AMENDMENT NO. 2 TO REVOLVING CREDIT AND TERM LOAN AGREEMENT

Exhibit 10.1

EXECUTION COPY

AMENDMENT NO. 2 TO

REVOLVING CREDIT AND TERM LOAN AGREEMENT

This Amendment No. 2 dated as of May 29, 2009 to the Revolving Credit and Term Loan Agreement (this “ Amendment No. 2 ”), is entered into among Atlas Pipeline Partners, L.P., a Delaware limited partnership (“ Borrower ”), the Subsidiaries of the Borrower identified as “Guarantors” on the signature pages hereto (the “ Guarantors ”), the Lenders signatory hereto and Wachovia Bank, National Association, in its capacity as administrative agent for the Lenders (in such capacity, the “ Administrative Agent ”) and amends the Revolving Credit and Term Loan Agreement dated as of July 27, 2007 (as amended by Amendment No. 1 and Agreement dated as of June 12, 2008 and as amended, supplemented or otherwise modified from time to time, the “ Credit Agreement ”) entered into among the Borrower, the Guarantors named therein, the institutions from time to time party thereto as Lenders (the “ Lenders ”), the Administrative Agent and the other agents and arrangers named therein. Capitalized terms used herein and not otherwise defined herein shall have the meanings ascribed to them in the Credit Agreement.

W I T N E S S E T H:

WHEREAS, Section 12.04 of the Credit Agreement provides that the Credit Agreement may be amended, modified and waived from time to time;

WHEREAS, the Borrower and Atlas Pipeline Operating Partnership, L.P. (“ APL Operating ”) have entered into a Formation and Exchange Agreement dated as of March 31, 2009 by and between Williams Field Services Group, LLC (“ WFSG ”), Williams Laurel Mountain, the Borrower, APL Operating and APL Laurel Mountain, LLC providing for contribution by the Borrower to Laurel Mountain Midstream, LLC, a Delaware limited liability company (“ Laurel Mountain ”), the joint venture formed by the Borrower and WFSG of the natural gas gathering and transportation business and the natural gas liquids extraction business conducted utilizing the natural gas gathering system located in eastern Ohio, western New York, northern West Virginia and western Pennsylvania and the liquids extraction facility located in McKean County, Pennsylvania (the “ Appalachian Business ”), in exchange for a cash payment to a subsidiary of the Borrower of $90 million and the issuance to such subsidiary of the Borrower of (x) a 49% interest in Laurel Mountain and (y) preferred distribution rights with respect to payments made by WFSG or a subsidiary thereof on account of the $25.5 million promissory note to be issued by such subsidiary of WFSG and guaranteed by WSFG to Laurel Mountain as part of WFSG’s capital contribution to Laurel Mountain (the “ LM Preferred Interest ”);

WHEREAS, the Borrower desires to amend the Credit Agreement to permit the sale of the Appalachian Business to Laurel Mountain;

WHEREAS, the Borrower has requested that the Administrative Agent and the Lenders agree to amend the Credit Agreement in certain other respects as set forth herein;

WHEREAS, subject to certain conditions, the Required Lenders are willing to agree to the amendments set forth in Section 1 hereof relating to the Credit Agreement;

NOW, THEREFORE, in consideration of the premises and for other good and valuable consideration (the receipt and sufficiency of which are hereby acknowledged), the parties hereto hereby agree as follows:

Section 1. Amendment to Credit Agreement

(a) Amendments to Section 1.02 of the Credit Agreement . Section 1.02 of the Credit Agreement is hereby amended as follows:

(i) The definition of “ Adjusted LIBOR ” is hereby amended by inserting the following immediately after “Interest Period” and immediately prior to “.”:

; provided that notwithstanding the foregoing, if the Adjusted LIBOR Rate for any Interest Period as so calculated shall be less than 2.00% per annum, the Adjusted LIBOR Rate shall be deemed to be 2.00% per annum.”

(ii) The definition of “ Applicable Margin ” is hereby amended and restated as follows:

“ Applicable Margin means (i) prior to the Amendment No. 2 Effective Date, “Applicable Margin as defined in this Agreement prior to giving effect to Amendment No. 2 and (ii) on and after the Amendment No. 2 Effective Date, with respect to Term Loans and Revolver Loans, (x) if the Leverage Ratio is less than 7.0 to 1, 4.75% for LIBOR Loans and 3.75% for Base Rate Loans and (y) if otherwise, 5.75% for LIBOR Loans and 4.75% for Base Rate Loans.”

(iii) The definition of “ Commitment Fee Percentage ” is hereby amended and restated as follows:

“ Commitment Fee Percentage means (i) prior to the Amendment No. 2 Effective Date, shall mean “Commitment Fee Percentage” as defined in this Agreement prior to giving effect to Amendment No. 2 and (ii) on and after the Amendment No. 2 Effective Date, 0.50%”

(iv) The definition of “ Consolidated EBITDA ” is hereby amended and restated as follows (with changes highlighted by underlining insertions and strikethrough text to mark deletions):

“ Consolidated EBITDA means, for any trailing twelve-month period, the sum of (i) Consolidated Net Income for such period, plus without duplication (ii) the following expenses or charges to the extent deducted from Consolidated Net Income in such period: interest, income taxes, depreciation, depletion, amortization, non-cash compensation on long-term incentive plans, extraordinary, unusual or non-recurring charges relating to premiums or penalties paid to counterparties, in connection with the breakage, termination or unwinding of Hedging Agreements to the extent such charges are financed with or paid for out of proceeds of an Equity Offering by the Borrower and other non-cash charges (other than a non-cash charge resulting from an accrual of a reserve for any cash charge in any future period) to Consolidated Net Income including non-cash losses resulting from mark to market accounting of Hedging Agreements, plus without duplication (iii) the amount of dividends or distributions (other than a LM Preferred Interest Distribution Setoff) received in cash by the Borrower and its Consolidated Subsidiaries from Laurel Mountain, minus without duplication (iv) non-cash credits to Consolidated Net Income including non cash gains resulting from mark to market accounting of Hedging Agreements. For purposes of this Agreement, Consolidated EBITDA shall be adjusted on a pro forma basis, in a manner reasonably acceptable to the Administrative Agent, to include, as of the first day of any applicable period, the historical financial results of any acquisition permitted by Section 9.03(i) closed during such period and exclude, as of the first day of any applicable period, without duplication,

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the Consolidated EBITDA attributable to (i) assets divested by the Borrower; (ii) to the extent funded with the Net Cash Proceeds from an Equity Offering, losses (in an amount not to exceed the Net Cash Proceeds from such Equity Offering) resulting from the termination or unwinding of Hedging Agreements of the type described in Section 9.07(a) and (iii) the after-tax effect of income (loss) from the early extinguishment of and the interest payments made on Debt extinguished, in each case, occurring during such period or subsequent thereto but on or prior to the date of determination of Consolidated EBITDA; provided that the Consolidated EBITDA attributable to (I) the Appalachian Business; the NOARK Entities and the Sweetwater Gas Processing Plant located in Beckham County, Oklahoma, (II) termination or unwinding prior to March 31, 2009 of Hedging Agreements of the type described in Section 9.07(a) and (III) the after-tax effect of income (loss) from the early extinguishment of Debt prior to March 31, 2009 shall be included.”

(v) The definition of “ Consolidated Interest Expense ” is hereby amended and restated as follows (with changes highlighted by underlining insertions and strikethrough text to mark deletions):

Consolidated Interest Expense means with respect to such Person and its Consolidated Subsidiaries, for any period, the aggregate cash interest payments made or required to be made for such Person and its Consolidated Subsidiaries on a consolidated basis for such period; provided , that (i) Consolidated Interest Expense for the fiscal quarter ending December 31, 2007 shall be calculated by annualizing the Consolidated Interest Expense for such fiscal quarter, (ii) Consolidated Interest Expense for the fiscal quarter ending March 31, 2008 shall be calculated by annualizing the Consolidated Interest Expense for such fiscal quarter and the previous fiscal quarter; (iii) Consolidated Interest Expense for fiscal quarter ending June 30, 2008 shall be calculated by annualizing the Consolidated Interest Expense for such fiscal quarter and the two (2) previous fiscal quarters and (iv) Consolidated Interest Expense shall exclude historical cash interest payments made with respect to Loans that are prepaid in such period with the Net Cash Proceeds of a Disposition permitted under Section 9.17(f) ; provided that Consolidated Interest Expense for the fiscal quarter ended March 31, 2009 and the fiscal quarter ended June 30, 2009 shall include historical cash interest payments made with respect to Loans that were prepaid with the Net Cash Proceeds of the Dispositions of the Appalachian Business; the NOARK Entities and the Sweetwater Gas Processing Plant located in Beckham County, Oklahoma.

(vi) The definition of “ Debt ” is hereby amended by inserting the following at the end of clause (v) immediately after “such Property” and before “;”:

“excluding however (y) oil and gas leases or rights of way acquired in the ordinary course of business solely with respect to the right to maintain flow lines or gathering lines or sales lines across the lands subject thereto, and (z) equipment leases in the ordinary course of business for (i) gathering and processing of Hydrocarbons gathered and transported through the Pipelines or processed, treated or handled in the Pipeline Properties and (ii) office equipment, in each case to the extent such leases are properly accounted for under GAAP as operating leases and not capital leases or as part of a sale leaseback transaction.”

(vii) The definition of “ Increase Effective Date ” is hereby deleted in its entirety.

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(viii) The definition of “ Incremental Loan ” is hereby deleted in its entirety.

(ix) The definition of “ Incremental Loan Commitment ” is hereby deleted in its entirety

(x) The definition of “ Incremental Loan Maturity Date ” is hereby deleted in its entirety.

(xi) The definition of “ Increase Joinder ” is hereby deleted in its entirety

(xii) The definition of “ Mortgages ” is hereby amended and restated as follows:

“ Mortgages ” means each of the Open-Ended Mortgages described or referred to in Exhibit D hereto and any additional mortgages, deeds of trust, security agreements and financing statements or other Security Instruments necessary and appropriate to create and perfect a mortgage Lien in any additional Pipeline Properties acquired by any Obligor as contemplated by Section 8.09(a) hereof”.

(xiii) The definition of “ Pro Forma Cost Savings ” is hereby deleted in its entirety.

(xiv) The definition of “ Revolver Facility ” is hereby amended by deleting the words “or increased pursuant to Section 2.12(a).”

(xv) The definition of “ Specified Acquisition Period ” is hereby deleted in its entirety.

(xvi) The following definitions shall be added in alphabetical order to read as follows:

AHD Preferred Equity Investment shall mean the Class B Member Interest issued by a wholly-owned subsidiary of Atlas Pipeline Holdings, L.P. to the Borrower in exchange for cash consideration of $15 million.

Amendment No. 2 shall mean that certain Amendment No. 2 to the Credit Agreement dated as of the Amendment No. 2 Effective Date among the Borrower, the Guarantors, the Lenders and Administrative Agent.

Amendment No. 2 Effective Date shall mean the date on which each of the conditions precedent to the effectiveness of Amendment No. 2 shall have been satisfied or waived by the Administrative Agent.

Appalachian Business has the meaning given to such term in the Laurel Mountain Formation and Exchange Agreement.

Appalachian Business Investment means the acquisition by the Borrower and its Consolidated Subsidiaries of (x) a 49% interest in Laurel Mountain and (y) the LM Preferred Interest as part of the consideration in exchange for the contribution by the Borrower and its Consolidated Subsidiaries of the Appalachian Business to Laurel Mountain.

Appalachian Disposition means the sale of the Appalachian Business.

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Available Cash shall mean, as at any date of determination, the total amount classified as cash and cash equivalents on a consolidated balance sheet of the Borrower and its Consolidated Subsidiaries in accordance with GAAP less amounts classified as restricted cash.

Capital Assets shall mean, with respect to any person, all equipment, fixed assets and real Property or improvements of such Person, or replacements or substitutions therefor or additions thereto, that, in accordance with GAAP, have been or should be reflected as additions to property, plant or equipment on the balance sheet of such Person.

Capital Expenditures shall mean, for any period, without duplication, all expenditures (including, without limitation, expenditures related to maintenance and repairs) made directly or indirectly by the Borrower and its Subsidiaries during such period for Capital Assets (whether paid in cash or other consideration or financed by the incurrence of Debt), but excluding (i) any portion of the increase in Capital Assets attributable solely to acquisitions of property, plant and equipment permitted by Section 9.03(i) ; (ii) the Appalachian Business Investment, (iii) additional investments by the Borrower and its Consolidated Subsidiaries permitted by Section 9.03(g)(ii) , and (iv) any LM Preferred Interest Distribution Setoff amounts.

Consolidated Senior Secured Funded Debt shall mean, as at any date of determination, Consolidated Funded Debt that is not Subordinated Debt and that is secured by a Lien on any assets of the Borrower or any of its Subsidiaries.

Excess Cash Flow means, for any Excess Cash Flow Period, the sum of the following determined on a consolidated basis, without duplication, for the Borrower and its Consolidated Subsidiaries in accordance with GAAP: (a) Consolidated EBITDA for such period minus (b) the sum of the following: (i) cash taxes and Consolidated Interest Expense paid in cash for such period, (ii) the cash amount of all permitted principal payments made in respect of Debt during such period, (iii) all Capital Expenditures made during such period, (iv) the cash amount of all permitted principal payments made with respect to the Term Loan Facility and prepayments or repayments of the Revolver Loans to the extent that the Revolver Commitment is permanently reduced by an equal amount at the time of such payment, (v) the cash portion of the purchase price and other reasonable acquisition-related costs paid by the Borrower for acquisitions permitted by Section 9.03(i) , (vi) Transaction Costs during such period, (vii) transaction costs and premiums paid to purchase options permitted under Section 9.07 and (viii) investments permitted by Section 9.03(g) (other than investments made with the LM Preferred Interest Distribution Setoff) and (p)  plus or minus (c) any increases or decreases in working capital.

Excess Cash Flow Period shall mean (i) the period taken as one accounting period from and including July 1, 2009 and ending on December 31, 2009 and (ii) each fiscal year of Borrower thereafter.

Laurel Mountain means the joint venture formed by the Borrower and WFSG pursuant to the Laurel Mountain Formation and Exchange Agreement.

Laurel Mountain Formation and Exchange Agreement means that certain Formation and Exchange Agreement entered into as of March 31, 2009 by and between WFSG, Williams Laurel Mountain, LLC, the Borrower, APL Operating and APL Laurel Mountain, LLC, as amended by Amendment No. 1 dated as of April 16, 2009.

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Laurel Mountain LLC Agreement means that certain Amended and Restated Limited Liability Company Agreement of Laurel Mountain by and between Williams Laurel Mountain, LLC and APL Laurel Mountain, LLC to be entered into upon the sale of the Appalachian Business.

LM Preferred Interest means the preferred distribution rights with respect to payments made by WFSG or a subsidiary thereof on account of the WFSG Promissory Note issued to Laurel Mountain as part of WFSG’s capital contribution to Laurel Mountain.

LM Preferred Interest Distribution Setoff means any dividend, distribution, cancellation, contribution of or setoff with respect to the LM Preferred Interest that is applied to the payment of capital contributions otherwise payable by the Borrower or any of its Consolidated Subsidiaries to Laurel Mountain.

Minimum Liquidity shall mean, as at any date of determination, the sum of Available Cash and, so long as at any such date of determination the conditions precedent set forth in Section 6.02 are satisfied, the Revolver Availability Amount.

NOARK Entities means Atlas Arkansas, AAPL2, NOARK, OGG and OGT.

Revolver Availability Amount shall mean, as at any date of determination, the excess of the aggregate of Revolver Commitments of Revolver Lenders over the aggregate Revolver Principal Debt of Revolver Lenders.

Senior Secured Leverage Ratio has the meaning given to such term in Section 9.12 .

Specified Debt shall mean Subordinated Debt and any senior or subordinated unsecured notes.

Transaction Costs means all transaction fees, charges and other amounts related to this Agreement and any future amendments hereof or any acquisition permitted by Section 9.03(i) or, to the extent paid to non-Affiliates, any permitted Disposition (including, without limitation, any financing fees, merger and acquisition fees, legal fees and expenses, due diligence fees or any other fees and expenses in connection therewith), all such transaction fees as approved by the Administrative Agent, such approval not to be unreasonably withheld.

WFSG means Williams Field Services Group, LLC.

WFSG Promissory Note means that certain $25.5 million promissory note issued by a subsidiary of WFSG to Laurel Mountain and guaranteed by WFSG as part of the consideration in exchange for the contribution by the Borrower and its Consolidated Subsidiaries of the Appalachian Business to Laurel Mountain.

(b) Section 2.04(a) of the Credit Agreement is hereby amended to delete the final two sentences thereof.

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(c) Section 2.12 of the Credit Agreement is hereby deleted in its entirety; provided that it is understood and agreed that such deletion shall not affect the Revolving Commitments outstanding immediately prior to the Amendment No. 2 Effective Date (for avoidance of doubt, such Revolving Commitments include the Incremental Loan Commitments that were provided by the Lenders party to the Increase Joinder dated June 27, 2008 among the Borrower, the Administrative Agent and such Lenders).

(d) Section 3.01(b)(iii) is hereby amended by deleting it in its entirety and replacing with the following (with changes highlighted by underlining insertions and strikethrough text to mark deletions):

“(iii) The Borrower shall prepay the Loans in the manner set forth in clause (vi) below in amounts equal to with respect to any Equity Offering consummated, commenced or announced after March 31, 2009, (x) on or prior to September 30, 2009, fifty percent (50%) and (y) thereafter, fifty percent (50%) (or if the Borrower’s Leverage Ratio is less than 5.0:1.0, 0%) of the aggregate Net Cash Proceeds from any Equity Offering by or capital contribution to the Borrower or any of its Subsidiaries other than the exercise price on stock options issued as part of employee compensation. Such prepayment shall be made within five (5) Business Days after the date of receipt of Net Cash Proceeds of any such transaction.”

(e) Section 3.01(b)(iv) of the Credit Agreement is hereby amended by deleting it in its entirety and replacing with the following (with changes highlighted by underlining insertions and strikethrough text to mark deletions):

“(iv) The Borrower shall prepay the Loans in the manner set forth in clause (vi) below in amounts equal to one hundred percent (100%) of the aggregate Net Cash Proceeds from any Disposition by the Borrower or any of its Subsidiaries. Such prepayments shall be made within five (5) Business Days after receipt of Net Cash Proceeds of any such transaction by the Borrower or any of its Subsidiaries; provided that, so long as no Default or Event of Default has occurred and is continuing, no prepayments shall be required hereunder (A) in connection with (x) up to $135,000,000 of aggregate Net Cash Proceeds in respect of Dispositions consummated in the fiscal year ended December 31, 2009 and (y) up to $50,000,000 of aggregate Net Cash Proceeds in respect of Dispositions consummated in any fiscal year thereafter from Dispositions (other than any Disposition pursuant to the terms of the Pioneer Option Agreement) by the Borrower or any of its Subsidiaries which is reinvested within three hundred sixty (360) days after receipt of such Net Cash Proceeds by the Borrower or any of its Subsidiaries in similar replacement assets; provided that such $50,000,000 basket in this clause (y) shall not apply with respect to any Disposition if pro forma for any such Disposition, (A) the Senior Secured Leverage Ratio would be greater than 3.00 to 1.00 or (B) the Minimum Liquidity would be less than or equal to $50 million, in which case the Borrower shall be required to prepay the Loans in the manner set forth in clause (vi) below in amounts equal to one hundred percent (100%) of the aggregate Net Cash Proceeds from any such Disposition by the Borrower or any of its Subsidiaries or (B) in connection with Dispositions permitted pursuant to Section 9.17 (other than Section 9.17(f) ).”

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(f) Section 3.01(b) is hereby amended by inserting the following clause (viii) as follows:

“(viii) No later than five Business Days after the date on which the financial statements with respect to each Excess Cash Flow Period are or are required to be delivered pursuant to Section 8.01(a) (without giving effect to any grace period applicable thereto), the Borrower shall promptly deliver a notice of prepayment to the Administrative Agent and upon receipt of such notice, the Administrative Agent shall promptly so notify the Lenders. Each prepayment of the Loans under this clause (viii) shall be applied in the manner set forth in clause (vi) above and in accordance with the provisions of Section 2.07 in an aggregate amount equal to the applicable percentage set forth at the appropriate intersection in the table set forth below, based on the Leverage Ratio as in effect from time to time:

provided that, notwithstanding the provisions of Section 2.07, Revolver Loans required to be repaid with Excess Cash Flow pursuant to this clause (viii) shall not be available to be reborrowed and the Revolver Commitment shall be permanently reduced by the amount of such payment applied to repay Revolver Loans.”

(g) Section 7.23 of the Credit Agreement is hereby amended by inserting the words “the agreements relating to Laurel Mountain, including, without limitation, the Laurel Mountain LLC Agreement and the Laurel Mountain Formation and Exchange Agreement and” immediately after “(“ and immediately preceding the words “the agreements referenced.”

(h) Section 8.07 of the Credit Agreement is hereby amended by deleting the words “Reserved” and replacing them with the following:

“Section 8.07 Capital Expenditures and Hedging Strategy Consultant . No later than 45 days after the Amendment No. 2 Effective Date, the Borrower shall engage, at the Borrower’s expense, a consultant reasonably acceptable to the Borrower and the Administrative Agent to conduct a one-time review reasonably satisfactory in scope to the Administrative Agent of the Capital Expenditures strategy and the Hedging Agreements strategy of the Borrower and its Consolidated Subsidiaries. Such consultant shall deliver their report with respect to such review to the Borrower and to the Administrative Agent. The Administrative Agent shall make such report available to the Lenders as soon