that period of time commencing on the Expansion Commencement Date and expiring contemporaneouslywith the Lease on the Expiration Date, as defined in Section 1.11 of the Lease.          (d) Acceptance. Effective on the Expansion Commencement Date, Landlord hereby leasesto Tenant and Tenant hereby leases from Landlord, on the terms and conditions set forth in theLease and herein, the Expansion Premises. Tenant shall accept the Expansion Premises in itspresent “as is” condition, provided that Landlord shall delivery the Expansion Premisessubstantially consistent with **Exhibit C-3** of the original Lease. Tenant shall complete thework set forth in the Work Letter, attached hereto as **Exhibit B** and incorporated herein bythis reference.          (e) Expansion Allowance. Landlord shall provide to Tenant an allowance equal to thelesser of (i) Two Hundred Four Thousand and No/100 Dollars ($204,000.00) (i.e., $40.00 per rentablesquare foot of space within the Expansion Premises), or (ii) the actual cost of TenantImprovements, as such term is defined in Work Letter (the “**Expansion Allowance**”). The ExpansionAllowance is subject to and shall be paid by Landlord pursuant to the terms and conditions of**Exhibit B**. Notwithstanding anything to the contrary contained herein, Tenant may elect touse the Expansion Allowance at any time prior to May 1, 2011 (provided that the final Draw Request,as set forth in Section 10(b) of **Exhibit B** is delivered to Landlord on or before suchdate).     **3. ****Base Rent****.**Tenant shall pay to Landlord Base Rent for the Expansion Premises,which shall be payable in monthly installments as follows:                   **Annual** **Expansion Premises** **Original Premises** **Total****Dates** **Rate/RSF** **Monthly Installment** **Monthly Installment** **Monthly Installment**05/01/10 — 06/30/10 $22.25  $0.00* $41,086.48  $41,086.48 07/01/10 — 10/31/10 $22.75  $0.00* $42,009.77  $42,009.77 11/01/10 — 06/30/11 $22.75  $9,668.75  $42,009.77  $51,678.52 07/01/11 — 06/30/12 $23.25  $9,881.25  $42,933.06  $52,814.31 07/01/12 — 06/30/13 $23.75  $10,093.75  $43,856.35  $53,950.10 07/01/13 — 06/30/14 $24.25  $10,306.25  $44,779.65  $55,085.90 07/01/14 — 06/30/15 $24.75  $10,518.75  $45,702.94  $56,221.69 07/01/15 — 06/30/16 $25.25  $10,731.25  $46,626.23  $57,357.48  * Base Rent, Parking Rent and Tenant’s Proportionate Share of Operating Expenses and Taxesapplicable to the Expansion Premises shall be abated for the six (6) month period beginning on theExpansion Commencement Date. Such abatement shall not apply to any amounts applicable to theOriginal Premises or to any other amounts payable under the Lease, including, without limitation,any overtime HVAC or separately metered utilities. In the event that the Expansion CommencementDate is other than the first day of a calendar month, the first and last months of the abatementperiod shall be prorated and the partial month shall be added to Month 7. Landlord and Tenantagree that the abatement of rental and other payments contained in this Section is conditional andis made by Landlord in reliance upon Tenant’s faithful and continued performance of the terms,conditions and covenants of this Lease and the payment of all monies due Landlord hereunder. Inthe event that Tenant defaults under the terms and conditions of the Lease, then the unamortizedportion of all conditionally abated rental shall become fully liquidated and immediately due andpayable (without limitation and in addition to any and all other rights and remedies available toLandlord provided herein or at law and in equity).Except as otherwise expressly set forth herein, Base Rent shall be payable pursuant to the termsand conditions of Section 4 of the Lease.
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     **4. ****Tenant’s Proportionate Share****.**Beginning on the Expansion Commencement Date,Tenant’s Proportionate Share, as defined in Section 1.13 of the Lease, shall be increased from7.251% to 8.920%, subject to the abatement of Operating Expenses and Taxes for the ExpansionPremises as set forth in Section 3 above.     **5. ****Tenant’s Parking Spaces**. The number of Tenant’s Parking Spaces, as defined inSection 1.18 of the Lease, shall be increased by twenty (20) spaces on the Expansion CommencementDate. Accordingly, the total number of Tenant’s Parking Spaces shall be increased to 109 spaces.None of the additional Parking Spaces shall be assigned or reserved; provided, however, that Tenantshall have the right to convert twenty percent (20%) of such additional Parking Spaces (e.g., four(4) of the Parking Spaces attributable to the Expansion Premises) to reserved Parking Spaces uponthirty (30) days’ prior written notice to Landlord at no additional charge during the initial LeaseTerm, the location of which shall be reasonably determined by Landlord following consultation withTenant.     **6. ****Extension Option****.**Tenant shall have the right to extend the Lease for the entirePremises (as expanded) pursuant to the Extension Option set forth in Section 2 of the Rider toLease.     **7. ****Brokers**. Tenant hereby represents and warrants to Landlord that Tenant has notdealt with any real estate brokers or leasing agents, except CB Richard Ellis, Inc. and Studley,Inc. (collectively, “**Brokers**”), in the negotiation of this Amendment, and that no commissions arepayable to any party claiming through Tenant as a result of the consummation of the transactioncontemplated by this Amendment, except to Brokers, if applicable. Tenant hereby agrees toindemnify and hold Landlord harmless from any and all loss, costs, damages or expenses, including,without limitation, all attorneys’ fees and disbursements by reason of any claim of or liability toany other broker, agent, entity or person claiming through Tenant (other than Brokers) and arisingout of or in connection with the negotiation and execution of this Amendment.     **8. ****Miscellaneous**. With the exception of those matters set forth in this Amendment,Tenant’s leasing of the Premises shall be subject to all terms, covenants and conditions of theLease. In the event of any express conflict or inconsistency between the terms of this Amendmentand the terms of the Lease, the terms of this Amendment shall control and govern. Except asexpressly modified by this Amendment, all other terms and conditions of the Lease are herebyratified and affirmed. The parties acknowledge that the Lease is a valid and enforceable agreementand that Tenant holds no claims against Landlord or its agents which might serve as the basis ofany other set-off against accruing rent and other charges or any other remedy at law or in equity.[Remainder of Page Intentionally Left Blank]
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     IN WITNESS WHEREOF, the foregoing First Amendment to Lease is dated effective as of the dateand year first written above.           **LANDLORD:**        I-10 EC CORRIDOR #2 LIMITED PARTNERSHIP, a Delaware limited partnership  By: TC HOUSTON, INC., a Delaware corporation, Managing Partner             By: /s/ W. Aaron Thielhorn Date: January 29, 2010             Name: W. Aaron Thielhorn                    Title: Vice President                             **TENANT:**        CARBO CERAMICS INC.,    a Delaware corporation               By: /s/ Gary A. Kolstad Date: January 25, 2010             Name: Gary A. Kolstad                    Title: Chief Executive Officer                  
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