CARBON SUPPLY AGREEMENT BETWEEN RED RIVER ENVIRONMENTAL PRODUCTS, LLC SELLER AND LUMINANT GENERATION COMPANY LLC BUYER Dated as of September 3, 2008

Exhibit 10.49

September 3, 2008

CARBON SUPPLY AGREEMENT

BETWEEN

RED RIVER ENVIRONMENTAL PRODUCTS, LLC

SELLER

AND

LUMINANT GENERATION COMPANY LLC

BUYER

Dated as of September 3, 2008

* indicates portions of the exhibit that have been omitted pursuant to a request for confidential information. The non-public information has been filed with the Commission.

September 3, 2008

TABLE OF CONTENTS

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September 3, 2008

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September 3, 2008

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September 3, 2008

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September 3, 2008

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CARBON SUPPLY AGREEMENT

This CARBON SUPPLY AGREEMENT (this “ Agreement ”) is made and entered into as of the 3rd day of September, 2008, by and between Red River Environmental Products, LLC, a Delaware limited liability company (“ Seller ”), and Luminant Generation Company LLC, a Texas limited liability company (“ Buyer ”). Together, Seller and Buyer are “ Parties ” to this Agreement and either Seller or Buyer individually is a “ Party ” to this Agreement.

RECITALS

WHEREAS, Seller is developing an activated carbon manufacturing facility in Coushatta, Louisiana which is targeted to commence operations in the first quarter of 2010;

WHEREAS, Seller desires to fulfill its obligations under this Agreement (i) by manufacturing Carbon at its Louisiana facility or an Alternative Source and (ii) by selling such Carbon to Buyer in accordance with the terms, and subject to the conditions, of this Agreement; and

WHEREAS, Buyer desires to purchase from Seller, and Seller desires to sell to Buyer, Carbon in the amounts and upon the terms and conditions set forth in this Agreement.

AGREEMENT

NOW THEREFORE, in consideration of the mutual covenants and obligations stated in this Agreement, the receipt and sufficiency of which the Parties acknowledge, Seller and Buyer hereby agree as follows:

SECTION 1. DEFINED TERMS

The words and phrases listed in Section 1 shall have the meanings ascribed to them in Section 1 wherever they appear in this Agreement as defined terms, which shall be indicated by initial capital letters in each word. Capitalized words and phrases contained in this Agreement that are not listed in Section 1 of this Agreement shall be defined in the particular Section(s) in which they are used.

“Actual Carbon Purchase” shall have the meaning given in Section 9.6.

“Additional Pounds” shall have the meaning given in Section 4.4.

“Adjustment Index” shall mean the index described in Section 9.2.2.

“Affiliate” with respect to any specified Person shall mean any other Person or entity with control over or subject to control by, or under direct or indirect common control with, such specified Person. For purposes of this definition, “control” when used with respect to a specific Person (including the Parties) means the power to direct the management and policies of such Person, directly or indirectly, whether through the ownership of voting securities, by contract, or otherwise. Notwithstanding the foregoing, in no event shall either Party be deemed an Affiliate of the other Party for the purposes of this Agreement.

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“Agreement” shall mean this Carbon Supply Agreement and all modifications and supplements hereto implemented in accordance with this Agreement.

“Alternate Source(s)” shall have the meaning set forth in Section 6.1 and shall be a source or sources from which Seller will provide Carbon other than Carbon produced by Seller at Seller’s Facility.

“Annual Delivered Amount” shall have the meaning given in Section 9.4.

“Annual Maximum” shall have the meaning given in Section 4.2.

“Annual Minimum” shall have the meaning given in Section 4.2.

“Annual Nomination” refers to the total number of pounds of Carbon that Buyer instructs Seller to deliver during each Contract Year, in accordance with Section 4.2 of this Agreement.

“Annual Shortfall” shall have the meaning given in Section 9.4.

“Applicable Laws” shall mean any laws, statutes, ordinances, regulations, rules, notice requirements, court decisions, agency guidelines, permits, principles of law and orders of any Governmental Authority which are applicable to Buyer or Seller, whichever the case may be.

“ASTM” shall have the meaning given in Section 12.2.

“Base Price” shall have the meaning given in Section 9.2.1.

“Business Day” shall mean any Day other than a Legal Holiday.

“Buyer” shall have the meaning set forth in the Preamble to this Agreement and includes Buyer’s successors and permitted assigns under this Agreement.

“Buyer Group” shall mean Buyer, its officers, directors, employees, and agents, and each of its Affiliates and each of their respective officers, directors, employees and agents.

“Buyer’s Facility” shall mean any one or more of the power generation facilities listed in Exhibit 8.

“Buyer’s Letter of Credit” shall have the meaning given in Section 25.3.

“Buyer’s Letter of Credit Amount” shall have the meaning given in Section 25.3.

“Carbon” shall mean the powdered activated carbon supplied by Seller to Buyer hereunder, which conforms to the Specifications.

“Carbon Purchase Commitment” shall have the meaning given in Section 4.1.

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“Claims” shall have the meaning given in Section 26.1.

“Contract Price” shall have the meaning given in Section 9.1.

“Contract Year” shall mean (i) the period beginning on the Day on which Buyer first takes Carbon pursuant to this Agreement and ending on December 31 of such calendar year for the first Contract Year, and (ii) for each other calendar year during the Term, the annual period beginning on January 1 and ending on December 31 of such calendar year except that if this Agreement is terminated in accordance with the terms hereof in the middle of the year, the last Contract Year ends on the effective date of termination.

“Cover Standard for Buyer” shall have the meaning given in Section 15.2.1.1.

“Cover Standard for Seller” shall have the meaning given in Section 15.2.1.2.

“CPI-U” shall have the meaning given in Section 9.2.2.

“Credit Agreement” shall mean the agreement between Seller and the entity or entities which provide necessary debt funding to Seller for the development and construction of Seller’s Facility.

“Day” shall mean calendar day unless the context in which the term “day” is used clearly indicates that a Business Day is indicated. The word day shall have such meaning whether or not the initial letter is capitalized.

“Deficit Payment” shall have the meaning given in Section 9.6.

“Early Supply” shall mean those volumes designated as “Early Supply Volumes” on Exhibit 2.

“Early Supply Milestone” shall mean the Milestone designated as “Delivery of Carbon to Buyer from any Source” in Exhibit 4.

“Effective Date” shall have the meaning given in Section 2.1.

“EPA” shall have the meaning given in Section 5.2.

“Event of Default” shall have the meaning given in Section 15.1.

“Extension Period” shall have the meaning given in Section 2.4.

“Final Analysis” shall have the meaning given in Section 12.2.

“Final LC Expiration Date” shall have the meaning given in Section 25.2.

“Financial Close” shall mean when each of the conditions precedent to closing listed in the Credit Agreement have been satisfied or waived in accordance with the terms thereof and the initial funding thereunder has occurred.

“Financial Close Milestone” shall mean the Milestone designated as “Financial Close” in Exhibit 4.

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“Financing” shall have the meaning given in Section 17.5.

“Financing Participant” shall have the meaning given in Section 17.5.

“First Year” shall have the meaning given in Section 4.2.

“Force Majeure” shall have the meaning given in Section 14.1.

“Force Majeure Period” shall have the meaning given in Section 14.2.

“Governmental Authority” shall mean any nation or government (including, without limitation, the government of the United States), any state, county, municipal or other political subdivision thereof and any Person lawfully exercising legislative, judicial, regulatory or administrative functions of or pertaining to the government.

“Legal Holiday” shall mean Saturday, Sunday or any Day on which banking institutions in New York, New York are authorized by law, regulation or executive order to remain closed.

“Milestone” shall mean the events identified as “Milestones” in Exhibit 4.

“Notice” shall mean a notice given in accordance with and complying with the requirements of Section 19.

“Party” shall mean either Buyer or Seller and “Parties” shall mean both Buyer and Seller.

“Person” shall mean any individual, limited liability company, partnership, corporation, association, business trust, or other entity or Governmental Authority.

“Point of Delivery” shall mean Buyer’s Facility.

“Poundage Variations” shall have the meaning given in Section 4.3.

“Purchase Deficit” shall have the meaning given in Section 9.6.

“Purchased Carbon” shall have the meaning given in Section 9.6.

“Reduction Notice” shall have the meaning given in Section 4.1.

“Referee Analysis” shall have the meaning given in Section 12.5.3.

“Seller” shall have the meaning set forth in the Preamble to this Agreement and includes Seller’s successors and permitted assigns under this Agreement.

“Seller Analysis” shall have the meaning given in Section 12.2.

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“Seller Group” shall mean Seller, its officers, directors, employees, and agents, and each of its Affiliates and each of their respective officers, directors, employees and agents.

“Seller’s Facility” shall mean the first production line at Seller’s carbon production facility located in Coushatta, Louisiana.

“Seller’s Letter of Credit” shall have the meaning given in Section 25.2.

“Seller’s Letter of Credit Amount” shall have the meaning given in Section 25.2.

“Specifications” shall have the meaning given in Section 5.1.

“Starting Delivery Date” shall have the meaning given in Section 2.2.

“Term” shall have the meaning given in Section 2.3.

“Threshold Event” shall mean that point in time when Seller has entered into contracts for the sale of carbon from Seller’s Facility, each contract with a term greater than one year, and which, in the aggregate, are for volumes equal to or in excess of 400 million pounds of carbon during the Term of this Agreement.

“Threshold Notice” shall have the meaning given in Section 4.1.

“Threshold Overage” shall have the meaning given in Section 4.1.

SECTION 2. CONTRACT TERM

2.1 Effective Date. The “ Effective Date ” shall be the date of this Agreement as first set forth in this Agreement.

2.2 Starting Delivery Date. At least sixty (60) days before the date on which Carbon deliveries will commence under this Agreement (the “ Starting Delivery Date ”), which date shall be a Business Day, Buyer shall provide Notice to Seller of such Starting Delivery Date. The Starting Delivery Date shall be no earlier than February 15, 2009 and deliveries for the calendar year 2009 shall not exceed * in the aggregate. In any event, the Starting Delivery Date shall not be later than April 30, 2009.

2.3 Term. The “ Term ” of this Agreement shall begin on the Effective Date and shall continue thereafter to and including December 31, 2014. Notwithstanding the foregoing, Buyer shall have the right, but not the obligation, to terminate this Agreement on or after the date on which Buyer has purchased the entire Carbon Purchase Commitment. In such event, Buyer shall have no further liability to Seller hereunder.

2.4 Term Extensions. The initial Term shall be extended for one successive three year period (the “ Extension Period ”) if the Parties, in each Party’s sole discretion, mutually agree on Carbon pricing and/or price escalation methodology for the Extension Period, on or before sixty (60) days prior to the end of the initial Term.

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SECTION 3. OUTLINE OF THE OBLIGATIONS OF THE PARTIES

3.1 Purpose. The purpose of this Section 3 is to state in brief form a summary of the obligations of the Parties under this Agreement. Notwithstanding this Section 3, Buyer and Seller expressly intend that all the promises, covenants and other obligations contained in any portion of this Agreement shall be performed as fully and faithfully as the obligations stated in this Section 3.

3.2 Obligations of Seller or Seller’s Affiliate(s). Subject to the terms and conditions of this Agreement, Seller or Seller’s Affiliate(s) shall perform the following obligations:

3.2.1 Achieve the Milestones by the applicable dates set forth in Exhibit 4.

3.2.2 Sell Carbon to Buyer pursuant to the pricing methodology set forth in Section 9 from either Seller’s Facility or an Alternate Source of the quality specified in Exhibit 1 and in the quantities specified in Exhibit 2 in accordance with the schedules established pursuant to this Agreement as those quantities may be adjusted as set forth herein.

3.2.3 Cause such Carbon to be delivered to Buyer at Buyer’s Facility in accordance with Section 8.

3.2.4 Issue monthly invoices for Carbon as specified by this Agreement.

3.2.5 Maintain adequate books and records with respect to its obligations and performance under this Agreement.

3.2.6 Seller may perform its obligations hereunder directly or cause such obligations to be performed by any of its Affiliates, contractors or other designees; provided that Seller shall at all times remain responsible to Buyer for the full and timely performance of its obligations hereunder.

3.3 Obligations of Buyer. Subject to the terms and conditions of this Agreement, Buyer shall perform the following obligations:

3.3.1 Except to the extent Seller does not deliver Carbon due to Seller’s breach or a Force Majeure event preventing Seller’s performance, purchase the Carbon Purchase Commitment as described in Section 4 and as set forth in Exhibit 2 and accept delivery of, or pay for if not accepted, such Carbon in accordance with the schedules established pursuant to this Agreement.

3.3.2 Pay the applicable Contract Price for Carbon delivered and accepted in accordance with this Agreement and any other amounts owed by it hereunder as and when due in accordance with this Agreement.

SECTION 4. CARBON QUANTITIES AND DELIVERY SCHEDULES

4.1 Quantity Obligations. Buyer shall take from Seller and pay for, or pay for, if not taken, the minimum quantities specified in Exhibit 2, as such minimum quantities may be amended as herein set forth (the “ Carbon Purchase Commitment ”), except to the extent Seller does not deliver Carbon due to Seller’s breach or a Force Majeure event preventing Seller’s performance. In such event,

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Buyer’s Carbon Purchase Commitment shall be reduced on a pound for pound basis to account for such event; provided, however , that if such event leads to termination of this Agreement in accordance with its terms, the Carbon Purchase Commitment will terminate upon such termination. Subject to the Carbon Purchase Commitment and terms and conditions of this Agreement, during each Contract Year, Seller shall tender and sell to Buyer at the Point of Delivery, and Buyer shall purchase from Seller, the total quantity of Carbon specified in Buyer’s Annual Nomination pursuant to Section 4.2, as such Annual Nomination may be revised from time to time in accordance with Section 4.3 and other applicable provisions of this Agreement; provided, further , that Buyer’s Annual Nomination shall at all times be consistent with achieving Buyer’s full Carbon Purchase Commitment during the term of this Agreement, except to the extent that Buyer is not obligated to purchase such full Carbon Purchase Commitment as set forth above. Further, to the extent Seller does not use commercially reasonable efforts to sell Carbon that Buyer fails to accept as contemplated by the definition of “Cover Standard for Seller”, Buyer’s Carbon Purchase Commitment shall be reduced by the amount of Carbon Seller would have been able to sell had it used such commercially reasonable efforts as contemplated by such definition.

Buyer shall have the one time right to increase the Carbon Purchase Commitment that is set forth on Exhibit 2 by notifying Seller in writing on or before January 1, 2009 of its election to increase such commitment by any amount up to, but not in excess of, the annual amounts set forth on Exhibit 2A. If Buyer does not so elect on or before January 1, 2009 to increase such commitment, the Carbon Purchase Commitment shall remain as set forth on Exhibit 2. However, if Buyer elects to increase its commitment as provided in this paragraph, the Carbon Purchase Commitment set forth on Exhibit 2 shall be revised in accordance with Buyer’s election and the new Carbon Purchase Commitment shall be as so revised.

Notwithstanding the foregoing, if the Threshold Event occurs, Seller shall, within thirty (30) Days after such event, notify Buyer in writing that the Threshold Event has occurred (the “ Threshold Notice ”) and specifying the amount by which the sales volume has exceeded * (the “ Threshold Overage ”). Within sixty (60) Days after Buyer’s receipt of the Threshold Notice, Buyer shall have the option during such period, but not the obligation, to notify Seller in writing that it has elected to reduce its Carbon Purchase Commitment (the “ Reduction Notice ”). Such option must be exercised during such notice period and such option may only be exercised once. The Reduction Notice shall include the amount by which Buyer elects to reduce its Carbon Purchase Commitment; provided, however , that such reduction shall not exceed in the aggregate *; provided, further, however , that if Buyer advises that it wishes to reduce its Carbon Purchase Commitment in an amount up to the * and such requested amount exceeds the Threshold Overage, the Carbon Purchase Commitment shall only be reduced in the amount of the Threshold Overage unless and until *. In the case where the Threshold Overage is insufficient to allow reduction of the Carbon Purchase Commitment in the full amount requested by Buyer in the Reduction Notice, Buyer’s Carbon Purchase Commitment shall be subsequently reduced if *. The Carbon Purchase Commitment shall be reduced as set forth above, and the amount as reduced shall become the new Carbon Purchase Commitment for all sales beginning on the first of the month following Seller’s receipt of the Reduction Notice. The Annual Minimum set forth in Section 4.2 shall also be reduced proportionately. Prior to the occurrence of the Threshold Event, Seller shall notify Buyer within thirty (30) Days after each contract for the sale of carbon which contributes to achieving the Threshold Event.

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4.2 Nominations. At least sixty (60) Days prior to the Starting Delivery Date, the Parties shall mutually agree on a start-up schedule and the amount of Carbon to be delivered on a monthly basis through the remainder of the Contract Year in which deliveries start (the “ First Year ”). On or before November 1 of each succeeding Contract Year, Buyer shall nominate the pounds of Carbon to be delivered in the following Contract Year, broken down into monthly amounts. Each such Annual Nomination shall be no less than *% of the pounds set forth on Exhibit 2 for such Contract Year (the “ Annual Minimum ”) and no greater than *% of the pounds set forth on Exhibit 2 for such Contract Year (the “ Annual Maximum ”). The Annual Minimum and the Annual Maximum shall be reduced and prorated on a monthly basis for Contract Years that are less than twelve months. Buyer may revise the Annual Nomination within the foregoing limits, and in accordance with the notification requirements for Poundage Variations specified in Section 4.3. The term “ Annual Nomination ” as used in this Agreement shall reflect the actual nomination amount in effect from time to time. Notwithstanding the foregoing, if upon the execution of this Agreement or upon the exercise of Buyer’s right to increase the Carbon Purchase Commitment as provided in Section 4.1, the Carbon Purchase Commitment is *.

4.3 Poundage Variations. Buyer may, at its sole discretion and for any reason, increase or decrease any monthly quantity to reflect its revised expectation of its Carbon needs upon at least thirty (30) Days prior Notice to Seller (“ Poundage Variations ”); provided that such an increase or decrease shall not cause the Annual Nomination to be greater than the Annual Maximum or less than the Annual Minimum; and provided, further that on a * basis Buyer will accept no less than fifteen *% of its Annual Nomination. The Parties acknowledge that Buyer shall have the right to reduce the monthly quantity to as low as zero if necessary to accommodate a Force Majeure event.

4.4 Additional Pounds. In the event that Buyer desires and/or needs to purchase Carbon in excess of the Annual Maximum for any Contract Year, Seller shall, in good faith, determine whether such additional pounds (the “ Additional Pounds ”) can be supplied by Seller. If the Additional Pounds are not available for supply to Buyer, then Seller shall promptly (and, in any event, within ten (10) Days) provide Notice thereof to Buyer.

SECTION 5. PRODUCT WARRANTY AND PERFORMANCE GUARANTY

5.1 Warranty. Seller warrants and represents that the Carbon delivered to Buyer shall be free of any liens or encumbrances. Seller further warrants that all Carbon sold and delivered to Buyer under this Agreement shall conform strictly to the “Product Specifications” set forth in Exhibit 1 (“ Specification(s ) ”) and have the “Typical Properties” set forth in Exhibit 1 pursuant to industry standards. Carbon shall be tested in accordance with the testing protocols set forth in Exhibits 1A and 1B. As set forth in such protocols, it is the Parties’ intent to test Carbon for acceptance prior to shipment to avoid unnecessary transportation of substandard Carbon and avoid possible intermingling of substandard Carbon with acceptable Carbon. Buyer shall have the right to request, and Seller shall provide if so requested, a pre-shipment sample of any Carbon scheduled for delivery. Buyer shall either (i) release such Carbon for delivery, or (ii) reject such Carbon, within twenty-four (24) hours of the time Seller tenders the Carbon shipment for such pre-shipment sample. If Buyer does not accept or reject such Carbon within such twenty-four (24) hour period, such Carbon shall be

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deemed accepted. For all deliveries that are made without the requirement for a pre-shipment sample, the certificate of analysis required under Section 12.5.1 will be deemed to represent the actual product quality. The Parties acknowledge that there is no practical way to remove the Carbon from Buyer’s silo so any Carbon delivered to the silo must be used by Buyer. Buyer shall have the right to test any lots within the thirty (30) Day sample retention period specified in Section 12.5.2 and if Buyer’s analysis is outside of the Specifications, the procedures outlined in 12.5.3 will be used to determine the final product quality. If the Referee Analysis contemplated by Section 12.5.3 shows that the Carbon does not meet the Specifications and the result to Buyer is additional Carbon usage, Seller will provide at no cost the additional pounds required to meet the standard performance curve, provided that Buyer can provide accurate verification of the additional carbon usage.

5.2 Performance Benchmark. Given the limited or non-existent activated carbon injection performance data available for individual units of Seller’s Facility, a period of three months as mutually selected by the Parties will be set aside to establish benchmark performance curves for each unit. The Parties acknowledge that the goal during these test periods is to establish a performance curve for controlling total vapor-phase mercury emissions by conducting short-term parametric tests at different injection rates. The test results will then be used to determine the carbon quantities needed to meet the chosen mercury removal rates. Performance data will be measured using U.S. Environmental Protection Agency (“ EPA ”) certifiable mercury continuous emissions monitoring systems that meet certification requirements outlined in EPA’s now vacated Clean Air Mercury Rule at pre-activated carbon injection and post particulate collection device extraction locations. Mercury measurement and reporting for the tests described in this Section 5.2 will be monitored by Seller but paid for by Buyer.

5.3 REMEDY; DISCLAIMER OF IMPLIED WARRANTIES. THE WARRANTY AND REMEDY FOR SUCH WARRANTY AS SET FORTH IN SECTION 5.1 ABOVE IS IN LIEU OF ALL OTHER WARRANTIES AND REMEDIES, REPRESENTATIONS OR CONDITIONS OF ANY KIND OR NATURE, EXPRESS OR IMPLIED, IN FACT OR IN LAW, WITH RESPECT TO THE CARBON SUPPLIED HEREUNDER, INCLUDING, WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

SECTION 6. SOURCE OF CARBON

6.1 Source of Carbon. Commencing on the date identified on Exhibit 4 as the date for “Delivery of Carbon to Buyer from Seller’s Facility”, the Carbon delivered pursuant to this Agreement shall be manufactured by Seller at Seller’s Facility; provided, however , that Seller shall be permitted to provide Carbon from any alternate sources developed by Seller in accordance with the terms of this Agreement (the “ Alternate Sources ”) for periods when:

a. Seller’s Facility is under construction, or

b. events of Force Majeure or other events cause a temporary outage or temporary significant production reduction at the Seller’s Facility, or

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c. short term business conditions otherwise necessitate supply from Alternate Sources to meet Seller’s contractual schedule and quantity commitments in the reasonable judgment of Seller.

During its development of Alternate Sources, Seller shall provide Buyer with regular updates on Seller’s development efforts with Alternate Sources and Seller shall further provide Alternate Sources information and site access reasonably requested by Buyer for the purpose of Buyer confirming the Alternate Sources’ viability to provide carbon in accordance with the Specifications and in quantities represented by Seller. When and if Alternate Sources are to be used, Seller shall provide written notice to Buyer. Seller shall be obligated to make all commercially reasonable efforts to minimize the period(s) when Alternate Sources are used. Seller will provide Carbon from Alternate Sources for Early Supply commencing on or before the date set forth for the Early Supply Milestone in Exhibit 4. If Seller elects to deliver Carbon from Alternate Sources, Seller shall pay directly or reimburse Buyer for all reasonable transportation costs incurred to transport such Carbon to Buyer’s Facility to the extent such costs exceed the costs Buyer would have incurred if such Carbon had been transported from Seller’s Facility.

SECTION 7. DELIVERY OF CARBON

7.1 Delivery Terms. Seller shall deliver the Carbon to Buyer’s Facility FOB Destination Prepaid and Added. Buyer is responsible for costs of insurance and freight in addition to the Base Price, with Seller to be the loss payee for such insurance. Seller shall arrange for loading of Carbon at Seller’s Facility.

7.2 Title and Risk of Loss. Title and risk of loss and damage to Carbon shall pass to Buyer at the Point of Delivery. Seller warrants that it will pass to Buyer full title to such Carbon free and clear of all liens and encumbrances. Seller assumes no liability for the Carbon after title and risk of loss pass to Buyer, except as otherwise specifically provided in this Agreement. Title and risk of loss and damage to Carbon Buyer rightfully rejects in accordance with Section 5 shall remain with Seller.

SECTION 8. TRANSPORTATION OBLIGATIONS

8.1 Transport. Seller shall arrange for the transport of Carbon supplied by Seller hereunder to the Point of Delivery. Transportation arranged by Seller shall be of sufficient capacity to accommodate the transport of the Annual Nominations made (and adjusted) pursuant to Section 4 of this Agreement. Buyer shall pay all of the documented costs (including insurance and freight) for such shipment to the Point of Delivery in accordance with the cost methodology set forth in Exhibit 5, which costs shall be directly billed to Buyer by the shipping companies to the extent possible. Seller shall at all times comply with Buyer’s reasonable requests regarding selection and management of shipping and shall provide Buyer access to all of Seller’s documents and records regarding shipment costs and expenses. Seller’s delivery agent shall be responsible for the unloading of Carbon at Buyer’s Facility. Seller shall use or cause to be used transport equipment that is in good condition, clean, and ready to load.

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If at any time during the term of this Agreement Buyer elects to arrange for the transportation of Carbon from Seller’s Facility to the Point of Delivery, Buyer shall provide Seller with not less than thirty (30) Days written notice prior to the date on which Buyer elects to assume responsibility for transportation. Notwithstanding the foregoing, if at any time Buyer fails to provide transportation in accordance with the delivery schedule set forth herein and such failure adversely impacts Seller’s operations, then Seller shall have the right to arrange for transportation as set forth in the preceding paragraph and Buyer shall pay all such documented costs.

SECTION 9. PRICE OF CARBON

9.1 Contract Price. The “ Contract Price ” for any calendar month after the Starting Delivery Date is an amount equal to (without duplication) (i) the Base Price (determined as provided in Section 9.2), multiplied by (ii) the number of pounds of Carbon delivered during such month.

9.2 Calculation of Base Price.

9.2.1 Base Price. The “ Base Price ” for Carbon delivered by Seller to Buyer at the Point of Delivery in accordance with this Agreement shall be that price per pound set forth on Exhibit 3. The Base Price does not include the cost of freight and insurance, which is Buyer’s responsibility pursuant to Sections 7.1 and 8.1. The Base Price set forth in Exhibit 3 shall be subject to escalation in accordance with Section 9.2.2 and billings shall be reconciled annually in accordance with Section 9.4.

9.2.2 * Adjustment. Commencing on January 1, 2011, the Base Price in Exhibit 3 shall be adjusted, and adjusted annually thereafter, as of the first day of each calendar year by increasing the Base Price by a percentage equal to each positive percentage point of change, or proportionately for fractional parts of a positive percentage point of change, *. The * used to determine the percentage change to be effective on January 1, 2011 shall be the * published for January 2010. For example, the Base Price in effect for deliveries in 2010 shall be adjusted for deliveries beginning on January 1, 2011 by a percentage equal to each positive percentage point of change, or proportionately for fractional parts of a percentage point of change, to reflect the positive cumulative changes in the * between January 1, 2010 and January 1, 2011. The Base Price, as adjusted, shall be the new Base Price for the period January 1, 2011 to December 31, 2011. Similarly, effective January 1, 2012, the new Base Price shall be adjusted again for each positive percentage point of change, or proportionately for fractional parts of a percentage point of change, to reflect cumulative positive changes in the * between January 1, 2011 and January 1, 2012. The Base Price shall continue to be adjusted annually on January 1 of each year for the remainder of the Term of this Agreement. Notwithstanding the foregoing, the percentage of annual positive adjustment in the Base Price shall not exceed * percent (*%) in any year during the term of this Agreement.

Exhibit 3 to this Agreement contains an example of the calculations pursuant to this Section 9.2.2.

9.2.3 Notice of Calculations. Seller shall calculate the * adjustment to the Base Price pursuant to Section 9.2.2 for each Contract Year and provide Notice to Buyer of the new Base Price to be applicable for such Contract Year prior to January 30 of such year. Seller’s Notice shall provide sufficient detail regarding how such calculations were made.

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9.3 Taxes, Fees and Royalties. All taxes, fees and royalties are included in the Base Price other than any applicable state sales tax, which shall be to Buyer’s account. In the event that subsequent to the execution of this Agreement, a Governmental Authority makes a change in tax law that materially impacts the cost of producing and supplying Carbon, such as, without limitation, issuance of a new carbon tax, Seller shall so advise Buyer and provide substantiation of the cost impact as reasonably requested by Buyer. Seller and Buyer shall thereafter negotiate in good faith an equitable adjustment in the Base Price to account for such cost impact.

9.4 Annual Reconciliation of Carbon Purchase Quantity. Within thirty (30) Days after the end of each Contract Year, Seller shall total all deliveries of Carbon to Buyer and determine the annual quantity of Carbon actually delivered (the “ Annual Delivered Amount ”). If the Annual Delivered Amount is less than the Annual Minimum, as such amount may be adjusted in accordance with this Agreement, then Buyer shall pay to Seller the amount calculated by taking the difference between the Annual Minimum and the Annual Delivered Amount (the “ Annual Shortfall ”) and multiplying such amount by the Base Price(s) in effect for the Contract Year. If the first Contract Year after commencement of deliveries is not a full calendar year, the determination of the Annual Minimum shall be appropriately prorated to reflect the actual period of deliveries (e.g., if deliveries commence on July 1, then the Annual Minimum would be one-half the Annual Minimum specified in 4.2).

9.5 Rounding. Unless otherwise specifically provided by this Agreement, the values used to perform the calculations prescribed by this Agreement shall be rounded to three (3) decimal places. For invoicing purposes, the dollar amounts of charges and credits shall be rounded to the nearest cent. For purposes of adjusting values in accordance with this Section 9, the Adjustment Index shall be rounded to the nearest hundredth of an index point. The annual percentage changes for the Adjustment Index shall be rounded to the nearest hundredth of a percentage point. The Base Price adjusted pursuant to Section 9 shall be rounded to two (2) decimal places.

9.6 End of Term Reconciliation of Carbon Purchased Versus Carbon Purchase Commitment. Within thirty (30) Days after the end of the Term of this Agreement, Seller shall determine the actual quantity of carbon delivered to Buyer (the “ Actual Carbon Purchase ”) plus the quantity, if any, of Annual Shortfalls paid for by Buyer pursuant to 9.4 above for failure to meet Annual Minimums (collectively the Actual Carbon Purchase plus the quantity of all paid for Annual Shortfalls total the “ Purchased Carbon ”) and shall reconcile the Purchased Carbon against the quantity of the Carbon Purchase Commitment as such commitment may be adjusted as herein provided. Seller shall provide such determination to Buyer in writing within thirty (30) Days after the end of the Term. If the Purchased Carbon quantity is less than the Carbon Purchase Commitment (a “ Purchase Deficit ”), Buyer shall pay to Seller an amount equal to the Base Price times the Purchase Deficit ( the “ Deficit Payment ”). Such payment shall be Seller’s sole and exclusive remedy for Buyer’s failure to meet its Carbon Purchase Commitment, and Seller’s consequent loss of revenues. In the event that the Purchased Carbon exceeds the Carbon Purchase Commitment, the Parties shall have no further obligations to each other hereunder. To the extent that Seller has production capacity available at the end of the Term of this Agreement and Buyer has a

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Purchase Deficit and/or has paid for Carbon that it has not taken, Buyer shall have the right, but not the obligation, to extend this Agreement by a period of twelve (12) months in order to take delivery of the amount of the Purchase Deficit and any Carbon paid for, but not taken; provided that Buyer provides Notice of such extension to Seller and makes the Deficit Payment within thirty (30) Days after the date when Seller notifies Buyer of the Purchase Deficit.

9.7 *. *, if Seller has executed or hereafter executes a carbon supply agreement for the sale of carbon from Seller’s Facility with a third party that is substantially equivalent in contract term and volumes to this Agreement and has a lower price per pound for carbon than as set forth in this Agreement (each, a “ Third Party Agreement ” ), Buyer may elect to accept the price contained in the Third Party Agreement; provided, however, that in the event Buyer elects to accept the price contained in the Third Party Agreement, Sections 4, 9, 15 and 25 of this Agreement shall also be revised to be substantially equivalent to terms of the Third Party Agreement. * .

SECTION 10. INVOICING AND PAYMENT

10.1 Invoicing Procedures. Seller shall invoice Buyer monthly for deliveries under this Agreement. On or before the tenth (10th) Day of each month of a Contract Year, Seller shall send Buyer an invoice for all Carbon delivered to and accepted by Buyer during the preceding month priced in accordance with Article 9 and the Final Analysis as provided in Section 12 .

10.2 Payment Procedures. Buyer shall pay undisputed invoices by wire transfer within thirty (30) Days after the receipt of each monthly invoice. If Seller does not receive timely payment of undisputed amounts, then interest shall be charged at the prime rate in effect on that date (as set by the Chase Manhattan Bank of New York on ninety (90) Day commercial loans as of the date payment is due) plus one and one-half percent (1.5%), but in no event in excess of the highest rate allowed by Applicable Law.

10.3 Disputed Invoices. Buyer shall pay all invoices issued by Seller in accordance with this Section 10, except those portions of any invoice that Buyer formally disputes in a Notice to Seller, which Notice Buyer shall submit to Seller within fifteen (15) Days after receiving the invoice. Buyer shall pay all undisputed portions of each disputed invoice. The Parties shall make every reasonable effort to settle invoice disputes promptly through good faith negotiations. Payment of disputed amounts shall be made within ten (10) Days following the date of settlement. Thereafter, such amounts shall accrue interest at the late payment rate established pursuant to Section 10.2. Notwithstanding the foregoing, Buyer’s reasonable dispute of an invoice shall not constitute an Event of Default, nor constitute cause for Seller to delay or suspend performance under this Agreement.

SECTION 11. COMPLIANCE WITH LAWS

11.1 Construction. In performing this Agreement Buyer and Seller shall not knowingly violate any Applicable Laws; provided, however , that no such violation shall constitute an Event of Default by a Party unless it results in a material non-performance of the Party’s other performance obligations under this Agreement. Buyer and Seller shall interpret and construe this Agreement to achieve lawful results.

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11.2 Severability. If any portion of this Agreement becomes or is determined by a Governmental Authority with jurisdiction to be illegal, Buyer and Seller shall modify that portion to correct the illegality. The illegality of any portion of this Agreement shall not affect the validity or the enforceability of the remainder of this Agreement.

SECTION 12. WEIGHING, SAMPLING, AND ANALYSIS

12.1 Procedures. Weighing, sampling, and analysis of the Carbon tendered for delivery shall be carried out in accordance with the provisions of this Section 12.

12.2 Duties to Sample Carbon. Seller shall collect samples at Seller’s Facility in accordance with the testing protocols set forth in Exhibits 1A and 1B. The sampling shall be conducted at Seller’s Facility and in a statistically reliable method that is in compliance with procedures approved by the American Society for Testing and Materials (“ ASTM ”). Seller shall, subject to the protocols set forth in Exhibits 1A and 1B, perform or cause to be performed an analysis of each lot or batch of Carbon produced by Seller to determine the characteristics of the Carbon (each, a “ Seller Analysis ”). The methods and procedures to be used in the sampling process and laboratory analysis shall be in compliance with those approved by the ASTM, or such other methods and procedures mutually agreed to in writing by the Parties. Unless Buyer requests a Referee Analysis pursuant to Section 12.5.3, the results of each Seller Analysis shall be deemed the final analysis and be binding as the analysis for determining whether the carbon meets the Specifications (the “ Final Analysis ” ). If Buyer requests a Referee Analysis pursuant to Section 12.5.3, the results of such Referee Analysis shall be the Final Analysis. The foregoing notwithstanding, Buyer shall have the right at any time to conduct sampling and analysis of Carbon delivered to Buyer and if such testing reveals a discrepancy with the results obtained by Seller, the Parties shall confer and resolve any issues as set forth in Section 12.5.3.

12.3 Duties of Seller to Weigh Carbon.

12.3.1 Duty to Weigh; Use of Weighing Data. Seller shall weigh or cause to be weighed all Car