MEMBERSHIP INTEREST TRANSFER AGREEMENT

This Membership Interest Transfer Agreement (this “ Agreement ”), dated as April 7, 2009, to be effective as of 11:59 PM CDT on March 31, 2009 (the “ Effective Date ”), is by and between SemMaterials Energy Partners, L.L.C., a Delaware limited liability company (“ SMEP ”), and SemMaterials, L.P., an Oklahoma limited partnership (“ SemMaterials ”).  SemMaterials and SMEP are sometimes herein referred to individually as a “ Party ” and collectively as the “ Parties .”

WHEREAS , pursuant to that certain Contribution Agreement (the “ Original Contribution Agreement ”) by and among K.C. Asphalt, L.L.C., a Colorado limited liability company (“ K.C. Asphalt ”), SemMaterials and SMEP, dated as of January 28, 2008, K.C. Asphalt and SemMaterials contributed and assigned the Prior Transferred Assets (as defined herein) to SMEP;

WHEREAS , pursuant to the Original Contribution Agreement, K.C. Asphalt and SemMaterials retained and reserved the Prior Retained Assets (as defined herein) and retained and reserved all of the rights and obligations associated with the Prior Retained Assets;

WHEREAS , pursuant to a Purchase Agreement, dated as of January 14, 2008, SemMaterials sold and transferred 100% of the limited liability company membership interests of SMEP to SemGroup Energy Partners Operating, L.L.C. on February 20, 2008;

WHEREAS , commencing on July 22, 2008, SemMaterials and certain of their Affiliates (as defined herein) filed voluntary petitions for relief under Chapter 11 of the Bankruptcy Code (as defined herein), which cases are pending in the Bankruptcy Court (as defined herein);

WHEREAS , SemMaterials is a debtor and debtor in possession in the Bankruptcy Cases (as defined herein) and is currently authorized to conduct its business under Sections 1107 and 1108 of the Bankruptcy Code;

WHEREAS , as of the Effective Date, K.C. Asphalt and SemMaterials (i) terminated the Prior Retained Easements (as defined herein), (ii) transferred, conveyed and assigned the interests previously retained in the Prior Retained Leasehold Agreements (as defined herein) to SMEP and (iii) contributed the Asphalt Processing Assets (as defined herein) to SGLP Asphalt, L.L.C., a Texas limited liability company (“ SGLP Asphalt ”), each pursuant to a Contribution Agreement (the “ Asphalt Contribution Agreement ”);

WHEREAS , SemMaterials is the sole member of SGLP Asphalt and owns 100% of the Equity Interests (as defined herein) of SGLP Asphalt (the “ Transferred Interest ”); and

WHEREAS , SemMaterials desires to transfer, convey and assign to SMEP the Transferred Interest, and SMEP desires to have the Transferred Interest transferred, conveyed and assigned to it, on the terms set forth in this Agreement.

NOW, THEREFORE , for and in consideration of the premises, the mutual covenants and agreements contained herein, and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged by the Parties, the Parties hereby agree as follows:

1.01   In this Agreement, capitalized terms used but not otherwise defined herein shall have the meaning assigned such term in the Asphalt Contribution Agreement, the terms defined in the preamble and the Recitals have the meanings indicated and the following terms will have the meanings indicated below:

“ Affiliates ” shall have the meaning given such term in Master Agreement.

“ Clawback Notice ” shall have the meaning given such term in Section 4.01(b) .

“ Clawback Payment ” shall have the meaning given such term in Section 4.01(a) .

“ Clawback Period ” shall have the meaning given such term in Section 4.01(a) .

“ Clawback Sale ” shall have the meaning given such term in Section 4.01(a) .

“ Dispute Notice ” shall have the meaning given such term in Section 4.01(c) .

“ Disputed Items ” shall have the meaning given such term in Section 4.01(c) .

“ Equity Interests ” means all limited liability company interests, units, participations or equivalents of limited liability company interests of SGLP Asphalt, however designated.

“ GAAP ” means United States generally accepted accounting principles as in effect from time to time.

           “ Net Proceeds ” means the aggregate cash proceeds received by SMEP or any of its Affiliates in respect of an asset sale that includes Asphalt Processing Assets, net of (i) the direct and indirect costs relating to such asset sale, including, without limitation, legal, accounting and investment banking fees, (ii) Taxes paid or payable as a result thereof, and (iii) the value of and any reserve for adjustment in respect of the sale price of such asset or assets established in accordance with GAAP, including, without limitation, in respect of sales price adjustments, non-competition agreements and assumed or retained liabilities associated with the asset or assets disposed of in such transaction, including, without limitation, liabilities related to environmental matters or against any indemnification obligations associated with such asset sale.

 “ Referee ” shall have the meaning given such term in Section 4.01(c) .

“ Resolution Period ” shall have the meaning given such term in Section 4.01(c) .

2.01   Conveyance of the Transferred Interests .  For good and valuable consideration, the sufficiency of which is hereby acknowledged, SemMaterials hereby transfers, assigns, conveys and delivers to SMEP, the Transferred Interests free and clear of any and all Liens (other than Permitted Exceptions).

2.02   Assumed Liabilities .  As of the Effective Date, SMEP does hereby assume and thereafter in due course will pay and fully satisfy any Liabilities associated with the Transferred Interests.

3.01   Further Assurances of SemMaterials to SMEP .  From time to time after the Effective Date, and without any further consideration, each of SemMaterials and SMEP shall execute, acknowledge and deliver such additional assignments and other conveyance documents, and will do all such other acts and things, all in accordance with Applicable Law, as may be necessary or reasonably appropriate to more fully and effectively to vest in SMEP and its successors and assigns beneficial and record title to the Transferred Interests, and/or to more fully and effectively carry out the purposes and intent of this Agreement.

4.01   Sale of the Asphalt Processing Assets .

(a)   If SMEP or any of its Affiliates (as defined in the Master Agreement) consummates a sale (other than to SMEP or any of its Affiliates), including by way of merger or consolidation, of any Asphalt Processing Assets (a “ Clawback Sale ”) during the period beginning on the Effective Date and ending on December 31, 2009 (the “ Clawback Period ”), then SMEP will pay SemMaterials 20% of the Net Proceeds received from each such sale attributable to the sold Asphalt Processing Assets (the “ Clawback Payment ”) in accordance with the terms of this Section 4.01 .

(b)   Within fifteen (15) days after a Clawback Sale consummated during the Clawback Period, SMEP shall deliver a schedule (the “ Clawback Notice ”) to SemMaterials listing the following in reasonable detail: (i) the Asphalt Processing Assets that were sold in such Clawback Sale, (ii) the assets other than Asphalt Processing Assets that were sold in such Clawback Sale, if any, (iii) an allocation of the Net Proceeds from such sale showing the Net Proceeds attributable to the Asphalt Processing Assets and the Net Proceeds attributable to assets other than Asphalt Processing Assets, if any, and (iv) the proposed Clawback Payment.

(c)   If SemMaterials disputes the allocatio