AGREEMENT FOR PURCHASE AND SALE OF OF MEMBERSHIP INTEREST

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THIS AGREEMENT FOR PURCHASE AND SALE OF MEMBERSHIP INTEREST (this “ Agreement ”) is executed as of this 19 ^th day of May, 2009 by and between GAS TRANSMISSION NORTHWEST CORPORATION, a California corporation (“ Seller ”), and TC PipeLines Intermediate Limited Partnership, a Delaware limited partnership (“ Buyer ”).  Seller and Buyer are sometimes referred to herein individually as a “ Party ” and collectively as the “ Parties .”

WHEREAS, Seller owns a 100% membership interest (the “ Seller LLC Interest ”) in North Baja Pipeline, LLC, a Delaware limited liability company (“ NBLLC ”), and is a party to that Limited Liability Company Agreement, dated as of October 24, 2000, as amended by the Amendment to Limited Liability Company Agreement, dated January 31, 2005 (collectively, the “ NBLLC Agreement ”);

WHEREAS, Buyer desires to purchase and acquire, and Seller desires to sell and assign, the Seller LLC Interest pursuant to the terms and conditions set forth in this Agreement; and

WHEREAS, the sale of the Seller LLC Interest pursuant to this Agreement is part of, and coincident with the completion of, another transaction that includes the exchange by TC PipeLines GP, Inc., a Delaware corporation and an Affiliate of Seller, of certain incentive distribution rights available to it under the Amended and Restated Agreement of Limited Partnership of TC PipeLines, LP, a Delaware limited partnership and an Affiliate of Buyer (“ Limited Partnership ”), for common units of Limited Partnership and revised distribution rights (the “ IDR Transaction ”) and the subscription by TransCan Northern Ltd., a Delaware corporation, for certain common units of Limited Partnership.

NOW, THEREFORE, in consideration of the premises and the mutual covenants herein contained, and for other good and valuable consideration, the receipt and adequacy of which is hereby acknowledged, the Parties, intending to be legally bound, hereby agree as follows:

     Section 1.01       Agreement to Sell and to Purchase Seller LLC Interest .  At the Closing, and on the terms and subject to the conditions set forth in this Agreement, Seller shall sell, assign and deliver to Buyer, and Buyer shall purchase and accept from Seller, the Seller LLC Interest.

     Section 1.02       Purchase Price .  The purchase price to be paid by Buyer to Seller for the Seller LLC Interest and, if transferred to Buyer in accordance with the terms hereof, the Other Yuma Assets (the “ Purchase Price ”) shall equal (a) the Base Purchase Price (which amount shall be adjusted in accordance with Section 1.03 ), plus (b) the Deferred Yuma Compensation Amount (if any).

(a)      Within sixty (60) days after the Closing, Seller shall prepare and deliver to Buyer a written statement, together with supporting work papers with respect to the calculation of the amounts set forth therein (the “ Adjustment Statement ”), which reflects the Working Capital as of the Effective Date.  The items reflected on the Adjustment Statement shall be determined in accordance with GAAP applied on the same basis, and using the same principles, policies and methods as Seller has applied and used in connection with the preparation of the Proforma 12/31 Balance Sheet.  Buyer agrees to cooperate with Seller in connection with the preparation of the Adjustment Statement and related information, and shall provide to Seller and its representatives such books, records, information, and access to such of NBLLC’s or its Affiliates’ employees and properties during normal business hours as may be reasonably requested from time to time by Seller or its representatives.

(b)      Buyer may dispute the Adjustment Statement and the items reflected therein; provided , however , that Buyer shall notify Seller in writing of any disputed amounts, and provide a reasonably detailed description of the basis of such dispute, within sixty (60) days after Buyer’s receipt of the Adjustment Statement.  In the event of such a dispute, Buyer and Seller shall attempt to reconcile their differences and any resolution by them as to any disputed amounts shall be final, binding and conclusive on the Parties.  If Buyer and Seller are unable to reach a resolution of any such differences within thirty (30) days after Seller’s receipt of Buyer’s written notice of dispute, Buyer and Seller shall submit the amounts remaining in dispute for determination and resolution to the Independent Accounting Firm, which shall be instructed to determine and report to the Parties, within thirty (30) days after such submission, a resolution of such remaining disputed amounts, and such resolution shall be final, binding and conclusive on the Parties hereto with respect to the remaining amounts disputed.  The fees and disbursements of the Independent Accounting Firm shall be shared equally by Buyer and Seller.  For the avoidance of doubt, the Adjustment Statement and the amounts reflected thereon shall be deemed to be modified to the extent of any changes thereto that become final, binding and conclusive on the Parties based on mutual agreement or a determination of the Independent Accounting Firm in accordance with this Section 1.03(b) .

(c)      Within five (5) Business Days after the earliest to occur of (i) a mutual written agreement of Buyer and Seller with respect to the Adjustment Statement, (ii) the termination of the 60-day period described in Section 1.03(b) if Buyer does not provide a notice of dispute within such period as provided therein and (iii) the final determination of all such disputed amounts in accordance with Section 1.03(b) , (A) if Working Capital as of the Effective Date exceeds the Estimated Working Capital, Buyer shall pay Seller the amount of such excess, and (B) if Working Capital as of the Effective Date is less than the Estimated Working Capital, Seller shall pay to Buyer the amount of such deficiency.  All payments made pursuant to the previous sentence shall be paid together with interest thereon for the period commencing on the Effective Date through the date of payment, calculated at the Prime Rate in effect on the Effective Date, in cash by wire transfer of immediately available funds.

     Section 1.04       Purchase Price Allocation for Tax Purposes .  Within one hundred eighty (180) days after the Closing Date, Buyer will provide to Seller a copy of Internal Revenue Service Form 8594 and any required exhibits thereto (the “ Asset Acquisition Statement ”) with Buyer’s proposed allocation of the Purchase Price (and all other applicable amounts) among the assets of NBLLC.  If Seller disputes Buyer’s proposed allocation, Seller will give Buyer written notice of such dispute (“ Tax Dispute Notice ”) within thirty (30) days after receipt of the Asset Acquisition Statement setting forth the matters in dispute and the specific grounds of each dispute.  If Buyer does not receive a Tax Dispute Notice from Seller within such thirty (30) day period, Seller will be deemed to have agreed to, and accepted, such Asset Acquisition Statement.  Buyer and Seller will endeavor in good faith to resolve any disputes with respect to the Asset Acquisition Statement within fifteen (15) days after Buyer’s receipt of a Tax Dispute Notice from Seller and if the Parties cannot resolve any such disputes within such fifteen (15) day period, Buyer shall engage a nationally recognized independent accounting, law or appraisal firm chosen jointly by Buyer and Seller for resolution.  Both Buyer and Seller agree to accept such firm’s determination with respect to the Asset Allocation Statement, agree to file Forms 8594 with the Internal Revenue Service in accordance to such allocation and agree not to take any position before any Tax authority inconsistent therewith.  Any fees, costs and expenses for such engagement will be borne equally by Buyer and Seller.

    Section 1.05       Time and Place of the Closing .  Upon the terms and subject to the satisfaction of the conditions contained in this Agreement, the closing of the transactions contemplated by this Agreement (the “ Closing ”) shall take place at the offices of Orrick, Herrington & Sutcliffe LLP, 405 Howard Street, San Francisco, CA 94105 at 10:00 a.m., local time, on the fifth (5 ^th ) Business Day following the date on which all of the conditions to each Party’s obligations hereunder have been satisfied or waived (other than conditions to be satisfied at the Closing), or at such other place or time as the Parties may agree.  The date and time at which the Closing actually occurs is hereinafter referred to as the “ Closing Date .”  Other than with respect to those matters that are effective or applicable as of the Effective Date as expressly provided herein, the Closing shall be effective for all purposes as of 12:01 a.m. Eastern time on the Closing Date.

     Section 1.06       Closing Statement; Closing Payment .

(a)      On the third (3 ^rd ) Business Day prior to the Closing, Seller shall deliver to Buyer a statement (the “ Closing Statement ”) setting forth (i) the Estimated Working Capital and (ii) the Interest Amount.  The Closing Statement shall be prepared by Seller in good faith and be accompanied by reasonably detailed supporting documentation as appropriate.

(b)      At the Closing, Buyer shall pay or cause to be paid to Seller, in cash, an amount equal to the Closing Payment by wire transfer of immediately available funds to the account or accounts designated by Seller prior to the Closing.

     Section 1.07       Deliveries by Seller .  At the Closing, Seller shall deliver or cause to be delivered to Buyer the following:

(a)      a certificate or certificates representing the Seller LLC Interest or other evidence of ownership, duly and validly endorsed in favor of Buyer;

(b)      evidence of the receipt of each Seller Required Approval;

(c)      the Assignment and Assumption Agreement, duly executed by Seller;

(d)      an executed certificate of non-foreign status satisfying the requirements of Treasury Regulation Section 1.445-2(b)(2) (the “ Closing Tax Certificate ”);

(e)      written resignations of the directors and officers (or persons holding similar offices) of NBLLC, such resignations to be effective concurrently with the Closing on the Closing Date; and

(f)      such other agreements, documents, instruments and writings as are expressly required to be delivered by Seller at or prior to the Closing Date pursuant to this Agreement.

Section 1.08       Deliveries by Buyer .  At the Closing, Buyer shall deliver or cause to be delivered to Seller the following:

(a)      the Closing Payment by wire transfer of immediately available funds;

(b)      evidence of the receipt of each Buyer Required Regulatory Approval;

(c)      the Assignment and Assumption Agreement, duly executed by Buyer; and

(d)      such other agreements, documents, instruments and writings as are expressly required to be delivered by Buyer at or prior to the Closing Date pursuant to this Agreement.

     Except as set forth in the Schedules, Seller hereby represents and warrants to Buyer as follows (it being understood and agreed that (x) the representations and warranties set forth in this Article II shall in no way apply to the Yuma Assets or the Excluded Assets and (y) the only representations and warranties to be made by Seller or any of its Affiliates with respect to the Yuma Assets shall be set forth in the Yuma Transfer Agreement when and if delivered in accordance with the terms hereof):

     Section 2.01       Organization and Qualification of Seller .  Seller is a corporation duly organized, validly existing and in good standing under the laws of the State of California.  Seller has all requisite corporate power and authority to own and operate its business as presently conducted.  Seller is duly qualified as a foreign corporation and is in good standing in each jurisdiction where the character of its properties owned or held under lease or the nature of its activities makes such qualification necessary, except for such failures to be so qualified as would not reasonably be expected to have a Material Adverse Effect.

     Section 2.02       Authorization; Validity and Effect of Transaction Agreements .  Seller has the requisite power and authority to execute, deliver and perform its obligations under this Agreement and the other Transaction Agreements and to consummate the transactions contemplated hereby and thereby.  The execution and delivery of this Agreement and the other Transaction Agreements by Seller and the performance by it of its obligations hereunder and thereunder and the consummation of all of the transactions contemplated hereby and thereby have been (or, with respect to those Transaction Agreements to be delivered at the Closing, will at or prior to the Closing, be) duly authorized by Seller’s board of directors (and, if required, shareholders) and by all other necessary corporate action on the part of it, and no other proceedings are (or will be) necessary for Seller to authorize this Agreement or the other Transaction Agreements and the transactions contemplated hereby or thereby.  This Agreement and the other Transaction Agreements have been (or, with respect to those Transaction Agreements to be delivered at the Closing, will at or prior to the Closing, be) duly and validly executed and delivered by Seller and constitute (or will constitute) legal, valid and binding obligations of Seller, enforceable against Seller in accordance with their terms, except that such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally and general equitable principles (whether considered in a proceeding in equity or at law).

(a)      Other than obtaining the Seller Required Approvals, neither the execution and delivery by Seller of this Agreement or the other Transaction Agreements, nor the performance by Seller of its obligations hereunder or thereunder, nor the consummation of the transactions contemplated hereby or thereby, will: (i) conflict with, or result in the breach of, any provision of its articles of incorporation, bylaws or any other governing or organizational document of Seller; (ii) violate any statute, law, ordinance, rule or regulation, applicable to Seller or any of its properties or assets; or (iii) except as set forth on Schedule 2.03(a) , conflict with or result in any violation or breach of or default (with or without notice or lapse of time, or both) under, or give rise to a right of termination, cancellation, suspension, modification or acceleration of any obligation or any increase in any payment required by, or the impairment, loss or forfeiture of any Material benefits, rights or privileges under, or the creation of a Lien on any assets pursuant to (any such conflict, violation, breach, default, right of termination, cancellation or acceleration, loss or Lien, a “ Violation ”) any Contract (x) to which Seller is a party, (y) by which Seller or any of its assets or properties is bound or affected, or (z) pursuant to which such Seller is entitled to any rights or benefits, except for such Violations which would not reasonably be expected to have a Material Adverse Effect.

(b)      Except as set forth on Schedule 2.03(b) and other than obtaining the Seller Required Approvals and the Buyer Required Regulatory Approvals, no consent, approval, authorization, exemption or waiver of, permit from, or declaration, filing or registration with, any Governmental Authority or any other Person is required to be made or obtained by Seller in connection with the execution, delivery and performance of this Agreement or the other Transaction Agreements or the consummation of the transactions contemplated hereby or thereby, except where the failure to obtain such consent, approval, authorization, permit or declaration or to make such filing or registration would not reasonably be expected to have a Material Adverse Effect.

     Section 2.04       Ownership and Delivery of the Seller LLC Interest .  Seller is the sole legal and beneficial owner of the Seller LLC Interest.  The Seller LLC Interest constitutes the entire ownership interest in and to NBLLC.  Except as set forth on Schedule 2.04 , Seller will, at the Closing, transfer good and valid title to the Seller LLC Interest to Buyer, free and clear of any and all Liens.  There are no outstanding subscriptions, options, warrants, calls, rights, commitments, arrangements, understandings or agreements of any character affecting Seller’s right to transfer the Seller LLC Interest as contemplated herein. 

     Section 2.05       No Brokers .  Seller does not have any liability to pay any compensation to any broker, finder or agent with respect to the transactions contemplated hereby based upon arrangements made by or on behalf of Seller.

     Section 2.06       Legal Proceedings Relating to Seller .  There are no actions or proceedings pending or, to the Knowledge of Seller, threatened, against Seller before any court, arbitrator or Governmental Authority acting in an adjudicative capacity, which, if adversely determined, would prohibit or restrain the execution, delivery or performance of this Agreement or the other Transaction Agreements or any of the transactions contemplated hereby or thereby.  Seller is not subject to any outstanding judgments, rules, orders, writs, injunctions or decrees of any court or Governmental Authority which would prohibit or restrain the execution, delivery or performance of this Agreement, the other Transaction Agreements or any of the transactions contemplated hereby or thereby, and to the Knowledge of Seller, none are threatened.

     Section 2.07       Absence of Certain Changes .  Except as set forth on Schedule 2.07 , between December 31, 2008 and the date hereof, (a) NBLLC has incurred no liabilities or obligations, fixed, contingent, accrued or otherwise that are of the type that are required to be set forth on a balance sheet prepared in accordance with GAAP (except for liabilities and obligations incurred in the ordinary course of business); (b) NBLLC has conducted the Business, in all Material respects, in the ordinary course; and (c) no event, occurrence or other matter has occurred that would reasonably be expected to have a Material Adverse Effect.

     Section 2.08       Organization and Qualification of NBLLC .  NBLLC is a limited liability company duly organized, validly existing and in good standing under the laws of the State of Delaware.  NBLLC has all requisite limited liability company power and authority to own and operate its business as presently conducted.  NBLLC is duly qualified as a foreign limited liability company in each of the jurisdictions where the character of its properties owned or held under lease or the nature of its activities makes such qualification necessary, except for such failures to be so qualified as would not reasonably be expected to have a Material Adverse Effect.

     Section 2.09       No Subsidiaries .   

(a)      NBLLC does not own any equity interests in any other Person.

(b)      NBLLC is not a party to any Contract, or otherwise subject to any legal restriction, restricting its ability to pay dividends out of profits or make any other similar distributions of profits, except (i) as set forth on Schedule 2.09(b) and (ii) for legal restrictions, if any, under the Delaware Limited Liability Company Act.

      Section 2.10        Financial Statements .  Copies of the unaudited financial statements (including any notes and schedules thereto) of NBLLC as at December 31, 2008 are attached as Schedule 2.10 (the “ Financial Statements ”).  The Financial Statements (including in each case any related schedules and notes) fairly present in all Material respects the financial position of NBLLC as of the date specified therein, and the results of its operations for the respective period so specified, and have been prepared in accordance with GAAP consistently applied throughout the period involved.

(a)      Except as set forth on Schedule 2.11(a) , there are no actions, suits or proceedings pending or, to the Knowledge of Seller, threatened against NBLLC, in any court or before any arbitrator of any kind or before or by any Governmental Authority that would reasonably be expected to have a Material Adverse Effect.  No litigation is currently pending against NBLLC by Rockford Corporation in connection with construction work  on the Pipeline, and NBLLC has never been a party to any such proceeding.

(b)      NBLLC is not in default under any order, judgment, decree or ruling of any court, arbitrator or Governmental Authority which default would reasonably be expected to have a Material Adverse Effect.

     Section 2.12       Tax Matters .  Except as set forth on Schedule 2.12 :

(a)      all Material Tax Returns required to be filed by or with respect to the NBLLC have been or will be timely filed with the appropriate taxing authorities in all jurisdictions in which such Tax Returns are required to be filed;

(b)      such Tax Returns are or will be true and correct in all Material respects, and all Taxes reported on such Tax Returns have been or will be timely paid;

(c)      all Material Taxes and Tax liabilities due by or with respect to the income, assets or operations of NBLLC for all taxable years or portions thereof that end on or before the Closing Date have been timely paid or will be timely paid;

(d)      NBLLC has not, and Seller has not with respect to NBLLC or its assets, extended or waived the application of any statute of limitations of any jurisdiction regarding the assessment or collection of any Tax;

(e)      there are no audits, claims, assessments, levies, administrative proceedings, or lawsuits pending, or to the Knowledge of Seller, threatened against NBLLC by any taxing authority, and NBLLC has not received any written notices from any taxing authority relating to any issue which could have a Material affect on the Tax liability of NBLLC after the Closing Date;

(f)      since the Acquisition Date, no election has been made by NBLLC to be classified as an association taxable as a corporation for U.S. federal, state or local income tax purposes and NBLLC is currently and at all times since the Acquisition Date has been treated as a disregarded entity for all such purposes;

(g)      there are no Liens for Taxes (other than for current Taxes not yet due or payable) upon the assets of NBLLC;

(h)      none of the assets of NBLLC, directly or indirectly, secures any debt the interest on which is tax exempt under Section 103(a) of the Code;

(i)      Seller is not a Person other than a United States person within the meaning of the Code, and the transactions contemplated herein are not subject to the tax withholding provisions of the Code;

(j)      all Taxes which NBLLC is (or was) required by law to withhold or collect in connection with amounts paid or owing to any employee, independent contractor, creditor, stockholder or other third party have been duly withheld or collected, and have been or will be timely paid over to the proper authorities to the extent due and payable;

(k)      there are no tax sharing, allocation, indemnification or similar agreements in effect as between NBLLC or any Affiliate and any other party (including Seller and any predecessors or Affiliates thereof) under which Buyer or NBLLC could be liable for any Taxes of any party after the Closing Date;

(l)      NBLLC has not applied for, nor has it been granted, or agreed to any accounting method change for which it will be required to take into account any adjustment under Section 481 of the Code or any similar provision of the Code or the corresponding tax laws of any nation, state or locality; and

(m)      since the Acquisition Date, no written claim has ever been made by any taxing Governmental Authority in a jurisdiction where NBLLC does not file Tax Returns that NBLLC is or may be subject to taxation by that jurisdiction.

     Section 2.13       Title to Real and Personal Property .  Except as set forth on Schedule 2.13 , NBLLC has good title in fee simple to, or has valid rights to lease or use, by easement, license, Contract or otherwise, all items of real and personal property used in the ordinary course of the Business, in each case free and clear of all Liens, except those that (a) do not materially interfere with the current use of such property by NBLLC or (b) constitute Permitted Encumbrances.

     Section 2.14       Permits; Intellectual Property .  

(a)      NBLLC owns or possesses all Permits, patents, copyrights, service marks, trademarks and trade names, or rights thereto, necessary for the operation, ownership and maintenance of the Pipeline and the conduct of the Business, except where the failure to own or possess the same would not reasonably be expected to have a Material Adverse Effect.  Since the Acquisition Date, NBLLC has not received any written notice of any revocation or modification of any such Permit, patent, copyright, service mark, trademark or trade name and has not received any written notice that such Permit, patent, copyright, service mark, trademark or trade name will not be renewed in the ordinary course of business.

(b)      Since the Acquisition Date, NBLLC has made all declarations and filings with the appropriate Governmental Authorities that are necessary for the ownership, maintenance or lease of its Material properties and the conduct of the Business, except where the failure to make the same would not reasonably be expected to have a Material Adverse Effect.

     Section 2.16       Employee Matters .  

(a)      NBLLC does not currently have and has never had any employees.  Except as set forth on Schedule 2.16(a) , there are no employee or employee-benefit related liabilities to which NBLLC is subject.

(b)      The execution and delivery of this Agreement and the consummation of the transactions contemplated hereby do not involve any transaction that, absent an applicable exemption, is subject to the prohibitions of Section 406(b) of ERISA or in connection with which, absent an applicable exemption, a Tax could be imposed pursuant to Section 4975(c)(1)(A)-(D) of the Code.

     Section 2.17       No Violation or Default .  Except as set forth on Schedule 2.17 , NBLLC is not (a) in violation of the NBLLC Agreement, its certificate of formation or any other governing or organizational document of NBLLC; (b) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance by NBLLC of any term, covenant or condition contained in any Contract to which NBLLC is a party or by which NBLLC is bound or to which any of the property or assets of NBLLC is subject; or (c) in violation of any law or statute or any judgment, or order, rule or regulation of any court or arbitrator or Governmental Authority, except, in the case of clauses (b) and (c) above, for any such default or violation that would not reasonably be expected to have a Material Adverse Effect.  Notwithstanding the foregoing, it is understood and agreed that the representations and warranties set forth in this Section 2.17 shall not apply to (i) matters relating to Taxes (as the sole and exclusive representations and warranties regarding Taxes are set forth in Section 2.12 ), (ii) Permits, declarations and filings (as the sole and exclusive representations and warranties regarding Permits, declarations and filings are set forth in Section 2.14 ), (iii) employee matters (as the sole and exclusive representations and warranties regarding employee matters are set forth in Section 2.16 ) and (iv) environmental matters (as the sole and exclusive representations and warranties regarding environmental matters are set forth in Section 2.20 ).

Section 2.18       Material NBLLC Agreements .  The Contracts set forth on Schedule 2.18 (collectively, the “ Material NBLLC Agreements ”) constitute all Material gas transportation contracts, operation and maintenance agreements, construction contracts and other Material contracts to which NBLLC is a party or by which it is bound or to which any of the property or assets of NBLLC is subject.  The Material NBLLC Agreements have been duly authorized, executed and delivered by NBLLC and constitute valid and legally binding agreements of NBLLC enforceable against NBLLC in accordance with their terms, except that such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally and general equitable principles (whether considered in a proceeding in equity or at law).

     Section 2.19       Insurance .  NBLLC has insurance with Reputable Insurers covering its properties (including the Pipeline and related equipment) against loss or damage of the kinds customarily insured against by companies similarly situated in the industry in which NBLLC conducts the Business, in such amounts and with such deductibles as is customary for similarly situated companies; and, since the Acquisition Date, NBLLC has not received written notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance.

     Section 2.20       Compliance With Environmental Laws .  Except as set forth on Schedule 2.20 , since the Acquisition Date (a) NBLLC has been operated in compliance with any and all Environmental Laws; (b) NBLLC has received and is in compliance with all Permits required of it under applicable Environmental Laws to conduct the Business; (c) NBLLC has not been the subject of any outstanding order or judgment from a Governmental Authority under applicable Environmental Laws requiring remediation or payment of a fine in an amount in excess of $500,000 individually or in the aggregate, and (d) NBLLC has not received any written notice of any actual or potential liability for the violation of, or noncompliance with any Environmental Law, or the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants under any Environmental Law, except in the case of the foregoing clauses (a) and (b) for any such noncompliance as would not reasonably be expected to have a Material Adverse Effect.  Except for actions and conditions which have not had and would not reasonably be expected to have a Material Adverse Effect, to the Knowledge of Seller no condition exists on any property currently owned or leased by NBLLC which would subject NBLLC or such property to any remedial obligations or liabilities.

     Section 2.21       No Conflict; Required Filings and Consents Applicable to NBLLC .   

(a)      Except as set forth on Schedule 2.21(a) , neither the execution and delivery by Seller of this Agreement or the other Transaction Agreements, nor the performance by Seller of the obligations hereunder or thereunder, nor the consummation of the transactions contemplated hereby or thereby, will result in a Violation of any Contract (i) to which NBLLC is a party, (ii) by which NBLLC or any of its assets or properties is bound or affected, or (iii) pursuant to which NBLLC is entitled to any rights or benefits, except for such Violations which would not reasonably be expected to have a Material Adverse Effect.

(b)      Except as set forth on Schedule 2.21(b) , no consent, approval, authorization, exemption or waiver of, permit from, or declaration, filing or registration with, any Governmental Authority, or any other Person is required to be made or obtained by NBLLC in connection with the execution, delivery and performance of this Agreement or the other Transaction Agreements or the consummation of the transactions contemplated thereby, except where the failure to obtain such consent, approval, authorization, permit or declaration or to make such filing or registration would not reasonably be expected to have a Material Adverse Effect.

     Section 2.22       Intercompany Matters .  Except for the Transaction Documents, the documents contemplated by Section 4.05 or as set forth in Schedule 2.22 , there are no intercompany contracts or other arrangements, including arrangements regarding payment of Taxes, between NBLLC on the one hand and Seller and its Affiliates on the other that (a) can not be terminated by NBLLC upon notice of 30 days or less and (b) would subject NBLLC to any obligations or liabilities, or otherwise bind NBLLC, subsequent to the Closing.

     Buyer hereby represents and warrants to Seller as follows:

     Section 3.01       Organization and Qualification of Buyer .  Buyer is a limited partnership duly organized, validly existing and in good standing under the laws of Delaware.  Buyer has all requisite power and authority to own and operate its business as presently conducted.  Buyer is duly qualified as a foreign limited partnership and is in good standing in each jurisdiction where the character of its properties owned or held under lease or the nature of its activities makes such qualification necessary, except for such failures to be so qualified as would not reasonably be expected to have a material adverse effect on Buyer.

     Section 3.02       Authorization; Validity and Effect of Transaction Agreements .  Buyer has the requisite power and authority to execute, deliver and perform its obligations under this Agreement and the other Transaction Agreements and to consummate the transactions contemplated hereby and thereby.  The execution and delivery of this Agreement and the other Transaction Agreements by Buyer and the performance by it of its obligations hereunder and thereunder and the consummation of all of the transactions contemplated hereby and thereby have been (or, with respect to those Transaction Agreements to be delivered at the Closing, will at or prior to the Closing, be) duly authorized by Buyer’s general partner and by all other necessary limited partnership action on the part of it, and no other proceedings are (or will be) necessary for Buyer to authorize this Agreement or the other Transaction Agreements and the transactions contemplated hereby or thereby.  This Agreement and the other Transaction Agreements have been (or, with respect to those Transaction Agreements to be delivered at the Closing, will, at or prior to the Closing, be) duly and validly executed and delivered by Buyer and constitute (or will constitute) legal, valid and binding obligations of Buyer, enforceable against Buyer in accordance with their terms, except that such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium and other similar laws relating to or affecting creditors’ rights generally and general equitable principles (whether considered in a proceeding in equity or at law).

     Section 3.03       No Conflict; Required Filings and Consents Applicable to Buyer .  

(a)      Other than obtaining the Buyer Required Regulatory Approvals, neither the execution and delivery by Buyer of this Agreement or the other Transaction Agreements, nor the performance by Buyer of its obligations hereunder or thereunder, nor the consummation of the transactions contemplated hereby or thereby, will:  (i) conflict with, or result in the breach of, any provision of its certificate of limited partnership or limited partnership agreement or any other governing or organizational document of Buyer; (ii) violate any statute, law, ordinance, rule or regulation applicable to Buyer or any of its respective properties or assets; or (iii) conflict with or result in any Violation of any Contract (x) to which Buyer is a party, (y) by which Buyer or any of its assets or properties is bound or affected, or (z) pursuant to which Buyer is entitled to any rights or benefits, except for such Violations which would not reasonably be expected to have a material adverse effect on Buyer

(b)      Other than obtaining the Buyer Required Regulatory Approvals and the Seller Required Approvals, no consent, approval, authorization, exemption or waiver of, permit from, or declaration, filing or registration with, any Governmental Authority, or any other Person is required to be made or obtained by Buyer in connection with the execution, delivery and performance of this Agreement or the other Transaction Agreements or the consummation of the transactions contemplated hereby or thereby, except where the failure to obtain such consent, approval, authorization, permit or declaration or to make such filing or registration would not reasonably be expected to have a material adverse effect on Buyer.

Section 3.04       No Brokers .  Buyer has no liability to pay any compensation to any broker, finder or agent with respect to the transactions contemplated hereby based upon arrangements made by or on behalf of Buyer.

Section 3.05       Legal Proceedings Relating to Buyer .  There are no actions or proceedings pending or, to Buyer’s knowledge, threatened against Buyer before any court or Governmental Authority acting in an adjudicative capacity, which, if adversely determined, would prohibit or restrain the execution, delivery or performance of this Agreement or the other Transaction Agreements or any of the transactions contemplated hereby or thereby.  Buyer is not subject to any outstanding judgments, rules, orders, writs, injunctions or decrees of any court or Governmental Authority which would prohibit or restrain the execution, delivery or performance of this Agreement, the other Transaction Agreements or any of the transactions contemplated hereby or thereby.

Section 3.06       Acquisition for Investment .  Buyer has such knowledge and experience in financial and business matters that Buyer is capable of evaluating the merits and risks of the investment contemplated by this Agreement and making an informed investment decision with respect thereto.  Buyer is acquiring the Seller LLC Interest for Buyer’s own account, for investment only and not with a view to, or any present intention of, effecting a distribution of such Seller LLC Interest in violation of the Securities Act.  Buyer acknowledges that the Seller LLC Interest has not been registered under the Securities Act or the securities laws of any state or other jurisdiction and cannot be disposed of except in accordance with the Securities Act and any applicable state laws.  Buyer is an accredited investor (within the meaning of Regulation D promulgated under the Securities Act).

Section 3.07       No Other Representations; Waiver of Implied Warranties .  Except as otherwise provided in this Agreement, Seller has not made and does not make any other representations or warranties as to the Seller LLC Interest, NBLLC, the Business or any matter or thing affecting or relating to NBLLC and its business, operations, assets, properties, liabilities, financial condition, results of operation or affairs.  Buyer hereby waives, to the extent permitted by law, any implied warranty applicable to the transactions contemplated hereby (including any implied warranty of merchantability or fitness for a particular purpose).  Buyer acknowledges that it has had the opportunity to conduct its own independent investigation, analysis and evaluation of the Seller LLC Interest, NBLLC and the Business.

     Section 4.01       Expenses . Buyer and Seller shall be solely responsible for their respective expenses and costs incurred in connection with the execution and performance of this Agreement, the other Transaction Agreements and the transactions contemplated hereby and thereby.

     Section 4.02       Cash .  For the avoidance of doubt and in accordance with the terms set forth herein, (a) any cash received by NBLLC on or prior to the Effective Date will be for the account of Seller and (b) any cash received by NBLLC after the Effective Date will be for the account of Buyer (it being understood and agreed that, in accordance with the foregoing, if and to the extent that cash is received by NBLLC after the Effective Date at a time when the Closing has not yet occurred, Seller shall not be permitted to cause NBLLC to distribute such cash to Seller but rather shall cause such cash to remain in NBLLC until the Closing).

     Section 4.03       Access to Information by Buyer .  Seller shall grant Buyer reasonable access during normal business hours to all books and records concerning NBLLC and the Seller LLC Interest which Seller has in its possession or control as Buyer deems reasonably necessary or advisable in connection with the consummation of the transactions contemplated hereby; provided that such access shall not materially interfere with normal operations of NBLLC.

     Section 4.04       Conduct of the Business Pending the Closing Date .  

(a)      Except as required or permitted by this Agreement, or otherwise approved in writing by Buyer (which approval shall not be unreasonably withheld or delayed) during the period commencing on the date hereof and ending on the Closing Date, Seller will, and will cause NBLLC to (it being understood and agreed that the following provisions shall not apply to actions taken or not taken by Seller or NBLLC with respect to the Yuma Assets):

                       (i)      operate and maintain the Business in all material respects in the usual, regular and ordinary manner consistent with past practices, and to the extent consistent with such operation and maintenance, preserve the present business organization of the Business;

                       (ii)      maintain its books, accounts and records relating to the Business in the usual, regular and ordinary manner, on a basis consistent with past practice, comply in all Material respects with all laws, rules or regulations of any Governmental Authority and contractual obligations applicable to the Business or to the conduct of the Business and perform all of its Material obligations relating to the Business;

                       (iii)      not waive any Material claims or rights relating to the Business;

                       (iv)      after obtaining Knowledge thereof, give notice to Buyer of any claim or litigation (threatened or instituted) or any other event or occurrence which would reasonably be expected to have a Material Adverse Effect, or which could reasonably be expected to cause Seller to breach any representation, warranty or covenant contained in this Agreement;

                       (v)      not file an election to have NBLLC classified as an association taxable as a corporation for U.S. federal, state or local income tax purposes; and

                       (vi)      not agree, whether in writing or otherwise, to take any action which is inconsistent with this Section 4.04(a) .

(b)      Notwithstanding anything to the contrary in this Section 4.04 , prior to the Closing Date, Buyer, on the one hand, and Seller, on the other hand, will act independently of each other in making decisions as to their respective businesses.

     Section 4.05       Recapitalization; Other Pre-Closing Transactions .  Seller shall, and shall cause NBLLC to, effect the Recapitalization of NBLLC prior to Closing.  Prior to the Closing, each of Buyer and Seller shall, and, as applicable, shall cause their respective Affiliates to, execute and deliver the following documents and, if applicable, carry out and effect the transactions contemplated thereby: (a) a common unit purchase agreement in the form of Exhibit A , (b) an exchange agreement in the form of Exhibit B and (c) an amendment to the Amended and Restated Agreement of Limited Partnership of Limited Partnership in the form of Exhibit C .

     Section 4.06       Disputes .  In the event of a Dispute, upon the written request (a “ Request ”) of any Party to this Agreement, the matter shall immediately be referred to senior officers of each Party designated by such Party for resolution.  The designated senior officers shall meet immediately and attempt in good faith to negotiate a resolution of the Dispute.  If the Parties are unable to resolve the Dispute within 15 Business Days after receipt by a Party of a Request, then either Party may seek any legal avenue available to resolve the Dispute.

     Section 4.07       Excluded Assets .  Prior to the Closing, Seller shall cause NBLLC to transfer the Excluded Assets from NBLLC to Seller or an Affiliate of Seller.

     Section 4.08       Commercially Reasonable Efforts .  Each Party shall use its commercially reasonable efforts to take, or cause to be taken, all actions, and to do, or cause to be done, all things reasonably necessary, proper or advisable to consummate and make effective the transactions contemplated by this Agreement and the other Transaction Agreements as soon as reasonably practicable, including such actions or things as any Party hereto may reasonably request in order to cause any of the conditions to any other Party’s obligation to consummate such transactions specified in Article V to be fully satisfied, and as promptly as is reasonably practicable cooperate with and furnish information to each other in connection with any requirements imposed upon any of them with respect thereto.  In furtherance of the foregoing covenant, each of Buyer and Seller shall prepare and submit, as soon as practicable following the execution by Seller and Buyer of this Agreement, all necessary filings in connection with the transactions contemplated by this Agreement that may be required under the HSR Act and the rules and regulations promulgated thereunder.  Each Party shall, if applicable, request expedited treatment of such filings, shall promptly make any appropriate or necessary subsequent or supplementary filings, and shall cooperate with each other in the preparation of such filings as is reasonably necessary and appropriate.  The cost of any filings under the HSR Act required in connection with the transactions contemplated hereby shall be borne equally by Buyer and Seller.

     Section 4.09       Schedules .

(a)      Any information disclosed by any Party hereto pursuant to any Schedule hereto shall be deemed to be disclosed to the other Party for all purposes of this Agreement, the Transaction Agreements and the Yuma Transfer Agreement (if any).  Neither the specification of any dollar amount or any item or matter in any provision of this Agreement, any Transaction Agreement or the Yuma Transfer Agreement (if any) nor the inclusion of any specific item or matter in any Schedule hereto or thereto is intended to imply that such amount, or higher or lower amounts, or the item or matter so specified or included, or other items or matters, are or are not Material, and no party shall use the fact of the specification of any such amount or the specification or inclusion of any such item or matter in any dispute or controversy between the parties as to whether any item or matter is or is not Material for purposes of this Agreement, any Transaction Agreement or the Yuma Transfer Agreement (if any).  Neither the specification of any item or matter in any provision of the Agreement, any Transaction Agreement or the Yuma Transfer Agreement (if any) nor the inclusion of any specific item or matter in any Schedule hereto or thereto is intended to imply that such item or matter, or other items or matters, are or are not in the ordinary course of business, and no party shall use the fact of the specification or the inclusion of any such item or matter in any dispute or controversy between the parties as to whether any item or matter is or is not in the ordinary course of business for purpose