GUARANTY

Exhibit 10.41

GUARANTY

     THIS GUARANTY (this “ Guaranty ”), dated as of February 21, 2008, is made by the undersigned (the “ Guarantor ”), in favor of ROYAL BANK OF CANADA, as administrative agent for the Lenders (as defined below).

W I T N E S S E T H :

     WHEREAS, pursuant to that certain Amended and Restated Credit Agreement dated November 1, 2007 (as the same may hereafter be amended, supplemented and restated, the “ Credit Agreement ”), among Quest Midstream Partners, L.P., a Delaware limited partnership (“ MLP ”) and Bluestem Pipeline, LLC, a Delaware limited liability company (“ Bluestem ” and together with MLP, collectively, the " Borrowers ”), the various financial institutions that are, or may from time to time become, parties thereto (individually a “ Lender ” and collectively the “ Lenders ”) and Royal Bank of Canada, as administrative agent and collateral agent (in its capacity as administrative agent, the “ Administrative Agent ”), the Lenders have agreed to make Credit Extensions for the account of the Borrowers; and

     WHEREAS, the Borrowers have covenanted in Section 6.14 of the Credit Agreement within thirty (30) days after the formation or acquisition of any Subsidiary to cause such Subsidiary to execute a Guaranty and Collateral Documents; and

     WHEREAS, Guarantor was formed by the MLP on January 23, 2008 and is required to execute and deliver this Guaranty; and

     WHEREAS, Guarantor has duly authorized the execution, delivery and performance of this Guaranty; and

     WHEREAS, Guarantor is a wholly owned direct or indirect subsidiary of the MLP; and

     WHEREAS, it is in the best interests of Guarantor to execute this Guaranty inasmuch as Guarantor will derive substantial direct and indirect benefits from the extensions of credit made from time to time to or for the account of the Borrowers.

     NOW THEREFORE, for good and valuable consideration, the receipt of which is hereby acknowledged, and in order to induce the Lenders to make Credit Extensions to the Borrower pursuant to the Credit Agreement by fulfilling the requirements of the Credit Agreement, Guarantor agrees, for the benefit of each Lender, as follows:

ARTICLE I

DEFINITIONS

      SECTION 1.1 Certain Terms . The following capitalized terms when used in this Guaranty, including its preamble and recitals, shall have the following meanings (such definitions to be equally applicable to the singular and plural forms thereof):

     “ Administrative Agent ” is defined in the first recital.

     “ Borrowers ” is defined in the first recital.

     “ Commitments ” means each Commitment as defined in the Credit Agreement.

     “ Credit Extensions ” means each Credit Extension as defined in the Credit Agreement.

     “ Guarantor ” is defined in the preamble.

     “ Guaranty ” is defined in the preamble.

     “ Lenders ” is defined in the first recital.

     “ Loan Documents ” means the Loan Documents as defined in the Credit Agreement.

     “ Note ” means each Revolving Note as defined in the Credit Agreement.

     “ Obligations ” means the Obligations as defined in the Credit Agreement.

     “ Obligor ” means the Borrowers or any other Person (other than the Administrative Agent or any Lender) obligated under any Loan Document.

     “ Required Lenders ” means the Required Lenders as defined in the Credit Agreement.

     “ Taxes ” is defined in clause (a) of Section 2. 7.

     “ UCC ” means the Uniform Commercial Code as in effect in the State of New York.

      SECTION 1.2 Credit Agreement Definitions . Unless otherwise defined herein or the context otherwise requires, capitalized terms used in this Guaranty, including its preamble and recitals, have the meanings provided in the Credit Agreement,

      SECTION 1.3 UCC Definitions . Unless otherwise defined herein or the context otherwise requires, terms for which meanings are provided in the UCC are used in this Guaranty, including its preamble and recitals, with such meanings.

ARTICLE II

GUARANTY PROVISIONS

      SECTION 2.1 Guaranty . Guarantor hereby absolutely, unconditionally, and irrevocably (1) guarantees the full and punctual payment when due, whether at stated maturity, by required prepayment, declaration, acceleration, demand or otherwise, of all Obligations of the Borrowers and each other Obligor now or hereafter existing under each of the Credit Agreement, the Notes and each other Loan Document to which the Borrowers or such other Obligor is or may become a party, whether for principal, interest, fees, expenses or otherwise (including all such amounts which would become due but for the operation of the automatic stay under Section 362(a) of the United States Bankruptcy Code, 11 U.S.C. §362(a), and the operation of Sections 502(b) and 506(b) of the United States Bankruptcy Code, 11 U.S.C. §502(b) and §506(b)), and (2) indemnifies and holds harmless each Lender and each holder of a Note for any and all costs and expenses (including reasonable attorney’s fees and expenses) incurred by such Lender or such holder, as the case may be, in enforcing any rights under this Guaranty; provided however, that Guarantor shall be liable under this Guaranty for the maximum amount of such liability that can be hereby incurred without rendering this Guaranty, as it relates to Guarantor, voidable under applicable law relating to fraudulent conveyance or fraudulent transfer, and not for any greater amount.

This Guaranty constitutes a guaranty of payment when due and not of collection, and Guarantor specifically agrees that it shall not be necessary or required that any Lender or any holder of any Note exercise any right, assert any claim or demand or enforce any remedy whatsoever against the Borrowers or any other Obligor (or any other Person) before or as a condition to the obligations of Guarantor hereunder.

      SECTION 2.2 Acceleration of Guaranty . Guarantor agrees that, in the event of the occurrence of any event of the type described in Section 8.01(f) of the Credit Agreement, with respect to the Borrowers, any other Obligor or any other Guarantor, and if such event shall occur at a time when any of the Obligations may not then be due and payable, Guarantor will pay to the Lenders forthwith the full amount which would be payable hereunder by Guarantor if all such Obligations were then due and payable.

      SECTION 2.3 Guaranty Absolute, etc . This Guaranty shall in all respects be a continuing, absolute, unconditional and irrevocable guaranty of payment, and shall remain in full force and effect until all Obligations (other than contingent indemnity obligations) of the Borrowers and each other Obligor have been paid in full (or, in the case of L/C Obligations, Cash Collateralized), all obligations of Guarantor hereunder shall have been paid in full, all Commitments shall have terminated and, except as provided in Section 10.01(e) of the Credit Agreement, all Lender Hedging Agreements have terminated. Guarantor may not rescind or revoke its obligations hereunder. Guarantor guarantees that the Obligations of the Borrowers and each other Obligor will be paid strictly in accordance with the terms of the Credit Agreement and each other Loan Document under which they arise, regardless of any law, regulation or order now or hereafter in effect in any jurisdiction affecting any of such terms or the rights of any Lender or any holder of any Note with respect thereto. The liability of Guarantor under this Guaranty shall be absolute, unconditional and irrevocable irrespective of: (1) any lack of validity, legality or enforceability of the Credit Agreement, any Note or any other Loan Document; (2) the failure of any Lender or any holder of any Note (a) to assert any claim or demand or to enforce any right or remedy against the Borrowers, any other Obligor or any other Person (including any other Guarantor) under the provisions of the Credit Agreement, any Note, any other Loan Document or otherwise, or (b) to exercise any right or remedy against any other Guarantor of, or collateral securing, any Obligations of the Borrowers or any other Obligor; (3) any change in the time, manner or place of payment of, or in any other term of, all or any of the Obligations of the Borrowers or any other Obligor, or any other extension, compromise or renewal of any Obligations of the Borrowers or any other Obligor; (4) any reduction, limitation, impairment or termination of any Obligations of the Borrowers or any other Obligor for any reason, including any claim of waiver, release, surrender, alteration or compromise, and shall not be subject to (and Guarantor hereby waives any right to or claim of) any defense or setoff, counterclaim, recoupment or termination whatsoever by reason of the invalidity, illegality, nongenuineness, irregularity, compromise, unenforceability of, or any other event or occurrence affecting, any Obligations of the Borrowers, any other Obligor or otherwise; (5) any amendment to, rescission, waiver, or other modification of, or any consent to departure from, any of the terms of the Credit Agreement, any Note or any other Loan Document; (6) any addition, exchange, release, surrender or non-perfection of any collateral, or any amendment to or waiver or release or addition of, or consent to departure from, any other guaranty, held by any Lender or any holder of any Note securing any of the Obligations of the Borrowers or any other Obligor; (7) the insolvency or bankruptcy of, or similar event affecting, the Borrowers or any other Obligor; or (8) any other circumstance which might otherwise constitute a defense available to, or a legal or equitable discharge of, the Borrowers, any other Obligor, any surety or any guarantor. Guarantor waives all rights and defenses which may arise with respect to any of the foregoing, and Guarantor waives any right to revoke this Guaranty with respect to future indebtedness.

      SECTION 2.4 Reinstatement . Guarantor agrees that this Guaranty shall continue to be effective or be reinstated, as the case may be, if at any time any payment (in whole or in part) of any of the Obligations is rescinded or must otherwise be restored by any Lender or any holder of any Note, upon the insolvency, bankruptcy or reorganization of either Borrower, any other Obligor or otherwise, all as though such payment had not been made.

      SECTION 2.5 Waiver, etc. Guarantor hereby waives promptness, diligence, notice of acceptance and an