Exhibit 10.1

Summary of Initial Compensation Terms

For John R. Bakht

Exhibit 10.2

Execution Version

AGREEMENT AND AMENDMENT NO. 4

This AGREEMENT AND AMENDMENT NO. 4 (the “ Agreement ”) dated as of July 27, 2015 (the “ Effective Date ”) is among CARBO Ceramics Inc., a Delaware corporation (the “ Borrower ”), the Lenders (as defined below) and Wells Fargo Bank, National Association, as administrative agent (in such capacity, the “ Administrative Agent ”), as swing line lender (the “ Swing Line Lender ”), and as issuing lender (in such capacity, the “ Issuing Lender ”) for such Lenders.

RECITALS

A. The Borrower is party to that certain Credit Agreement dated as of January 29, 2010, among the Borrower, the lenders party thereto from time to time (the “ Lenders ”), the Administrative Agent, the Swing Line Lender, and the Issuing Lender (as may be amended, restated or otherwise modified from time to time, the “ Credit Agreement ”).

B. The Borrower has requested that the Lenders, the Administrative Agent, the Swing Line Lender, and the Issuing Lender make certain amendments to the Credit Agreement, as provided herein and subject to the terms and conditions set forth herein.

THEREFORE, the Borrower, the Lenders, the Administrative Agent, the Swing Line Lender, and the Issuing Lender hereby agree as follows:

Section 1. Defined Terms . As used in this Agreement, each of the terms defined in the opening paragraph and the Recitals above shall have the meanings assigned to such terms therein. Each term defined in the Credit Agreement and used herein without definition shall have the meaning assigned to such term in the Credit Agreement, unless expressly provided to the contrary.

Section 2. Other Definitional Provisions . Article, Section, Schedule, and Exhibit references are to Articles and Sections of and Schedules and Exhibits to this 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 Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement. The term “including” means “including, without limitation.” Paragraph headings have been inserted in this Agreement as a matter of convenience for reference only and it is agreed that such paragraph headings are not a part of this Agreement and shall not be used in the interpretation of any provision of this Agreement.

Section 3. Amendments to Credit Agreement .

Section 4. Decrease in Commitments . The parties hereby agree and acknowledge that (a) the aggregate Revolving Commitments shall be reduced to $90,000,000.00 and (b) the Lenders’ respective Revolving Commitments shall be the amount set forth next to the respective names under the caption “Revolving Commitment” on Schedule II attached hereto.

Section 5. Borrower Representations and Warranties . The Borrower represents and warrants that: (a) the representations and warranties contained in the Credit Agreement, as amended hereby, and the representations and warranties contained in the other Credit Documents, are true and correct in all material respects on and as of the Effective Date as if made on as and as of such date except to the extent that any such representation or warranty expressly relates solely to an earlier date, in which case such representation or warranty is true and correct in all material respects as of such earlier date; (b) no Default has occurred and is continuing; (c) the execution, delivery and performance of this Agreement are within the corporate power and authority of the Borrower and have been duly authorized by appropriate corporate and governing action and proceedings; (d) this Agreement constitutes the legal, valid, and binding obligation of the Borrower enforceable in accordance with its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, or similar laws affecting the rights of creditors generally and general principles of equity; (e) as of the Effective Date, (i) there are no Material Domestic Subsidiaries and (ii) no Non-Material Domestic Subsidiary is required to be a Guarantor pursuant to Section 5.6 of the Credit Agreement and (f) there are no governmental or other third party consents, licenses and approvals required in connection with the execution, delivery, performance, validity and enforceability of this Agreement.

Section 6. Conditions to Effectiveness . This Agreement shall become effective on the Effective Date and enforceable against the parties hereto upon the occurrence of the following conditions precedent:

(a) The Administrative Agent shall have received multiple original counterparts, as requested by the Administrative Agent, of:

(1) This Agreement duly and validly executed and delivered by duly authorized officers of the Borrower, the Administrative Agent, the Swing Line Lender, the Issuing Lender, and the Lenders;

(2) the Security Agreement executed by each Credit Party existing on the Effective Date, together with appropriate UCC-1 financing statements, if any, necessary or desirable for filing with the appropriate authorities and any other documents, agreements, or instruments necessary to create, perfect or maintain an Acceptable Security Interest in the Collateral described in the Security Agreement; and

(3) a secretary’s certificate from the Borrower certifying the Borrower’s officers’ incumbency, authorizing resolutions and organizational documents.

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(b) No Default shall have occurred and be continuing as of the Effective Date.

(c) The representations and warranties in this Agreement shall be true and correct.

(d) The Borrower shall have paid (i) the amendment fee as set forth in Section 7(f) below and (ii) all other costs and expenses which have been invoiced and are payable pursuant to Section 10.1 of the Credit Agreement.

(e) The Borrower shall have prepaid the Advances pursuant to Section 2.5(b) of the Credit Agreement, such that, after giving effect to such prepayment, the Outstandings (as defined in Annex A) do not exceed $90,000,000.00.

Section 7. Acknowledgments and Agreements .

(a) The Borrower acknowledges that on the date hereof all Secured Obligations (as defined in Annex A) are payable without defense, offset, counterclaim or recoupment.

(b) The Administrative Agent and the Lenders hereby expressly reserve all of their rights, remedies, and claims under the Credit Documents. Nothing in this Agreement shall constitute a waiver or relinquishment of (i) any Default or Event of Default under any of the Credit Documents (other than the Subject Waivers as expressly provided herein), (ii) any of the agreements, terms or conditions contained in any of the Credit Documents, (iii) any rights or remedies of the Administrative Agent or any Lender with respect to the Credit Documents or (iv) the rights of the Administrative Agent or any Lender to collect the full amounts owing to them under the Credit Documents.

(c) Each of the Borrower, the Administrative Agent, the Swing Line Lender, the Issuing Lender and the Lenders does hereby adopt, ratify, and confirm the Credit Agreement, as amended hereby, and acknowledges and agrees that the Credit Agreement, as amended hereby, is and remains in full force and effect, and the Borrower acknowledges and agrees that its liabilities and obligations under the Credit Agreement, as amended hereby, are not impaired in any respect by this Agreement.

(d) From and after the Effective Date, all references to the Credit Agreement and the Credit Documents shall mean such Credit Agreement and such Credit Documents as amended by this Agreement.

(e) This Agreement is a Credit Document for the purposes of the provisions of the other Credit Documents. Without limiting the foregoing, any breach of representations, warranties, and covenants under this Agreement shall be a Default or Event of Default, as applicable, under the Credit Agreement.

(f) In consideration of the agreements of the Lenders set forth in this Agreement, the Borrower agrees to pay to the Administrative Agent, for the account of each Lender, an amendment fee in an amount equal to 0.15% of such Lender’s Commitment (after giving effect to the prepayment of Advances required under Section 6(e) above). Each such amendment fee as to such Lender (i) is payable in U.S. dollars in immediately available funds, free and clear of, and without deduction for, any and all present or future applicable taxes, levies, imposts, deductions, charges or withholdings and all liabilities with respect thereto (with appropriate gross-up for withholding taxes), (ii) is not refundable under any circumstances, (iii) will not be subject to counterclaim, defense, setoff or otherwise affected, and (iv) is deemed fully earned by such Lender once its signature page is delivered as provided above and the Effective Date has occurred.

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Section 8. Counterparts . This Agreement may be signed in any number of counterparts, each of which shall be an original and all of which, taken together, constitute a single instrument. This Agreement may be executed by facsimile signature and all such signatures shall be effective as originals.

Section 9. Successors and Assigns . This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns permitted pursuant to the Credit Agreement.

Section 10. Invalidity . In the event that any one or more of the provisions contained in this Agreement shall for any reason be held invalid, illegal or unenforceable in any respect, such invalidity, illegality or unenforceability shall not affect any other provision of this Agreement.

Section 11. Governing Law . This Agreement shall be deemed to be a contract made under and shall be governed by and construed in accordance with the laws of the State of Texas.

Section 12. USA PATRIOT Act . Each Lender that is subject to the PATRIOT Act and the Administrative Agent (for itself and not on behalf of any Lender) hereby notifies each Credit Party that pursuant to the requirements of the PATRIOT Act it is required to obtain, verify and record information that identifies such Credit Party, which information includes the name and address of such Credit Party and other information that will allow such Lender or the Administrative Agent, as applicable, to identify such Credit Party in accordance with the PATRIOT Act.

Section 13. Entire Agreement . THIS AGREEMENT, THE CREDIT AGREEMENT AS AMENDED BY THIS AGREEMENT, THE NOTES, AND THE OTHER CREDIT DOCUMENTS CONSTITUTE THE ENTIRE UNDERSTANDING AMONG THE PARTIES HERETO WITH RESPECT TO THE SUBJECT MATTER HEREOF AND SUPERSEDE ANY PRIOR AGREEMENTS, WRITTEN OR ORAL, WITH RESPECT THERETO.

THERE ARE NO UNWRITTEN ORAL AGREEMENTS AMONG THE PARTIES.

[ signature pages follow ]

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EXECUTED effective as of the date first above written.

Signature Page to Agreement and Amendment No. 4

ANNEX A TO AGREEMENT AND AMENDMENT NO. 4 TO CREDIT AGREEMENT

CREDIT AGREEMENT

dated as of January 29, 2010

Among

CARBO CERAMICS INC.

as Borrower,

WELLS FARGO BANK, NATIONAL ASSOCIATION

as Administrative Agent, Issuing Lender and Swing Line Lender,

and

THE LENDERS NAMED HEREIN

as Lenders

$90,000,000

WELLS FARGO BANK, NATIONAL ASSOCIATION

As Sole Lead Arranger

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CREDIT AGREEMENT

This CREDIT AGREEMENT dated as of January 29, 2010 (the “Agreement”) is among (a) CARBO Ceramics Inc., a Delaware corporation (the “Borrower”), (b) the Lenders (as defined below), and (c) Wells Fargo Bank, National Association as Swing Line Lender (as defined below), Issuing Lender (as defined below), and as Administrative Agent (as defined below) for the Lenders.

In consideration of the mutual covenants and agreements herein contained, the parties hereto hereby agree as follows:

ARTICLE 1

DEFINITIONS AND ACCOUNTING TERMS

Section 1.1 Certain Defined Terms . The following terms shall have the following meanings (unless otherwise indicated, such meanings to be equally applicable to both the singular and plural forms of the terms defined):

“ Acceptable Security Interest ” means a security interest which (a) exists in favor of the Administrative Agent for its benefit and the ratable benefit of the Issuing Lender, the Swingline Lender and the Lenders, (b) is superior to all other security interests (other than the Permitted Liens), (c) secures the Obligations, and (d) is perfected and enforceable against the Credit Party which created such security interest.

“ Account Debtor ” shall mean an account debtor as defined in the Uniform Commercial Code, as in effect in the State of Texas.

“ Acquisition ” means the purchase by any Credit Party of any business, including the purchase of associated assets or operations or the Equity Interests of a Person.

“ Adjusted Base Rate ” means, for any day, the fluctuating rate per annum of interest equal to the greatest of (a) the Prime Rate in effect on such day, (b) the Federal Funds Rate in effect on such day plus 1.50%, and (c) a rate determined by the Administrative Agent to be the Daily One-Month LIBOR plus 1.50%. Any change in the Adjusted Base Rate due to a change in the Prime Rate, Daily One-Month LIBOR or the Federal Funds Rate shall be effective on the effective date of such change in the Prime Rate, Daily One-Month LIBOR or the Federal Funds Rate.

“ Administrative Agent ” means Wells Fargo in its capacity as agent for the Lenders pursuant to Article 8 and any successor agent pursuant to Section 8.7.

“ Administrative Questionnaire ” means an Administrative Questionnaire in a form supplied by the Administrative Agent.

“ Advance ” means any advance by a Lender or the Swing Line Lender to the Borrower as a part of a Borrowing.

“ Affiliate ” means, as to any Person, any other Person that, directly or indirectly, through one or more intermediaries, controls, is controlled by, or is under common control with, such Person or any Subsidiary of such Person. The term “control” (including the terms “controlled by” or “under common control with”) means the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a Person, whether through ownership, by contract, or otherwise.

“ Agreement ” is defined in the introductory paragraph hereof.

“ Alternative Covenant Period ” means the period commencing on July 1, 2015 and ending on the Business Day immediately following the date on which the financial statements and reports required under Section 5.2(b) and corresponding Compliance Certificate for the fiscal quarter ending March 31, 2017 is delivered by the Borrower to the Administrative Agent.

“ Amendment No. 2 Effective Date ” means July 25, 2013

“ Amendment No. 3 Effective Date ” means October 31, 2014.

“ Amendment No. 4 Effective Date ” means July 27, 2015.

“ Anti-Corruption Laws ” means all laws, rules, and regulations of any jurisdiction applicable to the Borrower or any of its Subsidiaries from time to time concerning or relating to bribery or corruption.

“ Applicable Margin ” means, at any time with respect to each Type of Advance, the Letters of Credit and the Commitment Fee, the percentage rate per annum which is applicable at such time with respect to such Advance, Letter of Credit or Commitment Fee as set forth in Schedule I and subject to further adjustments as set forth in Section 2.8(c).

“ Approved Fund ” means any Fund that is administered or managed by (a) a Lender, (b) an Affiliate of a Lender or (c) an entity or an Affiliate of an entity that administers or manages a Lender.

“ Asset Coverage Ratio ” means, as of any date of determination, the ratio of (a) Net Total Assets to (b) outstanding consolidated Debt of the Borrower on such date.

“ Asset Coverage Ratio Certificate ” means a certificate executed by a Responsible Officer of the Borrower or such other Person as required by this Agreement in substantially the same form as Exhibit G .

“ Asset Sale ” means (a) any sale, transfer, or other disposition of any Property by any Credit Party and (b) any issuance or sale of any Equity Interests of any Subsidiary of the Borrower, in each case, to any Person other than a Credit Party; provided that, any sale, transfer or other disposition of Property from one Credit Party to another Credit Party as permitted under Section 6.8(a) and the sale of inventory in the ordinary course as permitted under Section 6.8(b) shall not constitute an “Asset Sale” for purposes of this Agreement.

“ Assignment and Acceptance ” means an assignment and acceptance executed by a Lender and an Eligible Assignee and accepted by the Administrative Agent, in substantially the same form as Exhibit A .

“ AutoBorrow Agreement ” means any agreement providing for automatic borrowing services between the Borrower and the Swing Line Lender.

“ Availability ” means, as of a date of determination, an amount equal to (a) the aggregate Revolving Commitments in effect at such time minus (b) the Outstandings at such time.

“ Banking Services ” means each and any of the following bank services provided to any Credit Party by any Banking Services Provider: (a) commercial credit cards, (b) stored value cards and (c) any

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other Treasury Management Arrangement (including, without limitation, controlled disbursement, purchase card arrangements, automated clearinghouse transactions, return items, overdrafts and interstate depository network services).

“ Banking Services Obligations ” means any and all obligations of the Borrower or any other Credit Party, whether absolute or contingent and howsoever and whensoever created, arising, evidenced or acquired (including all renewals, extensions and modifications thereof and substitutions therefor) in connection with Banking Services.

“ Banking Services Provider ” means any Lender or Affiliate of a Lender that provides Banking Services to the Borrower or any Credit Party.

“ Base Rate Advance ” means an Advance which bears interest based upon the Adjusted Base Rate.

“ Borrower ” means CARBO Ceramics Inc., a Delaware corporation.

“ Borrowing ” means a Revolving Borrowing or a Swing Line Borrowing.

“ Bilateral Obligations ” means all principal, interest (including post-petition interest), fees, reimbursements, indemnifications, and other amounts now or hereafter owed by any of the Credit Parties to Wells Fargo Bank, National Association (other than the Obligations) under any letter of credit agreement, indenture, loan or credit agreement or any other agreement evidencing or related to Debt (including letters of credit), and any increases, extensions, and rearrangements of those obligations under any amendments, supplements, and other modifications of the documents and agreements creating those obligations, and whether absolute or contingent and howsoever and whensoever created, arising, evidenced or acquired.

“ Business Day ” means a day (a) other than a Saturday, Sunday, or other day on which the Administrative Agent is authorized to close under the laws of, or is in fact closed in, Houston, Texas, and (b) if the applicable Business Day relates to any LIBOR Advances, on which dealings are carried on by commercial banks in the London interbank market.

“ Capital Expenditures ” for any Person and period of its determination means, without duplication, the aggregate of all expenditures and costs (whether paid in cash or accrued as liabilities during that period and including that portion of payments under Capital Leases that are capitalized on the balance sheet of such Person) of such Person during such period that, in conformity with GAAP, are required to be included in or reflected by the property, plant, or equipment or similar fixed asset accounts reflected in the balance sheet of such Person.

“ Capital Leases ” means, for any Person, any lease of any Property by such Person as lessee which would, in accordance with GAAP, be required to be classified and accounted for as a capital lease on the balance sheet of such Person.

“ Cash Collateral Account ” means a special cash collateral account pledged to the Administrative Agent, for its benefit and the ratable benefit of the Issuing Lender, the Swing Line Lender and the Lenders, containing cash deposited pursuant to the terms hereof to be maintained with Wells Fargo, as depository, in accordance with Section 2.2(h).

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“ CERCLA ” means the Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as amended, state and local analogs, and all rules and regulations and requirements thereunder in each case as now or hereafter in effect.

“ Change in Control ” means the occurrence of any of the following events:

(a) the Borrower ceases to own, either directly or indirectly, 100% of the Equity Interest in any Guarantor other than as a result of transaction permitted under Section 6.7 or Section 6.8;

(b) any “person” or “group” (as such terms are used in Sections 13(d) and 14(d) of the Exchange Act, but excluding any employee benefit plan of such person or its subsidiaries, any person or entity acting in its capacity as trustee, agent or other fiduciary or administrator of any such plan), becomes a “beneficial owner” (as defined in Rules 13d-3 and 13d-5 under the Exchange Act, except that a person or group shall be deemed to have “beneficial ownership” of all securities that such person or group has the right to acquire (such right, an “option right”), whether such right is exercisable immediately or only after the passage of time), directly or indirectly, of 50% or more of the Equity Interests of the Borrower entitled to vote for members of the board of directors or equivalent governing body of the Borrower on a fully-diluted basis (and taking into account all such securities that such person or group has the right to acquire pursuant to any option right); and

(c) during any period of 12 consecutive months, a majority of the members of the board of directors or other equivalent governing body of the Borrower cease to be composed of individuals (i) who were members of that board or equivalent governing body on the first day of such period, (ii) whose election or nomination to that board or equivalent governing body was approved by individuals referred to in clause (i) above constituting at the time of such election or nomination at least a majority of that board or equivalent governing body or (iii) whose election or nomination to that board or other equivalent governing body was approved by individuals referred to in clauses (i) and (ii) above constituting at the time of such election or nomination at least a majority of that board or equivalent governing body.

“ Change in Law ” means the occurrence, after the date of this Agreement, of any of the following: (a) the adoption or taking effect of any law, rule, regulation or treaty, (b) any change in any law, rule, regulation or treaty or in the administration, interpretation or application thereof by any Governmental Authority or (c) the making or issuance of any request, guideline or directive (whether or not having the force of law) by any Governmental Authority.

“ Class ” has the meaning set forth in Section 1.4.

“ Code ” means the Internal Revenue Code of 1986, as amended, and the regulations and published interpretations thereof.

“ Collateral ” means all property of the Credit Parties which is “Collateral” (as defined in the Security Agreement).

“ Commitment Fee ” means the fees set forth on Schedule I, which are payable in accordance with Section 2.7(a).

“ Commitments ” means, as to any Lender, its Revolving Commitment.

“ Compliance Certificate ” means a compliance certificate executed by a Responsible Officer of the Borrower or such other Person as required by this Agreement in substantially the same form as Exhibit B .

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“ Controlled Group ” means all members of a controlled group of corporations and all businesses (whether or not incorporated) under common control which, together with the Borrower or any Subsidiary, are treated as a single employer under Section 414 of the Code.

“ Convert ,” “ Conversion ,” and “ Converted ” each refers to a conversion of Advances of one Type into Advances of another Type pursuant to Section 2.4(b).

“ Credit Documents ” means this Agreement, the Notes, the Letters of Credit, the Letter of Credit Applications, the Guaranties, the Security Documents, the Notices of Borrowing, the Notices of Conversion, any Autoborrow Agreement, the Fee Letter, and each other agreement, instrument, or document executed at any time in connection with this Agreement.

“ Credit Parties ” means the Borrower and the Guarantors.

“ Daily One-Month LIBOR ” means, for any day, the rate of interest equal to the LIBO Rate then in effect for delivery for a one (1) month period.

“ Debt ” means, for any Person, without duplication: (a) indebtedness of such Person for borrowed money, including the face amount of any letters of credit supporting the repayment of indebtedness for borrowed money issued for the account of such Person; (b) to the extent not covered under clause (a) above, obligations under letters of credit and agreements relating to the issuance of letters of credit or acceptance financing, including Letters of Credit; (c) obligations of such Person evidenced by bonds, debentures, notes or other similar instruments, or upon which interest payments are customarily made; (d) obligations of such Person under conditional sale or other title retention agreements relating to any Properties purchased by such Person (other than customary reservations or retentions of title under agreements with suppliers entered into in the ordinary course of business); (e) obligations of such Person to pay the deferred purchase price of property, services, or Acquisitions (including, without limitation, any earn-out obligations, contingent obligations, or other similar obligations associated with such purchase, and including obligations that are non-recourse to the credit of such Person but are secured by the assets of such Person); (f) obligations of such Person as lessee under Capital Leases and obligations of such Person in respect of synthetic leases (except that the Jenkins Capital Lease Obligations and the Wilkinson Capital Lease Obligations shall not constitute Debt for purposes of the calculations for compliance under Sections 6.16 and 6.17); (g) obligations of such Person under any Hedging Arrangement (except that such obligations shall not constitute Debt for purposes of the calculations for compliance under Sections 6.16 and 6.17); (h) obligations of such Person owing in respect of redeemable preferred stock or other preferred Equity Interest of such Person; (i) the Debt of any partnership or unincorporated joint venture in which such Person is a general partner or a joint venturer, but only to the extent to which there is recourse to such Person for the payment of such Debt; (j) obligations of such Person under direct or indirect guaranties in respect of, and obligations (contingent or otherwise) of such Person to purchase or otherwise acquire, or otherwise to assure a creditor against loss in respect of, indebtedness or obligations of others of the kinds referred to in clauses (a) through (i) above; (k) indebtedness or obligations of others of the kinds referred to in clauses (a) through (j) secured by any Lien on or in respect of any Property of such Person, and (l) all liabilities of such Person in respect of unfunded vested benefits under any Plan.

“ Debtor Relief Laws ” means (a) the Bankruptcy Code of the United States of America, and (b) all other liquidation, conservatorship, bankruptcy, assignment for the benefit of creditors, moratorium, rearrangement, receivership, insolvency, reorganization, or similar debtor relief laws of the United States or other applicable jurisdictions from time to time in effect.

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“ Default ” means (a) an Event of Default or (b) any event or condition which with notice or lapse of time or both would, unless cured or waived, become an Event of Default.

“ Defaulting Lender ” means any Lender (a) that has failed to fund any portion of the Advances or participations in Letter of Credit Obligations or Swing Line Advances required to be funded by it hereunder within one Business Day of the date required to be funded by it hereunder unless, with the consent of the Administrative Agent and the Borrower (which consent may be withheld at the sole discretion of the Administrative Agent and the Borrower), such failure has been cured, (b) that has indicated to the Administrative Agent that such Lender will not fund any portion of the Advances or participations in Letter of Credit Obligations or Swing Line Advances required to be funded by it hereunder, unless, with the consent of the Administrative Agent and the Borrower (which consent may be withheld at the sole discretion of the Administrative Agent and the Borrower), such Lender actually funds such Advances or participations, (c) that has otherwise failed to pay over to the Administrative Agent or any other Lender any other amount required to be paid by it hereunder within one Business Day of the date when due, unless the subject of a good faith dispute, or unless, with the consent of the Administrative Agent (which consent may be withheld at the sole discretion of the Administrative Agent), such failure has been cured, (d) that the Administrative Agent believes, in good faith, has become a “defaulting lender” under any other credit facility to which such Lender is a party and has received notice of such belief from the Administrative Agent unless, with the consent of the Administrative Agent (which consent may be withheld at the sole discretion of the Administrative Agent), the consequences resulting in such “defaulting lender” status is no longer in effect, or (e) as to which a Lender Insolvency Event has occurred and is continuing with respect to such Lender. Any determination that a Lender is a Defaulting Lender will be made by the Administrative Agent in its sole discretion acting in good faith.

“ Dollars ” and “ $ ” means lawful money of the United States of America.

“ Domestic Subsidiary ” means any Subsidiary other than a Foreign Subsidiary.

“ EBITDA ” means, without duplication, for the Borrower and its Subsidiaries as a consolidated basis, and for any period, the sum of (a) the Borrower’s consolidated Net Income for such period plus (b) to the extent deducted in determining Borrower’s consolidated Net Income, Interest Expense, income taxes, depreciation, amortization and such other add-backs reasonably acceptable to the Administrative Agent; provided that such EBITDA shall be subject to pro forma adjustments for Acquisitions and Nonordinary Course Asset Sales assuming that such transactions had occurred on the first day of the determination period, which adjustments shall be made in accordance with the guidelines for pro forma presentations set forth by the SEC or in a manner otherwise reasonably acceptable to the Administrative Agent.

“ Effective Date ” means the date of this Agreement.

“ Eligible Assignee ” means (a) a Lender, (b) any Affiliate of a Lender approved by the Administrative Agent, (c) any Approved Fund approved by the Administrative Agent, or (d) any other Person (other than a natural Person) approved by the Administrative Agent and, unless an Event of Default has occurred and is continuing at the time any assignment is effected in accordance with Section 9.7, the Borrower, such approval not to be unreasonably withheld or delayed by the Borrower; provided , however, that (i) any financial institution employing any member of the board of directors (or comparable board) of any Credit Party shall not qualify as an Eligible Assignee, (ii) neither the Borrower nor any Affiliate of the Borrower shall qualify as an Eligible Assignee, and (iii) approval by the Administrative Agent of an Eligible Assignee shall not be unreasonably withheld, provided however, any disapproval by the Administrative Agent of a Person that fails to meet any of the following criteria shall not be considered unreasonable: (A) any commercial bank, savings and loan association or savings bank

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organized under the laws of the United States of America, or any state thereof, or any other Person, that has a combined capital and surplus of less than $100,000,000, (B) any commercial bank or Person organized under the laws of any other country, or a political subdivision of any such country, which is not a member of the Organization for Economic Cooperation and Development, or (C) any commercial bank or Person organized under the laws of any other country, or a political subdivision of any such country, which is a member of the Organization for Economic Cooperation and Development and has a combined capital and surplus of less than $100,000,000.

“ Environment ” or “ Environmental ” shall have the meanings set forth in 42 U.S.C. 9601(8) (1988).

“ Environmental Claim ” means any third party (including governmental agencies and employees) action, lawsuit, claim, demand, regulatory action or proceeding, order, decree, consent agreement or notice of potential or actual responsibility or violation (including claims or proceedings under the Occupational Safety and Health Acts or similar laws or requirements relating to health or safety of employees) which seeks to impose liability under any Environmental Law.

“ Environmental Law ” means all federal, state, and local laws, rules, regulations, ordinances, orders, decisions, agreements, and other requirements, including common law theories, now or hereafter in effect and relating to, or in connection with the Environment, health, or safety, including without limitation CERCLA, relating to (a) pollution, contamination, injury, destruction, loss, protection, cleanup, reclamation or restoration of the air, surface water, groundwater, land surface or subsurface strata, or other natural resources; (b) solid, gaseous or liquid waste generation, treatment, processing, recycling, reclamation, cleanup, storage, disposal or transportation; (c) exposure to pollutants, contaminants, hazardous, medical infections, or toxic substances, materials or wastes; (d) the safety or health of employees; or (e) the manufacture, processing, handling, transportation, distribution in commerce, use, storage or disposal of hazardous, medical infections, or toxic substances, materials or wastes.

“ Environmental Permit ” means any permit, license, order, approval, registration or other authorization under Environmental Law.

“ ERISA ” means the Employee Retirement Income Security Act of 1974, as amended from time to time.

“ Equity Interest ” means with respect to any Person, any shares, interests, participation, or other equivalents (however designated) of corporate stock, membership interests or partnership interests (or any other ownership interests) of such Person.

“ Eurocurrency Liabilities ” has the meaning assigned to that term in Regulation D of the Federal Reserve Board as in effect from time to time.

“ Event of Default ” has the meaning specified in Section 7.1.

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

“ Excluded Swap Obligation ” means, with respect to any Guarantor, any Hedge Obligation if, and to the extent that, all or a portion of the guaranty of such Guarantor of, or the grant by such Guarantor of a

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security interest to secure, such Hedge Obligation (or any guaranty thereof) is or becomes illegal under the Commodity Exchange Act or any rule, regulation or order of the Commodity Futures Trading Commission (or the application or official interpretation of any thereof) by virtue of such Guarantor’s failure for any reason to constitute an “eligible contract participant” as defined in the Commodity Exchange Act and the regulations thereunder at the time the guaranty of such Guarantor or the grant of such security interest becomes effective with respect to such Hedge Obligation. If a Hedge Obligation arises under a master agreement governing more than one swap, such exclusion shall apply only to the portion of such Hedge Obligation that is attributable to swaps for which such guaranty or security interest is or becomes illegal.

“ Existing Debt ” means Debt incurred by the Borrower in connection with that certain Second Amended and Restated Credit Agreement dated as of December 31, 2000, between the Borrower and Brown Brothers Harriman & Co., as lender.

“ Fair Market Value ” means, with respect to any asset (including any Equity Interests of any Person), the price at which a willing buyer, not an Affiliate of the seller, and a willing seller who does not have to sell, would agree to purchase and sell such asset, as determined in good faith by the board of directors or, pursuant to a specific delegation of authority by such board of directors or a designated senior executive officer, of the Borrower, or the Subsidiary of the Borrower selling such asset.

“ FCPA ” has the meaning set forth in Section 4.20(a).

“ Federal Funds Rate ” means, for any day, the rate per annum equal to the weighted average of the rates on overnight Federal funds transactions with members of the Federal Reserve System arranged by Federal funds brokers on such day, as published by the Federal Reserve Bank of New York on the Business Day next succeeding such day; provided that (a) if such day is not a Business Day, the Federal Funds Rate for such day shall be such rate on such transactions on the next preceding Business Day as so published on the next succeeding Business Day and (b) if no such rate is so published on such next succeeding Business Day, the Federal Funds Rate for such day shall be the average rate charged to the Administrative Agent (in its individual capacity) on such day on such transactions as determined by the Administrative Agent.

“ Federal Reserve Board ” means the Board of Governors of the Federal Reserve System or any of its successors.

“ Fee Letter ” means that certain fee letter dated as of January 29, 2010 between the Borrower and Wells Fargo.

“ Fixed Charges ” means, with respect to any period and with respect to any Person and without duplication, the sum of (a) Interest Expense for such period plus (b) as of the end of such period, the current portion of long term Debt, including the current portion of Capital Leases but excluding the scheduled principal payment of the Revolving Loan due on the Maturity Date plus (c) all Restricted Payments paid (whether in cash or other property, other than Equity Interests that are permitted to be issued by the Borrower under this Agreement) during such period.

“ Fixed Charge Coverage Ratio ” means, as of each fiscal quarter end, the ratio of (a) the amount equal to (i) Borrower’s consolidated EBITDA for the four-fiscal quarter period then ended minus (ii) all federal, state, and local taxes paid in cash or required to be paid in cash during the four-fiscal quarter period then ended minus (iii) Maintenance Capital Expenditures paid or required to be paid during for the four-fiscal quarter period then ended to (b) Fixed Charges for the four-fiscal quarter period then ended.

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“ Foreign Subsidiary ” means any Subsidiary of Borrower that is a “controlled foreign corporation” as defined in Section 957 of the Code.

“ Fund ” means any Person (other than a natural person) that is (or will be) engaged in making, purchasing, holding or otherwise investing in commercial loans and similar extensions of credit in the ordinary course of its activities.

“ GAAP ” means United States of America generally accepted accounting principles as in effect from time to time, applied on a basis consistent with the requirements of Section 1.3.

“ Governmental Authority ” means, with respect to any Person, any foreign governmental authority, the United States of America, any state of the United States of America, the District of Columbia, and any subdivision of any of the foregoing, and any agency, department, commission, board, authority or instrumentality, bureau or court having jurisdiction over such Person.

“ Guarantors ” means any Person that now or hereafter executes a Guaranty, including (a) the Borrower, (b) the Subsidiaries of the Borrower listed on Schedule 4.11; and (c) each Material Domestic Subsidiary or other Subsidiary that becomes a guarantor of all or a portion of the Secured Obligations and which has entered into either a joinder agreement substantially in the form attached to the Guaranty or a new Guaranty.

“ Guaranty ” means the Guaranty Agreement executed in substantially the same form as Exhibit C .

“ Hazardous Substance ” means any substance or material identified as such pursuant to CERCLA and those regulated under any other Environmental Law, including without limitation pollutants, contaminants, petroleum, petroleum products, radionuclides, and radioactive materials.

“ Hazardous Waste ” means any substance or material regulated or designated as such pursuant to any Environmental Law, including without limitation, pollutants, contaminants, flammable substances and materials, explosives, radioactive materials, oil, petroleum and petroleum products, chemical liquids and solids, polychlorinated biphenyls, asbestos, toxic substances, and similar substances and materials.

“ Hedge Obligation ” means, with respect to any Guarantor, any obligation to pay or perform under any agreement, contract or transaction that constitutes a “swap” within the meaning of section 1a(47) of the Commodity Exchange Act.

“ Hedging Arrangement ” means a hedge, call, swap, collar, floor, cap, option, forward sale or purchase or other contract or similar arrangement (including any obligations to purchase or sell any commodity or security at a future date for a specific price) which is entered into to reduce or eliminate or otherwise protect against the risk of fluctuations in prices or rates, including interest rates, foreign exchange rates, commodity prices and securities prices.

“ Interest Expense ” means, for any period and with respect to any Person, total cash interest expense, letter of credit fees and other fees and expenses incurred by such Person in connection with any Debt (including but not limited to Debt under this Agreement) for such period (excluding the arrangement fees and the upfront fees due pursuant to the Fee Letter to the Administrative Agent and the Lenders on or prior to the Effective Date), whether paid or accrued (including that attributable to obligations which have been or should be, in accordance with GAAP, recorded as Capital Leases), including, without limitation, all commissions, discounts, and other fees and charges owed with respect to letters of credit and bankers’ acceptance financing, fees owed with respect to the Secured Obligations, and net costs under Hedging Arrangements entered into addressing interest rates, all as determined in conformity with GAAP.

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“ Interest Period ” means for each LIBOR Advance comprising part of the same Borrowing, the period commencing on the date of such LIBOR Advance is made or deemed made and ending on the last day of the period selected by the Borrower pursuant to the provisions below and Section 2.4, and thereafter, each subsequent period commencing on the day following the last day of the immediately preceding Interest Period and ending on the last day of the period selected by the Borrower pursuant to the provisions below and Section 2.4. The duration of each such Interest Period shall be one, three, or six months, in each case as the Borrower may select, provided that:

(a) Interest Periods commencing on the same date for Advances comprising part of the same Borrowing shall be of the same duration;

(b) whenever the last day of any Interest Period would otherwise occur on a day other than a Business Day, the last day of such Interest Period shall be extended to occur on the next succeeding Business Day, provided that if such extension would cause the last day of such Interest Period to occur in the next following calendar month, the last day of such Interest Period shall occur on the next preceding Business Day;

(c) any Interest Period which begins on the last Business Day of a calendar month (or on a day for which there is no numerically corresponding day in the calendar month at the end of such Interest Period) shall end on the last Business Day of the calendar month in which it would have ended if there were a numerically corresponding day in such calendar month; and

(d) the Borrower may not select any Interest Period for any Advance which ends after the Maturity Date.

“ Inventory ” of any Person means all Property of such Person which would, in accordance with GAAP, be required to be classified and accounted for as inventory on the balance sheet of such Person.

“ Issuing Lender ” means Wells Fargo, in its capacity as the Lender that issues Letters of Credit for the account of any Credit Party pursuant to the terms of this Agreement.

“ Jenkins Bonds ” means the Taxable Industrial Development Revenue Bond (CARBO Ceramics Inc. Project), Series 2012, having a maximum principal amount not to exceed $255,000,000, issued by the Development Authority of Jenkins County.

“ Jenkins Capital Lease Obligations ” means the Debt under the Capital Lease described in Schedule 6.1.

“ Legal Requirement ” means any law, statute, ordinance, decree, requirement, order, judgment, rule, regulation (or official interpretation of any of the foregoing) of, and the terms of any license or permit issued by, any Governmental Authority, including, but not limited to, Regulations T, U and X.

“ Lender Insolvency Event ” means that (a) a Lender or its Parent Company is insolvent, or is generally unable to pay its debts as they become due, or admits in writing its inability to pay its debts as they become due, or makes a general assignment for the benefit of its creditors, or (b) such Lender or its Parent Company is the subject of a bankruptcy, insolvency, reorganization, liquidation or similar proceeding, or a receiver, trustee, conservator, intervenor or sequestrator or the like has been appointed for such Lender or its Parent Company, or such Lender or its Parent Company has taken any action in furtherance of or indicating its consent to or acquiescence in any such proceeding or appointment.

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“ Lenders ” means the Persons listed on the signature pages hereto as Lenders, any other Person that shall have become a Lender hereto pursuant to Section 2.14, and any other Person that shall have become a Lender hereto pursuant to an Assignment and Assumption, but in any event, excluding any such Person that ceases to be a party hereto pursuant to an Assignment and Assumption. Unless the context otherwise requires, the term “Lenders” includes the Swing Line Lender.

“ Lending Office ” means, as to any Lender, the office or offices of such Lender described as such in such Lender’s Administrative Questionnaire, or such other office or offices as a Lender may from time to time notify the Borrower and the Administrative Agent.

“ Letter of Credit ” means any standby or commercial letter of credit issued by the Issuing Lender for the account of a Credit Party pursuant to the terms of this Agreement, in such form as may be agreed by the Borrower and the Issuing Lender.

“ Letter of Credit Application ” means the Issuing Lender standard form letter of credit application for standby or commercial letters of credit which has been executed by the Borrower and accepted by the Issuing Lender in connection with the issuance of a Letter of Credit.

“ Letter of Credit Documents ” means all Letters of Credit, Letter of Credit Applications and amendments thereof, and agreements, documents, and instruments entered into in connection therewith or relating thereto.

“ Letter of Credit Exposure ” means, at the date of its determination by the Administrative Agent, the aggregate outstanding undrawn amount of Letters of Credit plus the aggregate unpaid amount of all of the Borrower’s payment obligations under drawn Letters of Credit.

“ Letter of Credit Maximum Amount ” means $5,000,000; provided that, on and after the Maturity Date, the Letter of Credit Maximum Amount shall be zero.

“ Letter of Credit Obligations ” means any obligations of the Borrower under this Agreement in connection with the Letters of Credit.

“ Leverage Ratio ” means, as of the end of each fiscal quarter, the ratio of (a) all consolidated Debt of the Borrower as of the last day of such fiscal quarter to (b) the Borrower’s consolidated EBITDA for the four-fiscal quarter period then ended.

“ LIBOR Advance ” means an Advance that bears interest based upon the LIBO Rate (other than Advances that bear interest based upon the Daily One Month LIBOR).

“ LIBO Base Rate ” means (a) in determining LIBO Rate for purposes of the “Daily One Month LIBOR”, the rate per annum for Dollar deposits quoted by the Administrative Agent for the purpose of calculating effective rates of interest for loans making reference to the “Daily One-Month LIBOR”, as the inter-bank offered rate in effect from time to time for delivery of funds for one (1) month in amounts approximately equal to the principal amount of the applicable Advances; provided that, the Administrative Agent may base its quotation of the inter-bank offered rate upon such offers or other market indicators of the inter-bank market as the Administrative Agent in its discretion deems appropriate including, but not limited to, the rate determined under the following clause (b), and (b) in determining LIBO Rate for all other purposes, the rate per annum (rounded upward to the nearest whole multiple of 1/8th of 1%) equal to the interest rate per annum set forth on the Reuters Reference LIBOR1 page as the London Interbank Offered Rate, for deposits in Dollars at 11:00 a.m. (London, England time) two Business Days before the first day of the applicable Interest Period and for a period equal to such Interest

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Period; provided that, if such quotation is not available for any reason, then for purposes of this clause (b), LIBO Base Rate shall then be the rate determined by the Administrative Agent to be the rate at which deposits in Dollars for delivery on the first day of such Interest Period in immediately available funds in the approximate amount of the Advances being made, continued or converted by the Lenders and with a term equivalent to such Interest Period would be offered by the Administrative Agent’s London Branch (or other branch or Affiliate of the Administrative Agent) to major banks in the London or other offshore inter-bank market for Dollars at their request at approximately 11:00 a.m. (London time) two Business Days prior to the commencement of such Interest Period; provided further that , if the rate determined under the preceding clause (a) or clause (b) is less than zero, than “LIBO Base Rate” shall be deemed to be zero for such determination.

“ LIBO Rate ” means a rate per annum determined by the Administrative Agent pursuant to the following formula:

Where,

“ LIBO Reserve Percentage ” means, as of any day, the reserve percentage (expressed as a decimal, carried out to five decimal places) in effect on such day, whether or not applicable to any Lender, under regulations issued from time to time by the Federal Reserve Board for determining the maximum reserve requirement (including any emergency, supplemental or other marginal reserve requirement) with respect to liabilities or assets consisting of or including Eurocurrency Liabilities. The LIBO Rate for each outstanding Advance shall be adjusted automatically as of the effective date of any change in the LIBO Reserve Percentage.

“ Lien ” means any mortgage, lien, pledge, charge, deed of trust, security interest, or encumbrance to secure or provide for the payment of any obligation of any Person, whether arising by contract, operation of law, or otherwise (including the interest of a vendor or lessor under any conditional sale agreement, Capital Lease, or other title retention agreement).

“ Liquid Investments ” means (a) readily marketable direct full faith and credit obligations of the United States of America or obligations unconditionally guaranteed by the full faith and credit of the United States of America; (b) commercial paper issued by (i) any Lender or any Affiliate of any Lender or (ii) any commercial banking institutions or corporations rated at least P-1 by Moody’s or A-1 by S&P; (c) certificates of deposit, time deposits, and bankers’ acceptances issued by (i) any of the Lenders or (ii) any other commercial banking institution which is a member of the Federal Reserve System and has a combined capital and surplus and undivided profits of not less than $250,000,000 and rated Aa by Moody’s or AA by S&P; (d) repurchase agreements which are entered into with any of the Lenders or any major money center banks included in the commercial banking institutions described in clause (c) and which are secured by readily marketable direct full faith and credit obligations of the government of the United States of America or any agency thereof; (e) investments in any money market fund which holds investments substantially of the type described in the foregoing clauses (a) through (d); and (f) other investments made through the Administrative Agent or its Affiliates and approved by the Administrative Agent. All the Liquid Investments described in clauses (a) through (d) above shall have maturities of not more than 365 days from the date of issue.

“ Liquidity ” means, as of any date of determination, the sum of (a) an amount equal to (i) the aggregate Commitments in effect at such time, minus (ii) the Outstandings, plus (b) Unrestricted Cash.

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“ Maintenance Capital Expenditure ” means Capital Expenditures made by any Credit Party to maintain the operations of any Credit Party at current levels; provided however, the parties acknowledge that Capital Expenditures made to replace equipment or to extend the life of fixed assets shall constitute Maintenance Capital Expenditures.

“ Majority Lenders ” means (a) other than as provided in clause (b) below, two or more Lenders (other than Lenders that are at such time Defaulting Lenders) holding at least 51% of the sum of (i) the aggregate unfunded Revolving Commitments (excluding the Revolving Commitments of Lenders that are at such time Defaulting Lenders) at such time plus (ii) the aggregate unpaid principal amount of the Revolving Notes (with the aggregate amount of each Lender’s risk participation and funded participation in the Letter of Credit Exposure and Swing Line Advances being deemed as unpaid principal under such Lender’s Revolving Note but excluding the pro rata shares thereof for any Lender that is at such time a Defaulting Lender) and (b) at any time when there is only one Lender or there is only one Lender that is not then a Defaulting Lender, such Lender.

“ Material Adverse Change ” means a material adverse change (a) in the business, financial condition, properties or results of operations of the Borrower and its Subsidiaries, taken as a whole; (b) on the validity or enforceability of this Agreement or any of the other Credit Documents; or (c) on any Credit Party’s ability to perform its obligations under this Agreement, any Note, the Guaranties or any other Credit Document.

“ Material Domestic Subsidiary ” means, as of any fiscal quarter end, any Domestic Subsidiary that (a) has operating income equal to or greater than 10% of the Borrower’s consolidated operating income, in each case, for the four-fiscal quarter period then ended, or (b) has book value of total assets equal to or greater than 10% of the Borrower’s consolidated book value of total assets, in each case under clauses (a) and (b) above, as established in accordance with GAAP and as reflected in the financial statements covering such fiscal quarter and delivered to the Administrative Agent pursuant hereto.

“ Maturity Date ” means the earlier of (a) December 31, 2018 and (b) the earlier termination in whole of the Revolving Commitments pursuant to Section 2.1(b)(i) or Article 7.

“ Maximum Exposure Amount ” means, at any time for each Lender, the sum of (a) the unfunded Revolving Commitment held by such Lender at such time; plus (b) the aggregate unpaid principal amount of the Revolving Note held by such Lender at such time, (with the aggregate amount of such Lender’s risk participation and funded participation in the Letter of Credit Exposure and Swing Line Advances being deemed as unpaid principal under such Lender’s Revolving Note).

“ Maximum Rate ” means the maximum nonusurious interest rate under applicable law.

“ Moody’s ” means Moody’s Investors Service, Inc. and any successor thereto which is a nationally recognized statistical rating organization.

“ Multiemployer Plan ” means a “multiemployer plan” as defined in Section 4001(a)(3) of ERISA to which the Borrower or any member of the Controlled Group is making or accruing an obligation to make contributions.

“ Net Income ” means, for any period and with respect to any Person, the net income for such period for such Person after taxes as determined in accordance with GAAP, excluding, however, (a) extraordinary items, including (i) any net non-cash gain or loss during such period arising from the sale, exchange, retirement or other disposition of capital assets (such term to include all fixed assets and all securities) other than in the ordinary course of business, and (ii) any write-up or write-down of assets

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and (b) the cumulative effect of any change in GAAP; provided that, for purposes of this Agreement, “Net Income” shall not include any net income generated from either the Jenkins Bonds or the Wilkinson Bonds.

“ Net Total Assets ” means, as of any date of determination and without duplication (a) 70% of Receivables of the Borrower and its consolidated Subsidiaries (as reflected on the most recent balance sheet furnished to the Lenders hereunder), plus (b) 40% of the value of Inventory of the Borrower and its consolidated Subsidiaries (as reflected on the most recent balance sheet furnished to the Lenders hereunder), plus (c) 100% of Unrestricted Cash minus (d) consolidated current liabilities of the Borrower and its Subsidiaries (other than (i) Secured Obligations hereunder and (ii) unrealized net losses in the fair market value of any arrangements under Hedging Arrangements, but including any losses attributable to the early extinguishment or conversion of arrangements under Hedging Arrangements or other derivative instruments, in each case, which constitute current liabilities).

“ Net Worth ” means, with respect to any Person as of any date of determination, the excess of the assets of such Person over the sum of the liabilities of such Person and the minority interests of such Person, as determined in accordance with GAAP.

“ Non-Material Domestic Subsidiary ” means any Domestic Subsidiary other than a Material Domestic Subsidiary.

“ Nonordinary Course Asset Sales ” means any sales, conveyances, or other transfers of Property made by any Credit Party (a) of any division of any Credit Party, (b) of the Equity Interest in any direct or indirect Subsidiary or (c) outside the ordinary course of business of such Credit Party, whether in a transaction or related series of transactions.

“ Notes ” means the Revolving Notes and the Swing Line Note.

“ Notice of Borrowing ” means a notice of borrowing signed by the Borrower in substantially the same form as Exhibit D .

“ Notice of Continuation or Conversion ” means a notice of continuation or conversion signed by the Borrower in substantially the same form as Exhibit E .

“ Obligations ” means all principal, interest (including post-petition interest), fees, reimbursements, indemnifications, and other amounts now or hereafter owed by any of the Credit Parties to the Lenders, the Swing Line Lender, the Issuing Lender, or the Administrative Agent under this Agreement and the other Credit Documents, including, the Letter of Credit Obligations, and any increases, extensions, and rearrangements of those obligations under any amendments, supplements, and other modifications of the documents and agreements creating those obligations.

“ OFAC ” has the meaning set forth in Section 4.20(b).

“ Other Taxes ” has the meaning set forth in Section 2.13(b).

“ Outstandings ” means the sum of (a) the outstanding amount of all Revolving Advances plus (b) the outstanding amount of all Swing Line Advances plus (c) the Letter of Credit Exposure.

“ Parent Company ” means, with respect to a Lender, the bank holding company (as defined in Federal Reserve Board Regulation Y), if any, of such Lender, and/or any Person owning, beneficially or of record, directly or indirectly, a majority of the shares of such Lender.

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“ Patriot Act ” means the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)).

“ PBGC ” means the Pension Benefit Guaranty Corporation or any entity succeeding to any or all of its functions under ERISA.

“ Permitted Debt ” has the meaning set forth in Section 6.1.

“ Permitted Investments ” has the meaning set forth in Section 6.3.

“ Permitted Liens ” has the meaning set forth in Section 6.2.

“ Person ” means an individual, partnership, corporation (including a business trust), joint stock company, trust, limited liability company, limited liability partnership, unincorporated association, joint venture, or other entity, or a government or any political subdivision or agency thereof, or any trustee, receiver, custodian, or similar official.

“ Plan ” means an employee benefit plan (other than a Multiemployer Plan) maintained for employees of the Borrower or any member of the Controlled Group and covered by Title IV of ERISA or subject to the minimum funding standards under Section 412 of the Code.

“ Prime Rate ” means the per annum rate of interest established from time to time by the Administrative Agent at its principal office in San Francisco as its prime rate, which rate may not be the lowest rate of interest charged by such Lender to its customers.

“ Potential Defaulting Lender ” means, at any time, a Lender (a) as to which the Administrative Agent has notified the Borrower that an event of the kind referred to in the definition of “Lender Insolvency Event” has occurred and is continuing in respect of any Subsidiary of such Lender, (b) as to which the Administrative Agent or the Issuing Lender has in good faith determined and notified the Borrower (and in the case of the Issuing Lender the Administrative Agent) that such Lender or its Parent Company or a Subsidiary thereof has notified the Administrative Agent, or has stated publicly, that it will not comply with its funding obligations under any other loan agreement or credit agreement or other financing agreement or (c) that has, or whose Parent Company has, a non-investment grade rating from Moody’s or S&P or another nationally recognized rating agency. Any determination that a Lender is a Potential Defaulting Lender will be made by the Administrative Agent or, in the case of clause (b), the Issuing Lender, as the case may be, in its sole discretion acting in good faith. The Administrative Agent will promptly send to all parties hereto a copy of any notice to the Borrower provided for in this definition.

“ Property ” of any Person means any property or assets (whether real, personal, or mixed, tangible or intangible) of such Person.

“ Qualified ECP Guarantor ” means, in respect of any Hedge Obligation, each Guarantor that has total assets exceeding $10,000,000 at the time the relevant guaranty or grant of the relevant security interest becomes effective with respect to such Hedge Obligation or such other person as constitutes an “eligible contract participant” under the Commodity Exchange Act or any regulations promulgated thereunder and can cause another person to qualify as an “eligible contract participant” at such time by entering into a keepwell under Section 1a(18)(A)(v)(II) of the Commodity Exchange Act.

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“ Receivables ” of any Person means, at any date of determination thereof, all Property of such Person which would, in accordance with GAAP, be required to be classified and accounted for as accounts receivable on the balance sheet of such Person.

“ Register ” has the meaning set forth in Section 9.7(b).

“ Regulations T, U, and X ” means Regulations T, U, and X of the Federal Reserve Board, as each is from time to time in effect, and all official rulings and interpretations thereunder or thereof.

“ Release ” shall have the meaning set forth in CERCLA or under any other Environmental Law.

“ Response ” shall have the meaning set forth in CERCLA or under any other Environmental Law.

“ Reportable Event ” means any of the events set forth in Section 4043(c) of ERISA (other than any such event not subject to the provision for 30-day notice to the PBGC under the regulations issued under such section).

“ Responsible Officer ” means (a) with respect to any Person that is a corporation, such Person’s chief financial officer, treasurer or controller, (b) with respect to any Person that is a limited liability company, if such Person has officers, then such Person’s chief financial officer, treasurer or controller, and if such Person is managed by members, then a chief financial officer, treasurer or controller of such Person’s managing member, and if such Person is managed by managers, then a manager (if such manager is an individual) or a Responsible Officer of such manager (if such manager is an entity), and (c) with respect to any Person that is a general partnership, limited partnership or a limited liability partnership, the Responsible Officer of such Person’s general partner or partners.

“ Restricted Payment ” means, with respect to any Person, (a) any direct or indirect dividend or distribution (whether in cash, securities or other Property) or any direct or indirect payment of any kind or character (whether in cash, securities or other Property) in consideration for or otherwise in connection with any Equity Interest of such Person, including in connection with any retirement, purchase, redemption or other acquisition of such Equity Interest, or any options, warrants or rights to purchase or acquire any such Equity Interest or (b) principal or interest payments (in cash, Property or otherwise) on, or redemption of, subordinated debt of such Person; provided that the term “Restricted Payment” shall not include any dividend, distribution, repurchase or redemption payable solely in common Equity Interests or from the proceeds of the contemporaneous issuance of additional common Equity Interests of such Person or warrants, options or other rights to purchase such common Equity Interests.

“ Revolving Advance ” means any advance by a Lender to the Borrower as part of a Revolving Borrowing.

“ Revolving Borrowing ” means a Borrowing consisting of simultaneous Revolving Advances of the same Type made by the Lenders pursuant to Section 2.1(a) or Converted by each Lender to Revolving Advances of a different Type pursuant to Section 2.4(b).

“ Revolving Commitment ” means, for each Lender, the obligation of each Lender to advance to Borrower the amount set opposite such Lender’s name on Schedule II as its Revolving Commitment, or if such Lender has entered into any Assignment and Acceptance, set forth for such Lender as its Revolving Commitment in the Register, as such amount may be reduced pursuant to Section 2.1(b)(i); provided that, after the Maturity Date, the Revolving Commitment for each Lender shall be zero. The initial aggregate Revolving Commitment on the Amendment No. 4 Effective Date is $90,000,000.

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“ Revolving Loan ” means the aggregate principal from a Lender which represents such Lender’s ratable share of a Revolving Borrowing.

“ Revolving Note ” means a promissory note of the Borrower payable to the order of a Lender in the amount of such Lender’s Revolving Commitment, in substantially the same form as Exhibit F -1 , evidencing indebtedness of the Borrower to such Lender resulting from Revolving Advances owing to such Lender.

“ Revolving Pro Rata Share ” means, at any time with respect to any Lender, (a) the ratio (expressed as a percentage) of such Lender’s Revolving Commitment at such time to the aggregate Revolving Commitments at such time, or (b) if all of the Revolving Commitments have been terminated, the ratio (expressed as a percentage) of such Lender’s aggregate outstanding Revolving Advances at such time to the total aggregate outstanding Revolving Advances at such time.

“ Sanctions ” has the meaning set forth in Section 4.20(b).

“ SEC ” means, the Securities and Exchange Commission.

“ Secured Obligations ” means (a) the Obligations, (b) the Banking Services Obligations, (c) the Secured Swap Obligations, and (d) Bilateral Obligations, but in any event, excluding Excluded Swap Obligations.

“ Secured Swap Obligations ” means any and all obligations owing by any Credit Party (whether direct or indirect (including those acquired by assumption), absolute or contingent, due or to become due, now existing or hereafter arising) to any Secured Swap Provider under any Hedging Arrangement between any Credit Party and such Secured Swap Provider, in each case, after giving effect to all netting arrangements relating to such Hedging Arrangement; provided that if such Secured Swap Provider ceases to be a Lender or an Affiliate of a Lender hereunder, Secured Swap Obligations shall only include such obligations to the extent arising from transactions and confirmations entered into under Hedging Arrangements at any time such Secured Swap Provider was a Lender or an Affiliate of a Lender hereunder (including transactions and confirmations entered into under Hedging Arrangements in effect on the Amendment No. 4 Effective Date), without giving effect to any extension, increases, or modifications thereof which are made after such Secured Swap Provider ceases to be a Lender or an Affiliate of a Lender hereunder.

“ Secured Swap Provider ” means any Person that is a party to a Hedging Arrangement with any Credit Party if (a) at the time such Hedging Arrangement was entered into or assumed, such Person was a Lender or an Affiliate of a Lender hereunder, even if such Person subsequently ceases to be a Lender (or an Affiliate thereof) for any reason or (b) such Hedging Arrangement was in effect on the Amendment No. 4 Effective Date and such Person or an Affiliate of such Person was a Lender on the Amendment No. 4 Effective Date, even if such Person subsequently ceases to be a Lender (or an Affiliate thereof) for any reason.

“ Secured Parties ” means the Administrative Agent, the Issuing Lender, the Lenders, the Secured Swap Providers and Banking Services Providers.

“ Security Agreement ” means the Pledge and Security Agreement among the Credit Parties and the Administrative Agent in such form acceptable to the Administrative Agent.

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“ Security Documents ” means, collectively, the Security Agreement, and any and all other instruments, documents or agreements, now or hereafter executed by any Credit Party or any other Person to secure the Secured Obligations.

“ S&P ” means Standard & Poor’s Rating Agency Group, a division of McGraw-Hill Companies, Inc., or any successor thereof which is a national credit rating organization.

“ Solvent ” means, as to any Person, on the date of any determination (a) the fair value of the Property of such Person is greater than the total amount of debts and other liabilities (including without limitation, contingent liabilities) of such Person, (b) the present fair salable value of the assets of such Person is not less than the amount that will be required to pay the probable liability of such Person on its debts and other liabilities (including, without limitation, contingent liabilities) as they become absolute and matured, (c) such Person is able to realize upon its assets and pay its debts and other liabilities (including, without limitation, contingent liabilities) as they mature in the normal course of business, (d) such Person does not intend to, and does not believe that it will, incur debts or liabilities (including, without limitation, contingent liabilities) beyond such Person’s ability to pay as such debts and liabilities mature, (e) such Person is not engaged in, and is not about to engage in, business or a transaction for which such Person’s Property would constitute unreasonably small capital, and (f) such Person has not transferred, concealed or removed any Property with intent to hinder, delay or defraud any creditor of such Person.

“ Subject Lender ” has the meaning set forth in Section 2.14.

“ Subsidiary ” means, with respect to any Person (the “ holder ”) at any date, any corporation, limited liability company, partnership, association or other entity the accounts of which would be consolidated with those of the holder in the holder’s consolidated financial statements if such financial statements were prepared in accordance with GAAP as of such date, as well as any other corporation, limited liability company, partnership, association or other entity, a majority of whose outstanding Voting Securities shall at any time be owned by the holder or one more Subsidiaries of the holder. Unless expressly provided otherwise, all references herein and in any other Credit Document to any “Subsidiary” or “Subsidiaries” means a Subsidiary or Subsidiaries of the Borrower.

“ Swing Line Advance ” means an advance by the Swing Line Lender to the Borrower as part of a Swing Line Borrowing.

“ Swing Line Borrowing ” means the Borrowing consisting of a Swing Line Advance made by the Swing Line Lender pursuant to Section 2.3 or, if an AutoBorrow Agreement is in effect, any transfer of funds pursuant to such AutoBorrow Agreement.

“ Swing Line Sublimit Amount ” means $5,000,000; provided that, on and after the Maturity Date, the Swing Line Sublimit Amount shall be zero.

“ Swing Line Lender ” means Wells Fargo.

“ Swing Line Note ” means the promissory note made by the Borrower payable to the order of the Swing Line Lender evidencing the indebtedness of the Borrower to the Swing Line Lender resulting from Swing Line Advances in substantially the same form as Exhibit F-2 .

“ Swing Line Payment Date ” means (a) if an AutoBorrow Agreement is in effect, the earliest to occur of (i) the date required by such AutoBorrow Agreement, (ii) demand is made by the Swing Line Lender and (iii) the Maturity Date, or (b) if an AutoBorrow Agreement is not in effect, the earlier to occur of (i) three (3) Business Days after demand is made by the Swing Line Lender if no Default exists, and otherwise upon demand by the Swing Line Lender and (ii) the Maturity Date.

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“ Tangible Net Worth ” means, as to the Borrower, (i) the consolidated shareholder’s (or other type of equity holder’s) equity of the Borrower and its Subsidiaries (determined in accordance with GAAP), less (ii) the amount of consolidated intangible assets (as defined under GAAP) of the Borrower and its Subsidiaries.

“ Taxes ” has the meaning set forth in Section 2.13(a).

“ Termination Event ” means (a) a Reportable Event with respect to a Plan, (b) the withdrawal of the Borrower or any member of the Controlled Group from a Plan during a plan year in which it was a “substantial employer” as defined in Section 4001(a)(2) of ERISA, (c) the filing of a notice of intent to terminate a Plan or the treatment of a Plan amendment as a termination under Section 4041(c) of ERISA, (d) the institution of proceedings to terminate a Plan by the PBGC, or (e) any other event or condition which constitutes grounds under Section 4042 of ERISA for the termination of, or the appointment of a trustee to administer, any Plan.

“ Treasury Management Arrangement ” means any agreement or other arrangement governing the provision of treasury or cash management services, including deposit accounts, overdraft, credit or debit card, funds transfer, automated clearinghouse, zero balance accounts, returned check concentration, controlled disbursement, lockbox, account reconciliation and reporting and trade finance services and other cash management services

“ Type ” has the meaning set forth in Section 1.4.

“ Unrestricted Cash ” means, as of any date of determination, the readily and immediately available cash that would not appear as “restricted” on the balance sheet of the Borrower and its Subsidiaries and held in deposit accounts of any Credit Party (other than the Cash Collateral Account) on such date; provided that, such deposit accounts and the funds therein shall be unencumbered and free and clear of all Liens and other third party rights other than (a) a Lien in favor of the Administrative Agent pursuant to Security Documents and (b) a Lien in favor of the depositary institution holding such deposit accounts arising solely by virtue of such depositary institution’s standard account documentation or any statutory or common law provision relating to banker’s liens, rights of set-off or similar rights and remedies and burdening only such deposit accounts.

“ Voting Securities ” means (a) with respect to any corporation, capital stock of the corporation having general voting power under ordinary circumstances to elect directors of such corporation (irrespective of whether at the time stock of any other class or classes shall have or might have special voting power or rights by reason of the happening of any contingency), (b) with respect to any partnership, any partnership interest or other ownership interest having general voting power to elect the general partner or other management of the partnership or other Person, and (c) with respect to any limited liability company, membership certificates or interests having general voting power under ordinary circumstances to elect managers of such limited liability company.

“ Wells Fargo ” means Wells Fargo Bank, National Association.

“ Wilkinson Bonds ” means the Taxable Industrial Development Revenue Bond (Carbo Ceramics Inc. Project), Series 2008, having a maximum principal amount not to exceed $410,000,000, issued by the Development Authority of Wilkinson County.

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“ Wilkinson Capital Lease Obligations ” means the Debt under the Capital Lease described in Schedule 6.1.

Section 1.2 Computation of Time Periods . In this Agreement in the computation of periods of time from a specified date to a later specified date, the word “from” means “from and including” and the words “to” and “until” each means “to but excluding”.

Section 1.3 Accounting Terms; Changes in GAAP .

(a) All accounting terms not specifically defined in this Agreement shall be construed in accordance with GAAP applied on a consistent basis with those applied in the preparation of the financial statements delivered to the Administrative Agent for the fiscal year ending December 31, 2008 as required under Section 5.2.

(b) Unless otherwise indicated, all financial statements of the Borrower, all calculations for compliance with covenants in this Agreement, all determinations of the Applicable Margin, and all calculations of any amounts to be calculated under the definitions in Section 1.1 shall be based upon the consolidated accounts of the Borrower and its Subsidiaries in accordance with GAAP and consistent with the principles of consolidation applied in preparing the Borrower’s financial statements referred to in Section 4.4.

(c) If at any time any change in GAAP would affect the computation of any financial ratio or requirement set forth in any Credit Document, and either the Borrower or the Majority Lenders shall so request, the Administrative Agent, the Lenders and the Borrower shall negotiate in good faith to amend such ratio or requirement to preserve the original intent thereof in light of such change in GAAP (subject to the approval of the Majority Lenders); provided that , until so amended, (i) such ratio or requirement shall continue to be computed in accordance with GAAP prior to such change therein and (ii) the Borrower shall provide to the Administrative Agent and the Lenders financial statements and other documents required under this Agreement or as reasonably requested hereunder setting forth a reconciliation between calculations of such ratio or requirement made before and after giving effect to such change in GAAP.

Section 1.4 Classes and Types of Advances . Advances are distinguished by “Class” and “Type”. The “Class” of an Advance refers to the determination of whether such Advance is a Revolving Advance or a Swing Line Advance. The “Type” of an Advance refers to the determination of whether such Advance is a Base Rate Advance or a LIBOR Advance.

Section 1.5 Miscellaneous . Article, Section, Schedule, and Exhibit references are to this Agreement, unless otherwise specified. All references to instruments, documents, contracts, and agreements (including this Agreement) 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 and shall include all schedules and exhibits thereto unless otherwise specified. Any reference herein to any law shall be construed as referring to such law as amended, modified, codified or reenacted, in whole or in part, and in effect from time to time. Any reference herein to any Person shall be construed to include such Person’s successors and assigns (subject to the restrictions contained herein). The words “hereof”, “herein”, and “hereunder” and words of similar import when used in this Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement. The term “including” means “including, without limitation,”. Paragraph headings have been inserted in this Agreement as a matter of convenience for reference only and it is agreed that such paragraph headings are not a part of this Agreement and shall not be used in the interpretation of any provision of this Agreement.

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ARTICLE 2

CREDIT FACILITIES

Section 2.1 Revolving Commitments .

(a) Revolving Commitment . Each Lender severally agrees, on the terms and conditions set forth in this Agreement, to make Revolving Advances to the Borrower from time to time on any Business Day during the period from the Effective Date until the Maturity Date; provided that after giving effect to such Revolving Advances, the Outstandings shall not exceed the aggregate Revolving Commitments in effect at such time. Each Revolving Borrowing shall (A) if comprised of Base Rate Advances be in an aggregate amount not less than $100,000 and in integral multiples of $100,000 in excess thereof, (B) if comprised of LIBOR Advances be in an aggregate amount not less than $200,000 and in integral multiples of $100,000 in excess thereof, and (C) consist of Revolving Advances of the same Type made on the same day by the Lenders ratably according to their respective Revolving Commitments. Within the limits of each Lender’s Revolving Commitment, the Borrower may from time to time borrow, prepay pursuant to Section 2.5, and reborrow under this Section 2.1(a).

(b) Reduction of the Commitments .

(i) Revolving Commitments . The Borrower shall have the right, upon at least three Business Days’ irrevocable notice to the Administrative Agent, to terminate in whole or reduce in part the unused portion of the Revolving Commitments; provided that each partial reduction shall be in a minimum amount of $200,000 and in integral multiples of $100,000 in excess thereof. Other than as provided in Section 2.1(b)(ii) below, any reduction or termination of the Commitments pursuant to this Section 2.1(a)(i) shall be applied ratably to each Lender’s Revolving Commitment and shall be permanent, with no obligation of the Lenders to reinstate such Revolving Commitments, and the Commitment Fees shall thereafter be computed on the basis of the aggregate Revolving Commitments, as so reduced. If there are no outstanding Revolving Commitments, Letters of Credit, expenses, fees or any other amounts owing pursuant to any Credit Document, the Borrower shall have the right, upon at least one Business Day’s notice to the Administrative Agent, to terminate this Agreement except the terms hereof which expressly state that such terms survive the termination of this Agreement or the termination of the Revolving Commitments.

(ii) Defaulting Lender . At any time when a Lender is then a Defaulting Lender, the Borrower, at the Borrower’s election, may terminate such Defaulting Lender’s Revolving Commitment hereunder; provided that (A) such termination must be of the Defaulting Lender’s entire Revolving Commitment, (B) the Borrower shall pay all amounts owed by the Borrower to such Defaulting Lender in such Lender’s capacity as a Lender under this Agreement and under the other Credit Documents (including principal of and interest on the Revolving Advances owed to such Defaulting Lender, accrued commitment fees (subject to Section 2.7(a)), and letter of credit fees but specifically excluding any amounts owing under Section 2.10 as result of such payment of Revolving Advances) and shall deposit with the Administrative Agent into the Cash Collateral Account cash collateral in the amount equal to such Defaulting Lender’s ratable share of the Letter of Credit Exposure, (C) a Defaulting Lender’s Revolving Commitment may be terminated by the Borrower under this Section 2.1(b)(ii) if and only if at such time, the Borrower has elected, or is then electing, to terminate the Revolving Commitments of all then existing Defaulting Lenders. Upon written notice to the Defaulting Lender and Administrative Agent of the Borrower’s election to terminate a Defaulting Lender’s Revolving Commitment pursuant to this clause (ii) and the payment and deposit of amounts required to be made by the Borrower

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under clause (B) above, (1) such Defaulting Lender shall cease to be a “Lender” hereunder for all purposes except that such Lender’s rights as a Lender under Sections 2.11, 2.13, 8.5 and 9.2 shall continue with respect to events and occurrences occurring before or concurrently with its ceasing to be a “Lender” hereunder, (2) such Defaulting Lender’s Revolving Commitment shall be deemed terminated, and (3) such Defaulting Lender shall be relieved of its obligations hereunder as a “Lender”.

(c) Notes . The indebtedness of the Borrower to each Lender resulting (i) from Revolving Advances owing to such Lender shall be evidenced by a Revolving Note and (ii) from Swing Line Advances owing to the Swing Line Lender, as set forth in Section 2.3 below, shall be evidenced by a Swing Line Note.

Section 2.2 Letters of Credit

(a) Commitment for Letters of Credit . Subject to the terms and conditions set forth in this Agreement, the Issuing Lender agrees, in reliance upon the agreements of the other Lenders set forth in this Section 2.2, from time to time on any Business Day during the period from the Effective Date until the date that is 10 days prior to the Maturity Date, to issue, increase or extend the expiration date of, Letters of Credit for the account of any Credit Party, provided that no Letter of Credit will be issued, increased, or extended:

(i) if such issuance, increase, or extension would cause the Letter of Credit Exposure to exceed the lesser of (A) the Letter of Credit Maximum Amount and (B) an amount equal to (1) the aggregate Revolving Commitments in effect at such time minus (2) the sum of the aggregate outstanding amount of all Revolving Advances plus the aggregate outstanding amount of all Swing Line Advances;

(ii) unless such Letter of Credit has an expiration date not later than 10 days prior to the Maturity Date; provided that, if Revolving Commitments are terminated in whole pursuant to Section 2.1(b)(i), the Borrower shall, at its election, either (A) deposit into the Cash Collateral Account cash in an amount equal to 105% of the Letter of Credit Exposure for the Letters of Credit which have an expiry date beyond the Maturity Date or (B) provide a replacement letter of credit (or other security) reasonably acceptable to the Administrative Agent and the Issuing Lender in an amount equal to 105% of the Letter of Credit Exposure;

(iii) unless such Letter of Credit is (A) a standby letter of credit not supporting the repayment of indebtedness for borrowed money of any Person, or (B) with the consent of the Issuing Lender (such consent not to be unreasonably withheld) and so long as the Borrower as agreed to such additional reasonable fees which may apply, a commercial letter of credit;

(iv) unless such Letter of Credit is in form and substance acceptable to the Issuing Lender in its sole discretion;

(v) unless the Borrower has delivered to the Issuing Lender a completed and executed Letter of Credit Application; provided that, if the terms of any Letter of Credit Application conflicts with the terms of this Agreement, the terms of this Agreement shall control;

(vi) unless such Letter of Credit is governed by (A) the Uniform Customs and Practice for Documentary Credits (2007 Revision), International Chamber of Commerce Publication No. 600, or (B) the International Standby Practices (ISP98), International Chamber of Commerce Publication No. 590, in either case, including any subsequent revisions thereof approved by a Congress of the International Chamber of Commerce and adhered to by the Issuing Lender;

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(vii) if any order, judgment or decree of any Governmental Authority or arbitrator shall by its terms purport to enjoin or restrain the Issuing Lender from issuing, increasing or extending such Letter of Credit, or any Legal Requirement applicable to the Issuing Lender or any request or directive (whether or not having the force of law) from any Governmental Authority with jurisdiction over the Issuing Lender shall prohibit, or request that the Issuing Lender refrain from, the issuance, increase or extension of letters of credit generally or such Letter of Credit in particular or shall impose upon the Issuing Lender with respect to such Letter of Credit any restriction, reserve or capital requirement (for which the Issuing Lender is not otherwise compensated hereunder) not in effect on the Effective Date, or shall impose upon the Issuing Lender any unreimbursed loss, cost or expense which was not applicable on the Effective Date and which the Issuing Lender in good faith deems material to it;

(viii) if the issuance, increase or extension of such Letter of Credit would violate one or more policies of the Issuing Lender applicable to letters of credit generally;

(ix) if Letter of Credit is to be denominated in a currency other than Dollars; or

(x) any Lender is at such time a Defaulting Lender or a Potential Defaulting Lender hereunder, unless the Issuing Lender has entered into satisfactory arrangements with the Borrower or such Lender to eliminate the Issuing Lender’s risk with respect to such Lender.

Furthermore, anything contained herein to the contrary notwithstanding, the Issuing Lender may, but shall not be obligated to, issue or cause the issuance of a Letter of Credit that supports the obligations of the Borrower or its Subsidiaries in respect of (1) a lease of real property, or (2) an employment contract.

(b) Requesting Letters of Credit . Each Letter of Credit shall be issued pursuant to a Letter of Credit Application given by the Borrower to the Administrative Agent for the benefit of the Issuing Lender by facsimile or other writing not later than 11:00 a.m. (Houston, Texas, time) on the third Business Day before the proposed date of issuance for the Letter of Credit. Each Letter of Credit Application shall be fully completed and shall specify the information required therein. Each Letter of Credit Application shall be irrevocable and binding on the Borrower. Subject to the terms and conditions hereof, the Issuing Lender shall before 2:00 p.m. (Houston, Texas, time) on the date of such Letter of Credit issue such Letter of Credit to the beneficiary of such Letter of Credit.

(c) Reimbursements for Letters of Credit; Funding of Participations .

(i) With respect to any Letter of Credit, in accordance with the related Letter of Credit Application, the Borrower agrees to pay on demand to the Administrative Agent on behalf of the Issuing Lender an amount equal to any amount paid by the Issuing Lender under such Letter of Credit. Upon the Issuing Lender’s demand for payment under the terms of a Letter of Credit Application, the Borrower may, with a written notice, request that the Borrower’s obligations to the Issuing Lender thereunder be satisfied with the proceeds of a Revolving Advance in the same amount (notwithstanding any minimum size or increment limitations on individual Revolving Advances). If the Borrower does not make such request and does not otherwise make the payments demanded by the Issuing Lender as required under this Agreement or the Letter of Credit Application, then the Borrower shall be deemed for all purposes of this Agreement to have requested such a Revolving Advance in the same amount and the transfer of the proceeds thereof to satisfy the Borrower’s obligations to the Issuing Lender, and the Borrower

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hereby unconditionally and irrevocably authorizes, empowers, and directs the Lenders to make such Revolving Advance, to transfer the proceeds thereof to the Issuing Lender in satisfaction of such obligations, and to record and otherwise treat such payments as a Revolving Advance to the Borrower. The Administrative Agent and each Lender may record and otherwise treat the making of such Revolving Borrowings as the making of a Revolving Borrowing to the Borrower under this Agreement as if requested by the Borrower. Nothing herein is intended to release any of the Borrower’s obligations under any Letter of Credit Application, but only to provide an additional method of payment therefor. The making of any Borrowing under this Section 2.2(c) shall not constitute a cure or waiver of any Default, other than the payment Default which is satisfied by the application of the amounts deemed advanced hereunder, caused by the Borrower’s failure to comply with the provisions of this Agreement or the Letter of Credit Application.

(ii) Each Lender (including the Lender acting as Issuing Lender) shall, upon notice from the Administrative Agent that the Borrower has requested or is deemed to have requested a Revolving Advance pursuant to Section 2.4 and regardless of whether (A) the conditions in Section 3.2 have been met, (B) such notice complies with Section 2.4, or (C) a Default exists, make funds available to the Administrative Agent for the account of the Issuing Lender in an amount equal to such Lender’s Revolving Pro Rata Share of the amount of such Revolving Advance not later than 1:00 p.m. on the Business Day specified in such notice by the Administrative Agent, whereupon each Lender that so makes funds available shall be deemed to have made a Revolving Advance to the Borrower in such amount. The Administrative Agent shall remit the funds so received to the Issuing Lender.

(iii) If any such Lender shall not have so made its Revolving Advance available to the Administrative Agent pursuant to this Section 2.2, such Lender agrees to pay interest thereon for each day from such date until the date such amount is paid at the lesser of (A) the Federal Funds Rate for such day for the first three days and thereafter the interest rate applicable to the Revolving Advance and (B) the Maximum Rate. Whenever, at any time after the Administrative Agent has received from any Lender such Lender’s Revolving Advance, the Administrative Agent receives any payment on account thereof, the Administrative Agent will pay to such Lender its participating interest in such amount (appropriately adjusted, in the case of interest payments, to reflect the period of time during which such Lender’s Revolving Advance was outstanding and funded), which payment shall be subject to repayment by such Lender if such payment received by the Administrative Agent is required to be returned. Each Lender’s obligation to make the Revolving Advance pursuant to this Section 2.2 shall be absolute and unconditional and shall not be affected by any circumstance, including (1) any set-off, counterclaim, recoupment, defense or other right which such Lender or any other Person may have against the Issuing Lender, the Administrative Agent or any other Person for any reason whatsoever; (2) the occurrence or continuance of a Default or the termination of the Revolving Commitments; (3) any breach of this Agreement by any Credit Party or any other Lender; or (4) any other circumstance, happening or event whatsoever, whether or not similar to any of the foregoing.

(d) Participations . Upon the date of the issuance or increase of a Letter of Credit under Section 2.2(a), the Issuing Lender shall be deemed to have sold to each other Lender and each other Lender shall have been deemed to have purchased from the Issuing Lender a participation in the related Letter of Credit Obligations equal to such Lender’s Revolving Pro Rata Share at such date and such sale and purchase shall otherwise be in accordance with the terms of this Agreement. The Issuing Lender shall promptly notify each such participant Lender by telex, telephone, or telecopy of each Letter of Credit issued or increased and the actual dollar amount of such Lender’s participation in such Letter of Credit.

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(e) Obligations Unconditional . The obligations of the Borrower under this Agreement in respect of each Letter of Credit shall be unconditional and irrevocable, and shall be paid strictly in accordance with the terms of this Agreement under all circumstances, notwithstanding the following circumstances:

(i) any lack of validity or enforceability of any Letter of Credit Documents;

(ii) any amendment or waiver of or any consent to departure from any Letter of Credit Documents;

(iii) the existence of any claim, set-off, defense or other right which any Credit Party may have at any time against any beneficiary or transferee of such Letter of Credit (or any Persons for whom any such beneficiary or any such transferee may be acting), the Issuing Lender, any Lender or any other person or entity, whether in connection with this Agreement, the transactions contemplated in this Agreement or in any Letter of Credit Documents or any unrelated transaction;

(iv) any statement or any other document presented under such Letter of Credit proving to be forged, fraudulent, invalid or insufficient in any respect or any statement therein being untrue or inaccurate in any respect to the extent the Issuing Lender would not be liable therefor pursuant to the following paragraph (g);

(v) payment by the Issuing Lender under such Letter of Credit against presentation of a draft or certificate which does not comply with the terms of such Letter of Credit; or

(vi) any other circumstance or happening whatsoever, whether or not similar to any of the foregoing;

provided , however, that nothing contained in this paragraph (e) shall be deemed to constitute a waiver of any remedies of the Borrower in connection with the Letters of Credit.

(f) Prepayments of Letters of Credit . In the event that any Letter of Credit shall be outstanding or shall be drawn and not reimbursed on or prior to the 5 ^th Business Day prior to the Maturity Date, the Borrower shall pay to the Administrative Agent an amount equal to 105% of the Letter of Credit Exposure allocable to such Letter of Credit, such amount to be due and payable on the 5 ^th Business Day prior to the Maturity Date, and to be held in the Cash Collateral Account and applied in accordance with paragraph (h) below.

(g) Liability of Issuing Lender . The Borrower assumes all risks of the acts or omissions of any beneficiary or transferee of any Letter of Credit with respect to its use of such Letter of Credit. Neither the Issuing Lender nor any of its officers or directors shall be liable or responsible for:

(i) the use which may be made of any Letter of Credit or any acts or omissions of any beneficiary or transferee in connection therewith;

(ii) the validity, sufficiency or genuineness of documents, or of any endorsement thereon, even if such documents should prove to be in any or all respects invalid, insufficient, fraudulent or forged;

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(iii) payment by the Issuing Lender against presentation of documents which do not comply with the terms of a Letter of Credit, including failure of any documents to bear any reference or adequate reference to the relevant Letter of Credit; or

(iv) any other circumstances whatsoever in making or failing to make payment under any Letter of Credit ( INCLUDING THE ISSUING LENDER’S OWN NEGLIGENCE ),

except that the Borrower shall have a claim against the Issuing Lender, and the Issuing Lender shall be liable to, and shall promptly pay to, the Borrower, to the extent of any direct, as opposed to consequential, damages suffered by the Borrower which the Borrower proves were caused by (A) the Issuing Lender’s willful misconduct or gross negligence in determining whether documents presented under a Letter of Credit comply with the terms of such Letter of Credit or (B) the Issuing Lender’s willful failure to make lawful payment under any Letter of Credit after the presentation to it of a draft and certificate strictly complying with the terms and conditions of such Letter of Credit. In furtherance and not in limitation of the foregoing, the Issuing Lender may accept documents that appear on their face to be in order, without responsibility for further investigation, regardless of any notice or information to the contrary.

(h) Cash Collateral Account .

(i) If the Borrower is required to deposit funds in the Cash Collateral Account pursuant to Sections 2.2(f), 2.2(i), 2.5(c), 7.2(b) or 7.3(b), then the Borrower and the Administrative Agent shall establish the Cash Collateral Account and the Borrower shall execute any documents and agreements, including the Administrative Agent’s standard form assignment of deposit accounts, that the Administrative Agent reasonably requests in connection therewith to establish the Cash Collateral Account and grant the Administrative Agent an Acceptable Security Interest in such account and the funds therein. The Borrower hereby pledges to the Administrative Agent and grants the Administrative Agent, for the ratable benefit of the Secured Parties, a security interest in the Cash Collateral Account, whenever established, all funds held in the Cash Collateral Account from time to time, and all proceeds thereof as security for the payment of the Secured Obligations.

(ii) Funds held in the Cash Collateral Account shall be held as cash collateral for obligations with respect to Letters of Credit and promptly applied by the Administrative Agent at the request of the Issuing Lender to any reimbursement or other obligations under Letters of Credit that exist or occur. To the extent that any surplus funds are held in the Cash Collateral Account above the Letter of Credit Exposure during the existence of an Event of Default the Administrative Agent may (A) hold such surplus funds in the Cash Collateral Account as cash collateral for the Secured Obligations or (B) apply such surplus funds to any Secured Obligations in any manner directed by the Majority Lenders. If no Default exists, the Administrative Agent shall release any surplus funds held in the Cash Collateral Account above the Letter of Credit Exposure to the Borrower promptly following the Borrower’s written request. Notwithstanding the foregoing, if the Borrower has complied with the terms of Section 2.2(i) and no Default exists, or would result therefrom, the Administrative Agent shall release the funds deposited by the Borrower pursuant to Section 2.2(i) to the Borrower promptly following the Borrower’s written request.

(iii) Funds held in the Cash Collateral Account may be invested (for the benefit of the Borrower) in Liquid Investments maintained with, and under the sole dominion and control of, the Administrative Agent or in another investment if mutually agreed upon by the Borrower and the Administrative Agent, but the Administrative Agent shall have no obligation to make any investment of the funds therein. The Administrative Agent shall exercise reasonable care in the

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custody and preservation of any funds held in the Cash Collateral Account and shall be deemed to have exercised such care if such funds are accorded treatment substantially equivalent to that which the Administrative Agent accords its own property, it being understood that the Administrative Agent shall not have any responsibility for taking any necessary steps to preserve rights against any parties with respect to any such funds.

(i) Defaulting Lender . If, at any time, a Defaulting Lender or a Potential Defaulting Lender exists hereunder, then, at the request of the Issuing Lender, the Borrower shall deposit funds with Administrative Agent into the Cash Collateral Account an amount equal to such Defaulting Lender’s or Potential Defaulting Lender’s pro rata share of the Letter of Credit Exposure.

(j) Letters of Credit Issued for Guarantors or any Subsidiary . Notwithstanding that a Letter of Credit issued or outstanding hereunder is in support of any obligations of, or is for the account of, a Guarantor or any Subsidiary, the Borrower shall be obligated to reimburse the Issuing Lender hereunder for any and all drawings under such Letter of Credit issued hereunder by the Issuing Lender. The Borrower hereby acknowledges that the issuance of Letters of Credit for the account of any Guarantor, the Borrower or any Subsidiary inures to the benefit of the Borrower, and that the Borrower’s business (indirectly or directly) derives substantial benefits from the businesses of such other Persons.

Section 2.3 Swing Line Advances .

(a) Facility . On the terms and conditions set forth in this Agreement, and if an AutoBorrow Agreement is in effect, subject to the terms and conditions of such AutoBorrow Agreement, the Swing Line Lender may, in its sole discretion, from time-to-time on any Business Day during the period from the date of this Agreement until the last Business Day occurring before the Maturity Date, make Swing Line Advances under the Swing Line Note to the Borrower which shall be due and payable on the Swing Line Payment Date (except that no Swing Line Advance may mature after the Maturity Date), bearing interest at the Adjusted Base Rate plus the Applicable Margin for Base Rate Advances, and in an aggregate outstanding principal amount not to exceed the Swing Line Sublimit Amount at any time; provided that (i) after giving effect to such Swing Line Advance, the Outstandings shall not exceed the aggregate Revolving Commitments in effect at such time; (ii) no Swing Line Advance shall be made by the Swing Line Lender if the conditions set forth in Section 3.2 have not been met as of the date of such Swing Line Advance, it being agreed by the Borrower that the giving of the applicable Notice of Borrowing and the acceptance by the Borrower of the proceeds of such Swing Line Advance shall constitute a representation and warranty by the Borrower that on the date of such Swing Line Advance such conditions have been met; and (iii) if an AutoBorrow Agreement is in effect, such additional terms and conditions of such AutoBorrow Agreement shall have been satisfied, and in the event that any of the terms of this Section 2.3(a) conflict with such AutoBorrow Agreement, the terms of the AutoBorrow Agreement shall govern and control. The indebtedness of the Borrower to the Swing Line Lender resulting from Swing Line Advances shall be evidenced by the Swing Line Note. No Lender shall have any rights or obligations under any AutoBorrow Agreement, but each Lender shall have the obligation to purchase and fund risk participations in the Swing Line Advances and to refinance Swing Line Advances as provided below.

(b) Prepayment . Within the limits expressed in this Agreement, amounts advanced pursuant to Section 2.3(a) may from time to time be borrowed, prepaid without penalty, and reborrowed. If the aggregate outstanding principal amount of the Swing Line Advances ever exceeds the Swing Line Sublimit Amount, the Borrower shall, upon receipt of written notice of such condition from the Swing Line Lender and to the extent of such excess, prepay to the Swing Line Lender outstanding principal of the Swing Line Advances such that such excess is eliminated. If an AutoBorrow Agreement is in effect, each prepayment of a Swing Line Borrowing shall be made as provided in such AutoBorrow Agreement.

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(c) Reimbursements for Swing Line Obligations .

(i) With respect to the Swing Line Advances and the interest, premium, fees, and other amounts owed by the Borrower to the Swing Line Lender in connection with the Swing Line Advances, the Borrower agrees to pay to the Swing Line Lender such amounts when due and payable to the Swing Line Lender under the terms of this Agreement and, if an AutoBorrow Agreement is in effect, in accordance with the terms of such AutoBorrow Agreement. If the Borrower does not pay to the Swing Line Lender any such amounts when due and payable to the Swing Line Lender, the Swing Line Lender may upon notice to the Administrative Agent request the satisfaction of such obligation by the making of a Revolving Borrowing in the amount of any such amounts not paid when due and payable. Upon such request, the Borrower shall be deemed to have requested the making of a Revolving Borrowing in the amount of such obligation and the transfer of the proceeds thereof to the Swing Line Lender. Such Revolving Borrowing shall bear interest based upon the Adjusted Base Rate plus the Applicable Margin for Base Rate Advances. The Administrative Agent shall promptly forward notice of such Revolving Borrowing to the Borrower and the Lenders, and each Lender shall, regardless of whether (A) the conditions in Section 3.2 have been met, (B) such notice complies with Section 2.4, or (C) a Default exists, make available such Lender’s ratable share of such Revolving Borrowing to the Administrative Agent, and the Administrative Agent shall promptly deliver the proceeds thereof to the Swing Line Lender for application to such amounts owed to the Swing Line Lender. The Borrower hereby unconditionally and irrevocably authorizes, empowers, and directs the Swing Line Lender to make such requests for Revolving Borrowings on behalf of the Borrower, and the Lenders to make Revolving Advances to the Administrative Agent for the benefit of the Swing Line Lender in satisfaction of such obligations. The Administrative Agent and each Lender may record and otherwise treat the making of such Revolving Borrowings as the making of a Revolving Borrowing to the Borrower under this Agreement as if requested by the Borrower. Nothing herein is intended to release the Borrower’s obligations under the Swing Line Note, but only to provide an additional method of payment therefor. The making of any Borrowing under this Section 2.3(c) shall not constitute a cure or waiver of any Default or Event of Default, other than the payment Default or Event of Default which is satisfied by the application of the amounts deemed advanced hereunder, caused by the Borrower’s failure to comply with the provisions of this Agreement or the Swing Line Note.

(ii) If at any time, the Revolving Commitments shall have expired or be terminated while any Swing Line Advance is outstanding, each Lender, at the sole option of the Swing Line Lender, shall either (A) notwithstanding the expiration or termination of the Revolving Commitments, make a Revolving Advance as a Base Rate Advance, or (B) be deemed, without further action by any Person, to have purchased from the Swing Line Lender a participation in such Swing Line Advance, in either case in an amount equal to the product of such Lender’s Revolving Pro Rata Share times the outstanding aggregate principal balance of the Swing Line Advances. The Administrative Agent shall notify each such Lender of the amount of such Revolving Advance or participation, and such Lender will transfer to the Administrative Agent for the account of the Swing Line Lender on the next Business Day following such notice, in immediately available funds, the amount of such Revolving Advance or participation.

(iii) If any such Lender shall not have so made its Revolving Advance or its percentage participation available to the Administrative Agent pursuant to this Section 2.3, such Lender agrees to pay interest thereon for each day from such date until the date such amount is paid at the lesser of (A) the Federal Funds Rate for such day for the first three days and thereafter the interest rate applicable to the Revolving Advance and (B) the Maximum Rate. Whenever, at any time after the Administrative Agent has received from any Lender such Lender’s Revolving

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Advance or participating interest in a Swing Line Advance, the Administrative Agent receives any payment on account thereof, the Administrative Agent will pay to such Lender its participating interest in such amount (appropriately adjusted, in the case of interest payments, to reflect the period of time during which such Lender’s Revolving Advance or participating interest was outstanding and funded), which payment shall be subject to repayment by such Lender if such payment received by the Administrative Agent is required to be returned. Each Lender’s obligation to make the Revolving Advance or purchase such participating interests pursuant to this Section 2.3 shall be absolute and unconditional and shall not be affected by any circumstance, including (1) any set-off, counterclaim, recoupment, defense or other right which such Lender or any other Person may have against the Swing Line Lender, the Administrative Agent or any other Person for any reason whatsoever; (2) the occurrence or continuance of a Default or the termination of the Revolving Commitments; (3) any breach of this Agreement by the Borrower or any other Lender; or (4) any other circumstance, happening or event whatsoever, whether or not similar to any of the foregoing. Each Swing Line Advance, once so participated by any Lender, shall cease to be a Swing Line Advance with respect to that amount for purposes of this Agreement, but shall continue to be a Revolving Loan.

(d) Method of Borrowing . If an AutoBorrow Agreement is in effect, each Swing Line Borrowing shall be made as provided in such AutoBorrow Agreement. Otherwise, and except as provided in the clause (c) above, each request for a Swing Line Advance shall be made pursuant to telephone notice to the Swing Line Lender given no later than 1:00 p.m. (Houston, Texas time) on the date of the proposed Swing Line Advance, promptly confirmed by a completed and executed Notice of Borrowing telecopied or facsimiled to the Administrative Agent and the Swing Line Lender. The Swing Line Lender will promptly make the Swing Line Advance available to the Borrower at the Borrower’s account with the Administrative Agent.

(e) Interest for Account of Swing Line Lender . Swing Line Lender shall be responsible for invoicing the Borrower for interest on the Swing Line Advances ( provided that any failure of the Swing Line Lender to provide such invoice shall not release the Borrower from its obligation to pay such interest). Until each Lender funds its Revolving Advance or risk participation pursuant to clause (c) above, interest in respect of Lender’s Revolving Pro Rata Share of the Swing Line Advances shall be solely for the account of the Swing Line Lender.

(f) Payments Directly to Swing Line Lenders . The Borrower shall make all payments of principal and interest in respect of the Swing Line Advances directly to the Swing Line Lender.

(g) Discretionary Nature of the Swing Line Facility . Notwithstanding any terms to the contrary contained herein or in any AutoBorrow Agreement, the Swing Line facility provided herein or in any AutoBorrow Agreement (i) is an uncommitted facility and the Swing Line Lender may, but shall not be obligated to, make Swing Line Advances, and (ii) may be terminated at any time by the Swing Line Lender upon written notice to the Borrower.

Section 2.4 Advances .

(a) Notice . Each Revolving Borrowing, shall be made pursuant to a Notice of Borrowing given not later than (i) 11:00 a.m. (Houston, Texas time) on the third Business Day before the date of the proposed Borrowing, in the case of a LIBOR Advance or (ii) 11:00 a.m. (Houston, Texas time) on the Business Day before the date of the proposed Borrowing, in the case of a Base Rate Advance, by the Borrower to the Administrative Agent, which shall give to each Lender prompt notice of such proposed Borrowing by facsimile or telex. Each Notice of Borrowing shall be by facsimile or telex, confirmed promptly by the Borrower with a hard copy (other than with respect to notice sent by facsimile),

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specifying the requested (i) date of such Borrowing, (ii) Type and Class of Advances comprising such Borrowing, (iii) aggregate amount of such Borrowing, and (iv) if such Borrowing is to be comprised of LIBOR Advances, Interest Period for each such Advance. In the case of a proposed Borrowing comprised of LIBOR Advances, the Administrative Agent shall promptly notify each Lender of the applicable interest rate under Section 2.8(b). Each Lender shall, before 12:00 noon (Houston, Texas time) on the date of such Borrowing, make available for the account of its applicable Lending Office to the Administrative Agent at its address referred to in Section 9.9, or such other location as the Administrative Agent may specify by notice to the Lenders, in same day funds, such Lender’s Revolving Pro Rata Share of such Borrowing. After the Administrative Agent’s receipt of such funds and upon fulfillment of the applicable conditions set forth in Article 3, the Administrative Agent will make such funds available to the Borrower at its account with the Administrative Agent or as otherwise directed by the Borrower with written notice to the Administrative Agent.

(b) Conversions and Continuations . In order to elect to Convert or continue a Revolving Advance under this paragraph, the Borrower shall deliver an irrevocable Notice of Continuation or Conversion to the Administrative Agent at the Administrative Agent’s office no later than 11:00 a.m. (Houston, Texas time) (i) on the Business Day before the date of the proposed conversion date in the case of a Conversion to a Base Rate Advance and (ii) at least three Business Days in advance of the proposed Conversion or continuation date in the case of a Conversion to, or a continuation of, a LIBOR Advance. Each such Notice of Conversion or Continuation shall be in writing or by telex or facsimile confirmed promptly by the Borrower with a hard copy (other than with respect to notice sent by facsimile), specifying (i) the requested Conversion or continuation date (which shall be a Business Day), (ii) the amount, Type, and Class of the Advance to be Converted or continued, (iii) whether a Conversion or continuation is requested and, if a Conversion, into what Type of Advance, and (iv) in the case of a Conversion to, or a continuation of, a LIBOR Advance, the requested Interest Period. Promptly after receipt of a Notice of Conversion or Continuation under this paragraph, the Administrative Agent shall provide each Lender with a copy thereof and, in the case of a Conversion to or a Continuation of a LIBOR Advance, notify each Lender of the applicable interest rate under Section 2.8(b). The portion of Advances comprising part of the same Borrowing that are converted to Advances of another Type shall constitute a new Borrowing.

(c) Certain Limitations . Notwithstanding anything in paragraphs (a) and (b) above:

(i) at no time shall there be more than five Interest Periods applicable to outstanding LIBOR Advances;

(ii) the Borrower may not select LIBOR Advances for any Borrowing at any time when a Default has occurred and is continuing;

(iii) if any Lender shall, at least one Business Day before the date of any requested Borrowing, notify the Administrative Agent that the introduction of or any change in or in the interpretation of any law or regulation makes it unlawful, or that any central bank or other governmental authority asserts that it is unlawful, for such Lender or its applicable Lending Office to perform its obligations under this Agreement to make LIBOR Advances or to fund or maintain LIBOR Advances, (A) the obligation of such Lender to make such LIBOR Advance as part of the requested Borrowing or for any subsequent Borrowing shall be suspended until such Lender shall notify the Borrower that the circumstances causing such suspension no longer exist and such Lender’s portion of such requested Borrowing or any subsequent Borrowing of LIBOR Advances shall be made in the form of a Base Rate Advance, and (B) such Lender agrees to use commercially reasonable efforts (consistent with its internal policies and legal and regulatory restrictions) to designate a different Lending Office if the making of such designation would avoid the effect of this paragraph and would not, in the reasonable judgment of such Lender, be otherwise disadvantageous to such Lender;

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(iv) if the Administrative Agent is unable to determine the LIBO Rate for LIBOR Advances comprising any requested Borrowing, the right of the Borrower to select LIBOR Advances for such Borrowing or for any subsequent Borrowing shall be suspended until the Administrative Agent shall notify the Borrower and the Lenders that the circumstances causing such suspension no longer exist, and each Advance comprising such Borrowing shall be a Base Rate Advance;

(v) if the Majority Lenders shall, at least one Business Day before the date of any requested Borrowing, notify the Administrative Agent that the LIBO Rate for LIBOR Advances comprising such Borrowing will not adequately reflect the cost to such Lenders of making or funding their respective LIBOR Advances, as the case may be, for such Borrowing, the right of the Borrower to select LIBOR Advances for such Borrowing or for any subsequent Borrowing shall be suspended until the Administrative Agent shall notify the Borrower and the Lenders that the circumstances causing such suspension no longer exist, and each Advance comprising such Borrowing shall be a Base Rate Advance; and

(vi) if the Borrower shall fail to select the duration or continuation of any Interest Period for any LIBOR Advances in accordance with the provisions contained in the definition of Interest Period in Section 1.1 and paragraph (b) above, the Administrative Agent will forthwith so notify the Borrower and the Lenders and such Advances will be made available to the Borrower on the date of such Borrowing as Base Rate Advances or, if an existing Advance, Convert into Base Rate Advances.

(d) Notices Irrevocable . Each Notice of Borrowing and Notice of Continuation or Conversion delivered by the Borrower hereunder, including its deemed request for borrowing made under Section 2.2(c), shall be irrevocable and binding on the Borrower.

(e) Administrative Agent Reliance . Unless the Administrative Agent shall have received notice from a Lender before the date of any Revolving Borrowing that such Lender will not make available to the Administrative Agent such Lender’s applicable pro rata share of any Borrowing, the Administrative Agent may assume that such Lender has made its applicable pro rata share of such Borrowing available to the Administrative Agent on the date of such Borrowing in accordance with Section 2.4(a), and the Administrative Agent may, in reliance upon such assumption, make available to the Borrower on such date a corresponding amount. If and to the extent that such Lender shall not have so made its applicable pro rata share of such Borrowing available to the Administrative Agent, such Lender and the Borrower severally agree to immediately repay to the Administrative Agent on demand such corresponding amount, together with interest on such amount, for each day from the date such amount is made available to the Borrower until the date such amount is repaid to the Administrative Agent, at (i) in the case of the Borrower, the interest rate applicable on such day to Advances comprising such Borrowing and (ii) in the case of such Lender, the lesser of (A) the Federal Funds Rate for such day and (B) the Maximum Rate. If such Lender shall repay to the Administrative Agent such corresponding amount and interest as provided above, such corresponding amount so repaid shall constitute such Lender’s Advance as part of such Borrowing for purposes of this Agreement even though not made on the same day as the other Advances comprising such Borrowing.

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Section 2.5 Prepayments .

(a) Right to Prepay . The Borrower shall have no right to prepay any principal amount of any Advance except as provided in this Section 2.5.

(b) Optional . The Borrower may elect to prepay any of the Advances without penalty or premium except as set forth in Section 2.10 and after giving by 11:00 a.m. (Houston, Texas time) (i) in the case of LIBOR Advances, at least three Business Days’ or (ii) in case of Base Rate Advances, one Business Day’s prior written notice to the Administrative Agent stating the proposed date and aggregate principal amount of such prepayment. If any such notice is given, the Borrower shall prepay Advances comprising part of the same Borrowing in whole or ratably in part in an aggregate principal amount equal to the amount specified in such notice, together with accrued interest to the date of such prepayment on the principal amount prepaid and amounts, if any, required to be paid pursuant to Section 2.10 as a result of such prepayment being made on such date; provided that (A) each optional prepayment of LIBOR Advances shall be in a minimum amount not less than $200,000 and in multiple integrals of $100,000 in excess thereof, (B) each optional prepayment of Base Rate Advances shall be in a minimum amount not less than $100,000 and in multiple integrals of $100,000 in excess thereof and (C) each optional prepayment of Swing Line Advances shall have no minimum requirement. If an AutoBorrow Agreement is in effect, each prepayment of Swing Line Advances shall be made as provided in such AutoBorrow Agreement.

(c) Interest; Costs . Each prepayment pursuant to this Section 2.5 shall be accompanied by accrued interest on the amount prepaid to the date of such prepayment and amounts, if any, required to be paid pursuant to Section 2.10 as a result of such prepayment being made on such date.

Section 2.6 Repayment .

(a) Revolving Advances . The Borrower shall pay to the Administrative Agent for the ratable benefit of each Lender the aggregate outstanding principal amount of the Revolving Advances on the Maturity Date.

(b) Swing Line Advances . Each Swing Line Advance shall be paid in full on the Swing Line Payment Date.

Section 2.7 Fees .

(a) Commitment Fees . The Borrower agrees to pay to the Administrative Agent for the account of each Lender a Commitment Fee on the average daily amount by which (i) such Lender’s Revolving Commitment exceeds (ii) the sum of such Lender’s outstanding Revolving Advances plus such Lender’s Revolving Pro Rata Share of the Letter of Credit Exposure, at the rate equal to the Applicable Margin for Commitment Fees for such period; provided that, no Commitment Fee shall accrue on the Revolving Commitment of a Defaulting Lender during the period such Lender remains a Defaulting Lender. The Commitment Fee is due quarterly in arrears on March 31, June 30, September 30, and December 31 of each year commencing on March 31, 2010, and on the Maturity Date. For purposes of this Section 2.7(a) only, amounts advanced under the Swing Line Note shall not reduce the amount of the unused Revolving Commitment.

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(b) Fees for Letters of Credit . The Borrower agrees to pay the following:

(i) To the Administrative Agent for the pro rata benefit of the Lenders a per annum letter of credit fee for each Letter of Credit issued hereunder, for the period such Letter of Credit is to be outstanding, in an amount equal to the greater of (A) the Applicable Margin for LIBOR Advances per annum on the face amount of such Letter of Credit, and (B) $600 per Letter of Credit. Such fee shall be due and payable quarterly in arrears on March 31, June 30, September 30, and December 31 of each year, and on the Maturity Date.

(ii) To the Issuing Lender, a fronting fee for each Letter of Credit equal to the greater of (A) 0.250% per annum on the face amount of such Letter of Credit and (B) $600. Such fee shall be due and payable in advance on the date of the issuance of the Letter of Credit, and, in the case of an increase or extension only, on the date of such increase or such extension.

(iii) To the Administrative Agent for the pro rata benefit of the Lenders such additional per annum letter of credit fee for each commercial Letter of Credit issued hereunder, for the period such Letter of Credit is to be outstanding, in an amount agreed to between the Borrower and the Issuing Lender in writing. Such fee shall be due and payable quarterly in arrears on March 31, June 30, September 30, and December 31 of each year, and on the Maturity Date.

(iv) To the Issuing Lender, an additional fronting fee for each commercial Letter of Credit equal an amount agreed to between the Borrower and the Issuing Lender. Such fee shall be due and payable in advance on the date of the issuance of the Letter of Credit in writing, and, in the case of an increase or extension only, on the date of such increase or such extension.

(v) To the Issuing Lender such other usual and customary fees associated with any transfers, amendments, drawings, negotiations or reissuances of any Letters of Credit. Such fees shall be due and payable as requested by the Issuing Lender in accordance with the Issuing Lender’s then current fee policy.

The Borrower shall have no right to any refund of letter of credit fees previously paid by the Borrower, including any refund claimed because any Letter of Credit is canceled prior to its expiration date.

(c) Other Fee . The Borrower agrees to pay the fees to the Administrative Agent as set forth in the Fee Letter.

Section 2.8 Interest .

(a) Base Rate Advances . Each Base Rate Advance shall bear interest at the Adjusted Base Rate in effect from time to time plus the Applicable Margin for Base Rate Advances for such period, provided that while an Event of Default is continuing the Base Rate Advances shall bear interest at the Adjusted Base Rate in effect from time to time plus the Applicable Margin plus 2%. The Borrower shall pay to Administrative Agent for the ratable account of each Lender all accrued but unpaid interest on such Lender’s Base Rate Advances on each March 31, June 30, September 30, and December 31 commencing on March 31, 2010, and on the Maturity Date. The Swing Line Advances shall bear interest only at the Adjusted Base Rate plus the Applicable Margin for Base Rate Advances or such other per annum rate to be agreed to between the Borrower and the Swing Line Lender; provided that while an Event of Default is continuing the Swing Line Advances shall bear interest at the Adjusted Base Rate in effect from time to time plus the Applicable Margin for Base Rate Advances plus 2%.

(b) LIBOR Advances . Each LIBOR Advance shall bear interest during its Interest Period equal to at all times the LIBO Rate for such Interest Period plus the Applicable Margin for LIBOR

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Advances for such period; provided that while an Event of Default is continuing, each LIBOR Advance shall bear interest at the LIBO Rate in effect from time to time plus the Applicable Margin plus 2%. The Borrower shall pay to the Administrative Agent for the ratable account of each Lender all accrued but unpaid interest on each of such Lender’s LIBOR Advances on the last day of the Interest Period therefor (provided that for LIBOR Advances with six month Interest Periods, accrued but unpaid interest shall also be due on the day three months from the first day of such Interest Period), on the date any LIBOR Advance is repaid, and on the Maturity Date.

(c) Retroactive Adjustments of Applicable Margin . In the event that any financial statement or Compliance Certificate delivered pursuant to Section 5.2 is shown to be inaccurate (regardless of whether this Agreement or the Revolving Commitments are in effect when such inaccuracy is discovered), and such inaccuracy, if corrected, would have led to the application of a higher Applicable Margin for any period (an “ Applicable Period ”) than the Applicable Margin applied for such Applicable Period, then (i) the Borrower shall immediately deliver to the Administrative Agent a corrected Compliance Certificate for such Applicable Period, (ii) the Applicable Margin shall be determined as if the higher Applicable Margin that would have applied were applicable for such Applicable Period (and in any event at Level III if the inaccuracy was the result of dishonesty, fraud or willful misconduct), and (iii) the Borrower shall immediately, without further action by the Administrative Agent, any Lender or the Issuing Lender, pay to the Administrative Agent for the account of the applicable Lenders, the accrued additional interest owing as a result of such increased Applicable Margin for such Applicable Period. This Section 2.8(c) shall not limit the rights of the Administrative Agent and Lenders with respect to the default rate of interest as set forth in Section 2.8(a) and Section 2.8(b) and Article 7. The Borrower’s obligations under this Section 2.8(c) shall survive the termination of the Revolving Commitments and the repayment of all other Obligations hereunder.

Section 2.9 Illegality . If any Lender shall notify the Borrower that the introduction of or any change in or in the interpretation of any law or regulation makes it unlawful, or that any central bank or other governmental authority asserts that it is unlawful, for such Lender or its applicable Lending Office to perform its obligations under this Agreement to make, maintain, or fund any LIBOR Advances of such Lender then outstanding hereunder, (a) the Borrower shall, no later than 11:00 a.m. (Houston, Texas, time) (i) if not prohibited by law, on the last day of the Interest Period for each outstanding LIBOR Advance or (ii) if required by such notice, on the second Business Day following its receipt of such notice, prepay all of the LIBOR Advances of such Lender then outstanding, together with accrued interest on the principal amount prepaid to the date of such prepayment and amounts, if any, required to be paid pursuant to Section 2.10 as a result of such prepayment being made on such date, (b) such Lender shall simultaneously make a Base Rate Advance to the Borrower on such date in an amount equal to the aggregate principal amount of the LIBOR Advances prepaid to such Lender, and (c) the right of the Borrower to select LIBOR Advances from such Lender for any subsequent Borrowing shall be suspended until such Lender shall notify the Borrower that the circumstances causing such suspension no longer exist. Each Lender agrees to use commercially reasonable efforts (consistent with its internal policies and legal and regulatory restrictions) to designate a different Lending Office if the making of such designation would avoid the effect of this paragraph and would not, in the reasonable judgment of such Lender, be otherwise disadvantageous to such Lender.

Section 2.10 Breakage Costs . Upon demand of any Lender (with a copy to the Administrative Agent) from time to time, the Borrower shall promptly compensate such Lender for and hold such Lender harmless from any loss, cost or expense incurred by it as a result of:

(a) any continuation, conversion, payment or prepayment (including any deemed payment or repayment and any reallocated repayment to non-defaulting Lenders provided for in Section 2.12(a)) of any Advance other than a Base Rate Advance on a day other than the last day of the Interest Period for such Advance (whether voluntary, mandatory, automatic, by reason of acceleration, or otherwise);

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(b) any failure by the Borrower (for a reason other than the failure of such Lender to make an Advance) to prepay, borrow, continue or convert any Advance other than a Base Rate Advance on the date or in the amount notified by the Borrower; or

(c) any assignment of an LIBO Rate Advance on a day other than the last day of the Interest Period therefor as a result of a request by the Borrower pursuant to Section 2.14;

including any loss of anticipated profits, any foreign exchange losses and any loss or expense arising from the liquidation or reemployment of funds obtained by it to maintain such Advance, from fees payable to terminate the deposits from which such funds were obtained or from the performance of any foreign exchange contract. The Borrower shall also pay any customary administrative fees charged by such Lender in connection with the foregoing. For purposes of calculating amounts payable by the Borrower to the Lenders under this Section 2.10, the requesting Lender shall be deemed to have funded the LIBO Rate Advances made by it at the LIBO Base Rate used in determining the LIBO Rate for such Advance by a matching deposit or other borrowing in the offshore interbank market for Dollars for a comparable amount and for a comparable period, whether or not such LIBO Rate Advance was in fact so funded.

Section 2.11 Increased Costs .

(a) LIBOR Advances . If any Change in Law shall:

(i) impose, modify, or deem applicable any reserve, special deposit, assessment, or similar requirement (other than by way of imposition or increase of reserve requirements included in the LIBO Rate Reserve Percentage) relating to any extensions of credit or other assets of, or any deposits with or other liabilities or commitments of, financial institutions generally, including such Lender (or its applicable Lending Office), including the Revolving Commitments of such Lender hereunder; or

(ii) impose on financial institutions generally, including such Lender (or its applicable Lending Office), or on the London interbank market any other condition affecting this Agreement or its Notes or any of such extensions of credit or liabilities or commitments;

and the result of any of the foregoing is to increase the cost to such Lender (or its applicable Lending Office) of making, Converting into, continuing, or maintaining any LIBOR Advances or to reduce any sum received or receivable by such Lender (or its applicable Lending Office) under this Agreement or its Notes with respect to any LIBOR Advances, then the Borrower shall pay to such Lender within three Business Days after written demand made by such Lender such amount or amounts as such Lender determines in good faith to be necessary to compensate such Lender for such increased cost or reduction.

(b) Capital Adequacy . If, after the Effective Date, any Lender or the Issuing Lender shall have determined that any Change in Law affecting such Lender or Issuing Lender or any lending office of such Lender or such Lender’s or Issuing Lender’s holding company, if any, regarding capital requirements has or would have the effect of reducing the rate of return on the capital of financial institutions generally, including such Lender or the Issuing Lender or any corporation controlling such Lender or the Issuing Lender, as a consequence of such Lender’s or the Issuing Lender’s obligations hereunder to a level below that which such Lender or the Issuing Lender or such corporation could have achieved but for such Change in Law (taking into consideration its policies with respect to capital adequacy), then from time to time within three Business Days after written demand by such Lender or the

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Issuing Lender, as the case may be, the Borrower shall pay to such Lender or the Issuing Lender such additional amount or amounts as such Lender determines in good faith to be necessary to compensate such Lender or the Issuing Lender for such reduction.

(c) Mitigation . Each Lender shall promptly notify the Borrower and the Administrative Agent of any event of which it has knowledge, occurring after the Effective Date, which will entitle such Lender to compensation pursuant to this Section 2.11 and will designate a different Lending Office if such designation will avoid the need for, or reduce the amount of, such compensation and will not, in the reasonable judgment of such Lender, be otherwise disadvantageous to it. Any Lender claiming compensation under this Section 2.11 shall furnish to the Borrower and the Administrative Agent a statement setting forth the additional amount or amounts to be paid to it hereunder which shall be determined by such Lender in good faith and which shall be conclusive in the absence of manifest error. In determining such amount, such Lender may use any reasonable averaging and attribution methods.

(d) Delay in Requests . Failure or delay on the part of any Lender or Issuing Lender to demand compensation pursuant to this Section 2.11 shall not constitute a waiver of such Lender’s or such Issuing Lender’s right to demand such compensation, provided that the Borrower shall not be required to compensate a Lender or Issuing Lender pursuant to this Section 2.11 for any increased costs incurred or reductions suffered more than one year prior to the date that such Lender or Issuing Lender, as the case may be, notifies the Borrower and the Administrative Agent of the Change in Law giving rise to such increased costs or reductions and of such Lender’s or Issuing Lender’s intention to claim compensation therefor (except that, if the Change in Law giving rise to such increased costs or reductions is retroactive, then the one-year period referred to above shall be extended to include the period of retroactive effect thereof).

Section 2.12 Payments and Computations .

(a) Payments . All payments of principal, interest, and other amounts to be made by the Borrower under this Agreement and other Credit Documents shall be made to the Administrative Agent in Dollars and in immediately available funds, without setoff, deduction, or counterclaim; provided that, the Borrower may setoff amounts owing to any Lender that is at such time a Defaulting Lender against Advances that such Defaulting Lender failed to the fund to the Borrower under this Agreement (the “ Unfunded Advances ”) so long as (i) the Borrower shall have delivered prior written notice of such setoff to the Administrative Agent and such Defaulting Lender, (ii) the Advances made by the non-defaulting Lenders as part of the original Borrowing to which the Unfunded Advances applied shall still be outstanding, (iii) if such Defaulting Lender failed to fund Advances under more than one Borrowing, such setoff shall be applied in a manner satisfactory to the Administrative Agent, and (iv) upon the application of such setoff, the Unfunded Advances shall be deemed to have been made by such Defaulting Lender on the effective date of such setoff.

(b) Payment Procedures . The Borrower shall make each payment under this Agreement and under the Notes not later than 11:00 a.m. (Houston, Texas time) on the day when due in Dollars to the Administrative Agent at the location referred to in the Notes (or such other location as the Administrative Agent shall designate in writing to the Borrower) in same day funds. The Administrative Agent will promptly thereafter, and in any event prior to the close of business on the day any timely payment is made, cause to be distributed like funds relating to the payment of principal, interest or fees ratably (other than amounts payable solely to the Administrative Agent or a specific Lender pursuant to Sections 2.9, 2.10, 2.11, 2.13, 2.14, and 9.2 but after taking into account payments effected pursuant to Section 9.1) in accordance with each Lender’s applicable pro rata share to the Lenders for the account of their respective applicable Lending Offices, and like funds relating to the payment of any other amount payable to any Lender to such Lender for the account of its applicable Lending Office, in each case to be applied in

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accordance with the terms of this Agreement. Upon receipt of other amounts due solely to the Administrative Agent, the Issuing Lender, the Swing Line Lender, or a specific Lender, the Administrative Agent shall distribute such amounts to the appropriate party to be applied in accordance with the terms of this Agreement.

(c) Non-Business Day Payments . Whenever any payment shall be stated to be due on a day other than a Business Day, such payment shall be made on the next succeeding Business Day, and such extension of time shall in such case be included in the computation of payment of interest or fees, as the case may be; provided that if such extension would cause payment of interest on or principal of LIBOR Advances to be made in the next following calendar month, such payment shall be made on the next preceding Business Day.

(d) Computations . All computations of interest for Base Rate Advances shall be made by the Administrative Agent on the basis of a year of 365/366 days (other than based on the Daily One-Month LIBOR) and all computations of all other interest and fees shall be made by the Administrative agent on the basis of a year of 360 days, in each case for the actual number of days (including the first day, but excluding the last day) occurring in the period for which such interest or fees are payable. Each determination by the Administrative Agent of an amount of interest or fees shall be conclusive and binding for all purposes, absent manifest error.

(e) Sharing of Payments, Etc . If any Lender shall obtain any payment (whether voluntary, involuntary, through the exercise of any right of set-off, or otherwise) on account of the Advances made by it in excess of its ratable share of payments on account of the Advances or Letter of Credit Obligations obtained by the Lenders (other than as a result of a termination of a Defaulting Lender’s Revolving Commitment under Section 2.1(b)(ii), the setoff right of the Borrower under clause (a) above, or the non-pro rata application of payments provided in the last sentence of this clause (e)), such Lender shall notify the other Lenders and forthwith purchase from the other Lenders such participations in the Advances made by it or the Letter of Credit Obligations held by it as shall be necessary to cause such purchasing Lender to share the excess payment ratably with the other Lenders; provided that if all or any portion of such excess payment is thereafter recovered from such purchasing Lender, such purchase from the other Lenders shall be rescinded and each such Lender shall repay to the purchasing Lender the purchase price to the extent of such Lender’s ratable share, but without interest. The Borrower agrees that any Lender so purchasing a participation from another Lender pursuant to this Section 2.12(e) may, to the fullest extent permitted by law, exercise all its rights of payment (including the right of set-off) with respect to such participation as fully as if such Lender were the direct creditor of the Borrower in the amount of such participation. If a Lender fails to fund a Revolving Advance with respect to a Borrowing as and when required hereunder and the Borrower subsequently makes a repayment of any Revolving Advances, then, after taking into account any setoffs made pursuant to Section 2.12(a) above, such payment shall be applied among the non-defaulting Lenders ratably in accordance with their respective Revolving Commitment percentages until each Lender (including any Lender that is at such time a Defaulting Lender) has its percentage of all of the outstanding Revolving Advances and the balance of such repayment shall be applied among the Lenders in accordance with their Revolving Pro Rata Share.

Section 2.13 Taxes .

(a) No Deduction for Certain Taxes . Any and all payments by any Credit Party under any of the Credit Documents to the Administrative Agent, the Issuing Lender, or a Lender shall be made, in accordance with Section 2.12, free and clear of and without deduction for any and all present or future taxes, levies, imposts, deductions, charges, or withholdings, and all liabilities with respect thereto, excluding, in the case of the Administrative Agent, the Issuing Lender, or a Lender, (i) taxes imposed on its income and franchise (or margin) taxes imposed on it by the jurisdiction (or any political subdivision

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thereof) under (A) the laws of which (or under the laws of a political subdivision of which) the Administrative Agent, the Issuing Lender, or such Lender is organized or in which its principal executive office is located, (B) in the case of each Lender, the laws of which (or under the laws of a political subdivision of which) such Lender’s applicable Lending Office is located, and (C) the laws of the State of Texas; and (ii) any taxes imposed by the United States of America by means of withholding at the source, if and to the extent such United States withholding taxes are in effect on the date a Lender becomes a Lender hereunder (all such nonexcluded taxes, levies, imposts, deductions, charges, withholdings, and liabilities being hereinafter referred to as “ Taxes ”). Except as provided in Section 2.13(f), if the Borrower shall be required by law to deduct any Taxes from or in respect of any sum payable to the Administrative Agent, the Issuing Lender, or any Lender, (i) the sum payable shall be increased as may be necessary so that, after making all required deductions (including deductions applicable to additional sums payable under this Section 2.13), such Lender receives an amount equal to the sum it would have received had no such deductions been made; (ii) the Borrower shall make such deductions; and (iii) the Borrower shall pay the full amount deducted to the relevant Governmental Authority or other authority in accordance with applicable law.

(b) Other Taxes . In addition, except as provided in Section 2.13(f), the Borrower agrees to pay any present or future stamp or documentary taxes or any other excise or property taxes, charges, or similar levies which arise from any payment made under any Credit Document or from the execution, delivery, or registration of, or otherwise with respect to, this Agreement, the Notes, or the other Credit Documents (hereinafter referred to as “Other Taxes”).

(c) Indemnification . EXCEPT AS PROVIDED IN SECTION 2.13(F), THE BORROWER INDEMNIFIES EACH LENDER, THE ISSUING LENDER, AND THE ADMINISTRATIVE AGENT FOR THE FULL AMOUNT OF TAXES OR OTHER TAXES (INCLUDING, WITHOUT LIMITATION, ANY TAXES OR OTHER TAXES IMPOSED ON AMOUNTS PAYABLE UNDER THIS SECTION 2.13) PAID BY SUCH LENDER, THE ISSUING LENDER, OR THE ADMINISTRATIVE AGENT (AS THE CASE MAY BE) AND ANY LIABILITY (INCLUDING INTEREST AND EXPENSES) ARISING THEREFROM OR WITH RESPECT THERETO, WHETHER OR NOT SUCH TAXES OR OTHER TAXES WERE CORRECTLY OR LEGALLY ASSERTED.

(d) Evidence of Tax Payments . As soon as practicable after any payment of Taxes or Other Taxes by any Credit Party to a Governmental Authority, the Borrower shall deliver to the Administrative Agent the original or a certified copy of any receipt issued by such Governmental Authority evidencing such payment.

(e) Foreign Lender Withholding Exemption . Each Lender that is not incorporated under the laws of the United States of America or a state thereof and that is entitled to an exemption from United States withholding tax with respect to payments under this Agreement under applicable law or any treaty to which the United States is a party shall deliver to the Borrower (with a copy to the Administrative Agent), at the time or times prescribed by applicable law, such properly completed and executed documentation (including Internal Revenue Service Forms W-8BEN or W-8ECI) prescribed by applicable law or reasonably requested by the Borrower as will permit such payments to be made without withholding.

(f) Failure to Provide Forms . For any period with respect to which a Lender has failed to provide the Borrower or the Administrative Agent with the appropriate forms referred to in this Section 2.13 (unless such failure is due to a change in treaty, law or regulation occurring after the date on which such Lender becomes a Lender hereunder), such Lender shall not be entitled to indemnification or payment under Section 2.13(a), (b), or (c) with respect to Taxes imposed by the United States; provided that if a Lender, that is otherwise exempt from or subject to a reduced rate of withholding tax, becomes

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subject to Taxes because of its failure to deliver a form required hereunder, the Borrower shall take such steps as such Lender shall reasonably request, and at the expenses of such Lender, to assist such Lender to recover such Taxes.

(g) Mitigation . Each Lender shall use reasonable efforts (consistent with its internal policies and legal and regulatory restrictions) to select a jurisdiction for its applicable Lending Office or change the jurisdiction of its applicable Lending Office, as the case may be, so as to avoid the imposition of any Taxes or Other Taxes or to eliminate or reduce the payment of any additional sums under this Section 2.13; provided, that no such selection or change of jurisdiction for its applicable Lending Office shall be made if, in the reasonable judgment of such Lender, such selection or change would be disadvantageous to such Lender.

(h) Tax Credits and Refunds . If the Administrative Agent, any Lender or the Issuing Lender determines, in its sole discretion, that it has received a refund of any Taxes or Other Taxes as to which it has been indemnified by the Borrower or with respect to which the Borrower has paid additional amounts pursuant to this Section, it shall pay to the Borrower an amount equal to such refund (but only to the extent of indemnity payments made, or additional amounts paid, by the Borrower under this Section with respect to the Taxes or Other Taxes giving rise to such refund), net of all out-of-pocket expenses of the Administrative Agent, such Lender or the Issuing Lender, as the case may be, and without interest (other than any interest paid by the relevant Governmental Authority with respect to such refund), provided that the Borrower, upon the request of the Administrative Agent, such Lender or the Issuing Lender, agrees to repay the amount paid over to the Borrower (plus any penalties, interest or other charges imposed by the relevant Governmental Authority) to the Administrative Agent, such Lender or the Issuing Lender in the event the Administrative Agent, such Lender or the Issuing Lender is required to repay such refund to such Governmental Authority. This subsection shall not be construed to require the Administrative Agent, any Lender or the Issuing Lender to make available its tax returns (or any other information relating to its taxes that it deems confidential) to any Borrower or any other Person.

(i) Payment . If the Administrative Agent or any Lender becomes entitled to receive payment of Taxes, Other Taxes or additional sums pursuant to this Section 2.13, it shall give notice and demand thereof to the Borrower, and the Borrower (unless the Administrative Agent or Lender shall withdraw such notice and demand or the Borrower is not obligated to pay such amounts) shall pay such Taxes, Other Taxes or additional sums within 30 days after the Borrower’s receipt of such notice and demand.

Section 2.14 Replacement of Lenders . If (a) the Borrower is required pursuant to Section 2.11 or 2.13 to make any additional payment to any Lender, (b) any Lender’s obligation to make or continue, or to convert Base Rate Advances into, LIBOR Advances shall be suspended pursuant to 2.4(c)(iii) or 2.9, or (c) any Lender is a Defaulting Lender or a Potential Defaulting Lender (any such Lender described in any of the preceding clauses (a) – (c), being a “ Subject Lender ”), then (i) in the case of a Defaulting Lender or a Potential Defaulting Lender, the Administrative Agent may, upon notice to the Subject Lender and the Borrower, require such Subject Lender to assign and delegate, without recourse (in accordance with and subject to the restrictions contained in, and consents required by, Section 9.7), all of its interests, rights and obligations under this Agreement and the related Credit Documents as a Lender to an Eligible Assignee that shall assume such obligations (which assignee may be another Lender, if a Lender accepts such assignment) and (ii) in the case of any Subject Lender, including a Potential Defaulting Lender, the Borrower may, upon notice to the Subject Lender and the Administrative Agent and at the Borrower’s sole cost and expense, require such Subject Lender to assign and delegate, without recourse (in accordance with and subject to the restrictions contained in, and consents required by, Section 9.7), all of its interests, rights and obligations under this Agreement and the related Credit Documents to an Eligible Assignee that shall assume such obligations (which assignee may be another Lender, if a Lender accepts such assignment), provided that, in any event

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(A) as to assignments requested by the Borrower, the Borrower shall have paid to the Administrative Agent the assignment fee specified in Section 9.7;

(B) such Subject Lender shall have received payment of an amount equal to the outstanding principal of its applicable Advances and participations in outstanding Letter of Credit Obligations, accrued interest thereon, accrued fees and all other amounts payable to it hereunder and under the other Credit Documents (including any amounts under Section 2.10) from the assignee (to the extent of such outstanding principal and accrued interest and fees) or the Borrower (in the case of all other amounts);

(C) in the case of any such assignment resulting from a claim for compensation under Section 2.13, such assignment will result in a reduction in such compensation or payments thereafter; and

(D) such assignment does not conflict with applicable Legal Requirements.

A Lender shall not be required to make any such assignment or delegation if, prior thereto, as a result of a waiver by such Lender or otherwise, the circumstances entitling the Borrower to require such assignment and delegation cease to apply. Solely for purposes of effecting any assignment involving a Defaulting Lender under this Section 2.14 and to the extent permitted under applicable Legal Requirements, each Lender hereby designates and appoints the Administrative Agent as true and lawful agent and attorney-in-fact, with full power and authority, for and on behalf of and in the name of such Lender to execute, acknowledge and deliver the Assignment and Acceptance required hereunder if such Lender is a Defaulting Lender and such Lender shall be bound thereby as fully and effectively as if such Lender had personally executed, acknowledged and delivered the same . In lieu of the Borrower or the Administrative Agent replacing a Defaulting Lender as provided in this Section 2.14, the Borrower may terminate such Defaulting Lender’s Revolving Commitment as provided in Section 2.1(b)(ii).

Section 2.15 Defaulting Lender Cure . If the Borrower, the Administrative Agent, and the Issuing Lender agree in writing in their discretion that a Lender that is a Defaulting Lender or a Potential Defaulting Lender should no longer be deemed to be a Defaulting Lender or Potential Defaulting Lender, as the case may be, the Administrative Agent will so notify the parties hereto, whereupon as of the effective date specified in such notice and subject to any conditions set forth therein, such Lender will, to the extent applicable, purchase such portion of outstanding Advances of the other Lenders and/or make such other adjustments as the Administrative Agent may determine to be necessary to cause the Advances and Letter of Credit Exposure of the Lenders to be on a pro rata basis in accordance with their respective Revolving Commitments, whereupon such Lender will cease to be a Defaulting Lender or Potential Defaulting Lender (and the Advances and Letter of Credit Exposure of each Lender will automatically be adjusted on a prospective basis to reflect the foregoing); provided that no adjustments will be made retroactively with respect to fees accrued or payments made by or on behalf of the Borrower while such Lender was a Defaulting Lender; and provided , further, that except to the extent otherwise expressly agreed by the affected parties, no cessation hereunder as being a Defaulting Lender or Potential Defaulting Lender will constitute a waiver or release of any claim of any party hereunder arising from such Lender’s having been a Defaulting Lender or Potential Defaulting Lender.

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ARTICLE 3

CONDITIONS OF EFFECTIVENESS

Section 3.1 Conditions to Effectiveness . This Agreement shall become effective upon satisfaction of the following conditions precedent:

(a) Documentation . The Administrative Agent shall have received the following, duly executed by all the parties thereto, in form and substance reasonably satisfactory to the Administrative Agent and the Lenders:

(i) this Agreement and all attached Exhibits and Schedules and a Note payable to the order of each Lender;

(ii) certificates of insurance in compliance with Section 5.3(b) of this Agreement;

(iii) a certificate from an authorized officer of the Borrower dated as of the Effective Date stating that as of such date (A) all representations and warranties of the Borrower set forth in this Agreement are true and correct and (B) no Default then exists;

(iv) a secretary’s certificate from each Credit Party certifying such Credit Party’s (A) officers’ incumbency, (B) authorizing resolutions, (C) organizational documents, and (D) governmental approvals, if any, with respect to the Credit Documents to which the Borrower is a party;

(v) certificates of good standing for each Credit Party in the state in which each such Person is incorporated or organized, which certificates shall be dated a date not earlier than 30 days prior to the Effective Date;

(vi) a legal opinion of Haynes and Boone, L.L.P. as outside counsel to the Credit Parties, in form and substance reasonably acceptable to the Administrative Agent; and

(vii) such other documents, governmental certificates, agreements, and lien searches as the Administrative Agent or any Lender may reasonably request.

(b) Consents; Authorization; Conflicts . The Borrower shall have received any consents, licenses and approvals required in accordance with applicable law, or in accordance with any document, agreement, instrument or arrangement to which the Borrower, or any Subsidiary is a party, in connection with the execution, delivery, performance, validity and enforceability of this Agreement and the other Credit Documents. In addition, the Borrower and the Subsidiaries shall have all such material consents, licenses and approvals required in connection with the continued operation of the Borrower and the Subsidiaries, and such approvals shall be in full force and effect, and all applicable waiting periods shall have expired without any action being taken or threatened by any competent authority which would restrain, prevent or otherwise impose adverse conditions on this Agreement and the actions contemplated hereby.

(c) Representations and Warranties . The representations and warranties contained in Article 4 and in each other Credit Document shall be true and correct on and as of the Effective Date before and after giving effect to the initial Borrowings or issuance (or deemed issuance) of Letters of Credit and to the application of the proceeds from such Borrowing, as though made on and as of such date.

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(d) Payment of Fees . The Borrower shall have paid the fees and expenses required to be paid as of the Effective Date pursuant to Sections 2.7(c) and 9.1 or any other provision of a Credit Document.

(e) Other Proceedings . No action, suit, investigation or other proceeding (including, without limitation, the enactment or promulgation of a statute or rule) by or before any arbitrator or any Governmental Authority shall be pending or, to the knowledge of Borrower, threatened and no preliminary or permanent injunction or order by a state or federal court shall have been entered (i) in connection with this Agreement, any other Credit Agreement or any transaction contemplated hereby or thereby or (ii) which, in any case, in the judgment of the Administrative Agent, could reasonably be expected to result in a Material Adverse Change.

(f) Other Reports . The Administrative Agent shall have received, in form and substance reasonably satisfactory to it, all environmental reports, and such other reports, audits or certifications as it may reasonably request, which reports the Administrative Agent acknowledges it has received as of the date of this Agreement.

(g) Material Adverse Change . No event or circumstance that could reasonably be expected to result in a material adverse change in the business, condition (financial or otherwise), prospects, or results of operations of the Borrower and its Subsidiaries, taken as a whole, shall have occurred since September 30, 2009.

(h) No Default . No Default then exists.

(i) Solvency . The Administrative Agent shall have received a certificate in form and substance reasonably satisfactory to the Administrative Agent from a senior financial officer of the Borrower and each Guarantor certifying that, before and after giving effect to the initial Borrowings made hereunder on the Effective Date, the Borrower and each such other Guarantor is Solvent (assuming with respect to each Guarantor, that the fraudulent conveyance savings language contained in the Guaranty applicable to such Guarantor will be given full effect).

(j) Delivery of Financial Statements . The Administrative Agent shall have received true and correct copies of (i) the audited financial statements for the fiscal year ended December 31, 2008 and (ii) the unaudited financial statements for the fiscal quarter ended September 30, 2009.

(k) Due Diligence . The Administrative Agent shall have completed its business and legal due diligence and be satisfied with the results thereof.

(l) USA Patriot Act . The Borrower has delivered to each Lender that is subject to the Patriot Act such information requested by such Lender in order to comply with the Patriot Act.

Section 3.2 Conditions Precedent to Each Borrowing and to Each Issuance, Extension or Renewal of a Letter of Credit . The obligation of each Lender to make an Advance on the occasion of each Borrowing (including the initial Borrowing) and the obligation of the Issuing Lender to issue, increase, renew or extend a Letter of Credit (including the deemed issuance of Letters of Credit) shall be subject to the further conditions precedent that on the date of such Borrowing or such issuance, increase, renewal or extension:

(a) Representations and Warranties . As of the date of the making of any Advance or issuance, increase, renewal or extension of any Letter of Credit, the representations and warranties made by any Credit Party or any officer of any Credit Party contained in the Credit Documents shall be true and

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correct in all material respects (except that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof) on such date, except that any representation and warranty which by its terms is made as of a specified date shall be required to be true and correct only as of such specified date and each request for the making of any Advance or issuance, increase, renewal or extension of any Letter of Credit and the making of such Advance or the issuance, increase, renewal or extension of such Letter of Credit shall be deemed to be a reaffirmation of such representations and warranties.

(b) Event of Default . As of the date of the making of any Advance or issuance, increase, renewal or extension of any Letter of Credit, no Default or Event of Default shall exist, and the making of such Advance or issuance, increase, renewal or extension of such Letter of Credit would not cause a Default or Event of Default.

(c) Payment in Full of Existing Debt . Prior to, or concurrently with, the making of the initial Advances hereunder, all outstanding obligations owing under the Existing Debt shall have been paid in full and the Administrative Agent shall have received a “pay-off” letter (or such other evidence) in form and substance reasonably satisfactory to the Administrative Agent with respect to all such Debt evidencing the termination of all commitments to lend under the respective loan documents; and the Administrative Agent shall have received from any Person holding any Lien securing any such Debt, such UCC (or equivalent) termination statements, mortgage releases, releases of assignments of leases and rents, and other instruments, in each case in proper form for recording or filing, as the Administrative Agent shall have reasonably requested to release and terminate of record the Liens securing such Debt.

Section 3.3 Determinations Under Sections 3.1 and 3.2 . For purposes of determining compliance with the conditions specified in Sections 3.1 and 3.2, each Lender shall be deemed to have consented to, approved or accepted or to be satisfied with each document or other matter required thereunder to be consented to or approved by or acceptable or satisfactory to the Lenders unless an officer of the Administrative Agent responsible for the transactions contemplated by the Credit Documents shall have received written notice from such Lender prior to the Borrowings hereunder specifying its objection thereto and such Lender shall not have made available to the Administrative Agent such Lender’s ratable portion of such Borrowings.

ARTICLE 4

REPRESENTATIONS AND WARRANTIES

Each Credit Party hereto represents and warrants as follows:

Section 4.1 Organization . Each Credit Party is duly and validly organized and existing and in good standing under the laws of its jurisdiction of incorporation or formation and is authorized to do business and is in good standing in all jurisdictions in which such qualifications or authorizations are necessary except where the failure to be so qualified or authorized could not reasonably be expected to result in a Material Adverse Change. As of the Effective Date, each Credit Party’s type of organization and jurisdiction of incorporation or formation are set forth on Schedule 4.1.

Section 4.2 Authorization . The execution, delivery, and performance by each Credit Party of each Credit Document to which such Credit Party is a party and the consummation of the transactions contemplated thereby (a) are within such Credit Party’s powers, (b) have been duly authorized by all necessary corporate, limited liability company or partnership action, (c) do not contravene any articles or certificate of incorporation or bylaws, partnership or limited liability company agreement binding on or affecting such Credit Party, (d) do not contravene any law or any contractual restriction binding on or

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affecting such Credit Party, (e) do not result in or require the creation or imposition of any Lien prohibited by this Agreement, and (f) do not require any authorization or approval or other action by, or any notice or filing with, any Governmental Authority. At the time of each Advance or the issuance, renewal, extension or increase of each Letter of Credit, such Advance and the use of the proceeds of such Advance or the issuance, renewal, extension or increase of such Letter of Credit are within the Borrower’s corporate power, have been duly authorized by all necessary action, do not contravene (i) the Borrower’s certificate or articles of incorporation or bylaws, or (ii) any Legal Requirement or any material contractual restriction binding on or affecting the Borrower, will not result in or require the creation or imposition of any Lien prohibited by this Agreement, and do not require any authorization or approval or other action by, or any notice or filing with, any Governmental Authority.

Section 4.3 Enforceability . The Credit Documents have each been duly executed and delivered by each Credit Party that is a party thereto and each Credit Document constitutes the legal, valid, and binding obligation of each Credit Party that is a party thereto enforceable against such Credit Party in accordance with its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, or similar laws at the time in effect affecting the rights of creditors generally and by general principles of equity whether applied by a court of law or equity.

Section 4.4 Financial Condition .