FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT

This FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT, dated as of August 3, 2012 (this “Amendment”), is entered into by and among Summit Midstream Holdings, LLC (the “Borrower”), The Royal Bank of Scotland plc (“RBS”), as the Administrative Agent (the “Administrative Agent”), and the Required Lenders party hereto. Capitalized terms used herein and not otherwise defined herein shall have the meanings given to them in the Credit Agreement (as defined below).

WHEREAS, the parties hereto are parties to that certain Amended and Restated Credit Agreement, dated as of May 7, 2012 (as the same may from time to time be amended, amended and restated, supplemented or otherwise modified, the “Credit Agreement”), by and among the Borrower, the Administrative Agent, RBS, as the Collateral Agent, RBS and Bank of America, N.A. as Issuing Banks, the lenders party thereto (the “Lenders”), and the other agents party thereto;

WHEREAS, Borrower desires to amend the Credit Agreement to clarify the treatment of deferred revenue of Borrower and its Restricted Subsidiaries thereunder, and, in connection therewith, has requested that the Required Lenders agree to the amendment to the Credit Agreement set forth herein on the terms and conditions set forth herein; and

WHEREAS, the Required Lenders are willing to agree to such amendment, on the terms and conditions set forth herein.

NOW, THEREFORE, in consideration of the promises and covenants set forth herein and for other good and valuable consideration, the receipt of which is hereby acknowledged, the parties hereto, intending to be legally bound hereby, agree as follows:

A new clause (k) is hereby added to the end of the definition of “Consolidated Net Income” in Section 1.01 of the Credit Agreement, reading in its entirety as follows:

(k)     Consolidated Net Income for such period shall be increased to the extent of any increase in the amount of deferred revenue for such period (as compared with the preceding period), and decreased to the extent of any decrease in the amount of deferred revenue for such period (as compared with the preceding period).

(a) This Amendment shall become effective as of the date on which each of the following conditions precedent shall have been satisfied (the “First Amendment Effective Date”): (a) the Administrative Agent shall have received this Amendment, duly executed by the Borrower and the Required Lenders; (b) the representations and warranties contained in Article III of the Credit Agreement shall be true and correct in all material respects, except to the extent that such representations and warranties specifically refer to an earlier date, in which case they shall have been true and correct in all material respects as of such earlier date; (c) as of the First Amendment Effective Date (and after giving effect to this Amendment), no Default or Event of Default shall have occurred and be continuing; and (d) the Borrower shall have paid all fees and expenses then due and payable to the Lenders and the

Administrative Agent hereunder or under any other Loan Document, including as set forth in Section 3 hereof; provided, however, that (i) for purposes of the Credit Agreement, as of the First Amendment Effective Date, the amendment set forth in Section 1 shall be deemed to be effective as of the last date of fiscal quarter of the Borrower that ended on March 31, 2012, and each fiscal quarter thereafter, and (ii) together with the financial statements delivered by the Borrower pursuant to Section 5.04(b) of the Credit Agreement in respect of the fiscal quarter that ended on June 30, 2012, the Borrower shall deliver to the Administrative Agent revised financial statements for the fiscal quarter that ended on March 31, 2012, revised to reflect the amendment set forth in Section 1.

(b)     Notwithstanding the foregoing, this Amendment shall not become effective and the agreements hereunder will be terminated unless each of the foregoing conditions is satisfied (or waived by Lenders comprising at least the Required Lenders in writing) on or prior to August 31, 2012.

The Borrower agrees to pay on demand in accordance with the terms of Section 9.05(iii) of the Credit Agreement all reasonable and documented out-of-pocket expenses incurred by the Administrative Agent and its Affiliates in connection with the preparation of this Amendment.

(a)    This Amendment shall be construed as an amendment to the Credit Agreement and shall be administered and applied in accordance with the terms and provisions thereof.

(b)    Except as specifically amended pursuant to the terms of this Amendment, the terms and conditions of the Credit Agreement and the other Loan Documents remain in full force and effect and are hereby ratified and confirmed.

(c)    The amendment set forth herein is limited strictly to its terms, and shall not operate as a modification or waiver of any right, power or remedy of the Lenders, the Borrower, the Administrative Agent or any other Person under the Credit Agreement or any other Loan Document, nor constitute a modification or waiver of any other provision of the Credit Agreement or any other Loan Document.

(d)    Each of the Loan Documents, including the Credit Agreement, and any and all other agreements, documents or instruments now or hereafter executed or delivered pursuant to the terms hereof or pursuant to the terms of the Credit Agreement as amended hereby, are hereby amended so that any reference in such Loan Documents to the Credit Agreement, whether direct or indirect, shall mean a reference to the Credit Agreement as amended hereby.

(e)    The Borrower and each other Loan Party hereby ratifies, approves and confirms in every respect all the terms, provisions, conditions and obligations of the Credit Agreement and each of the other Loan Documents, including without limitation all Mortgages, the Collateral Agreement and other Collateral Documents, to which it is a party.

The Borrower hereby represents and warrants that after giving effect hereto:

(a)    the execution, delivery and performance by the Borrower and each other Loan Party of this Amendment and the other Loan Documents have been duly authorized by all necessary corporate or other action required on their part and this Amendment, along with the Credit Agreement and other Loan

Documents, constitutes the legal, valid and binding obligation of each Loan Party party thereto enforceable against them in accordance with its terms, except as its enforceability may be affected by the effect of bankruptcy, insolvency, reorganization, moratorium or other similar laws now or hereafter in effect relating to or affecting the rights or remedies of creditors generally; and

(b)    neither the execution, delivery and performance of this Amendment by the Borrower and each other Loan Party, the performance by them of the Credit Agreement nor the consummation of the transactions contemplated hereby does or shall contravene, result in a breach of, or violate (i) any provision of any Loan Party’s certificate or articles of incorporation or bylaws or other similar documents, or agreements, (ii) any law or regulation, or any order or decree of any court or government instrumentality, or (iii) any indenture, mortgage, deed of trust, lease, agreement or other instrument to which any Loan Party is a party or by which any Loan Party or any of their property is bound, except in any such case to the extent such conflict or breach has been waived by a written waiver document, a copy of which has been delivered to Administrative Agent on or before the date hereof.

(a)    THIS AMENDMENT SHALL BE CONSTRUED IN ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

(b)    This Amendment may be executed in one or more counterparts, each of which shall constitute an original but all of which, when taken together, shall constitute but one contract, and shall become effective as provided in Section 2 hereof. Delivery of an executed counterpart to this Amendment by facsimile transmission or an electronic transmission of a PDF copy thereof shall be as effective as delivery of a manually signed original. Any such delivery shall be followed promptly by delivery of the manually signed original.

(c)    In the event any one or more of the provisions contained in this Amendment should be held invalid, illegal or unenforceable in any respect, the validity, legality and enforceability of the remaining provisions contained herein and therein shall not in any way be affected or impaired thereby. The parties hereto shall endeavor in good-faith negotiations to replace the invalid, illegal or unenforceable provisions with valid provisions the economic effect of which comes as close as possible to that of the invalid, illegal or unenforceable provisions.

(d)    The terms of this Amendment shall be binding upon, and shall inure to the benefit of, the parties hereto and their respective successors and permitted assigns.

(e)    This Amendment is a Loan Document.