizational number, and all names used by it during the last five years prior to the date of this Pledge Agreement.

Section 4.  Pledgor’s Covenants .  During the term of this Pledge Agreement and until all of the Secured Obligations (including all Letter of Credit Obligations) have been fully and finally paid and discharged in full, the termination of the Hedge Contracts with the Secured Parties, the Commitments (as defined in the Credit Agreement) under the Credit Agreement have been terminated or expired, all Letters of Credit have terminated or expired, and all obligations of the Issuing Lender and the Lenders in respect of Letters of Credit have been terminated, each Pledgor covenants and agrees with the Administrative Agent that:

4.01.                         Protect Collateral; Further Assurances .  Each Pledgor will warrant and defend the rights and title herein granted unto the Administrative Agent in and to the Pledged Collateral (and all right, title, and interest represented by the Pledged Collateral) against the claims and demands of all Persons whomsoever.  Each Pledgor agrees that, at the expense of such Pledgor, such Pledgor will promptly execute and deliver all further instruments and documents, and take all further action, that may be reasonably necessary and that the Administrative Agent or any Secured Party may reasonably request, in order to perfect and protect any security interest granted or purported to be granted hereby or to enable the Administrative Agent or any Secured Party to exercise and enforce its rights and remedies hereunder with respect to any Pledged Collateral.  Each Pledgor hereby authorizes the Administrative Agent to file any financing statements, amendments or continuations without the signature of such Pledgor to the extent permitted by applicable law in order to perfect or maintain the perfection of any security interest granted under this Pledge Agreement.

4.02.                         Transfer, Other Liens, and Additional Shares .  Each Pledgor agrees that it will not (a) except as otherwise permitted by the Credit Agreement, sell or otherwise dispose of, or grant any option with respect to, any of the Pledged Collateral or (b) create or permit to exist any Lien upon or with respect to any of the Pledged Collateral, except for Permitted Liens.  Each Pledgor agrees that it will (i) cause each issuer of the Pledged Collateral that is a Subsidiary of such Pledgor not to issue any other Equity Interests in addition to or in substitution for the Pledged Collateral issued by such issuer, except to such Pledgor or any other Pledgor and (ii) pledge hereunder, immediately upon its acquisition (directly or indirectly) thereof, any additional Equity Interests of an issuer acquired by such Pledgor.  No Pledgor shall approve any amendment or modification of any of the Pledged Collateral without the Administrative Agent’s prior written consent.

4.03.                         Jurisdiction of Formation; Name Change.   Each Pledgor shall give the Administrative Agent at least 30 days’ prior written notice before it (i) in the case of a Pledgor that is not a “registered organization” (as defined in Section 9-102 of the UCC) changes the location of its principal place of business and chief executive office, or (ii) uses a trade name

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other than its current name used on the date hereof.  Other than as permitted by Section 6.11 of the Credit Agreement, no Pledgor shall amend, supplement, modify or restate its articles or certificate of incorporation, bylaws, limited liability company agreements, or other equivalent organizational documents, nor amend its name or change its jurisdiction of incorporation, organization or formation.

Section 5.  Remedies upon Default .  If any Event of Default shall have occurred and be continuing:

5.01.                         UCC Remedies .  To the extent permitted by law, the Administrative Agent may exercise in respect of the Pledged Collateral, in addition to other rights and remedies provided for in this Pledge Agreement or otherwise available to it, all the rights and remedies of a Administrative Agent under the UCC (whether or not the UCC applies to the affected Pledged Collateral).

5.02.                         Dividends and Other Rights .

(a)                                   All rights of the Pledgors to exercise the voting and other consensual rights which it would otherwise be entitled to exercise pursuant to Section 2.04(a) may be exercised by the Administrative Agent if the Administrative Agent so elects and gives written notice of such election to the affected Pledgor and all rights of the Pledgors to receive any Distributions on or in respect of the Pledged