CONTRIBUTION AGREEMENT

BY AND AMONG

EL PASO CORPORATION

EL PASO NORIC INVESTMENTS III, L.L.C.

COLORADO INTERSTATE GAS COMPANY

EPPP CIG GP HOLDINGS, L.L.C.

EL PASO PIPELINE PARTNERS, L.P.

AND

EL PASO PIPELINE PARTNERS OPERATING COMPANY, L.L.C.

July 24, 2009

TABLE OF CONTENTS

Disclosure Schedules

Exhibit A                       Form of Contribution, Conveyance and Assumption Agreement

Exhibit B                       Form of Demand Note

Exhibit C                       Form of Cancellation Agreement

This Contribution Agreement (the “ Agreement ”) is made and entered into as of July 24, 2009, by and among El Paso Corporation, a Delaware corporation (“ El Paso ”), El Paso Noric Investments III, L.L.C., a Delaware limited liability company and indirect wholly-owned subsidiary of El Paso (“ EP Noric ”), Colorado Interstate Gas Company, a Delaware general partnership, (“ CIG ”), El Paso Pipeline Partners, L.P., a Delaware limited partnership (the “ Partnership ”), El Paso Pipeline Partners Operating Company, L.L.C., a Delaware limited liability company and direct wholly-owned subsidiary of the Partnership (the “Operating Company” ) and EPPP CIG GP Holdings, L.L.C., a Delaware limited liability company and an indirect wholly-owned subsidiary of the Partnership (“ EPPP CIG ”).  El Paso and EP Noric are referred to herein collectively as the “ Contributing Parties ,” the Partnership, the Operating Company and EPPP CIG are referred to herein collectively as the “ Partnership Parties ” and the Contributing Parties, Partnership Parties and CIG are referred to herein collectively as the “ Parties .”

WHEREAS, EP Noric owns a 60% general partner interest in CIG and EPPP CIG owns a 40% general partner interest in CIG; and

WHEREAS, pursuant to the Contribution Agreement (defined below), the Contributing Parties desire to contribute, transfer and convey to the Partnership a 18% general partner interest in CIG (the “ Subject Interest ”) in exchange for total cash consideration of $214.5 million (the “ Consideration ”); and

WHEREAS, after giving effect to the completion of the contribution of the Subject Interest referred to above pursuant to the terms of this Agreement and the Contribution Agreement, EP Noric and EPPP CIG will own a 42% and 58% general partner interest in CIG, respectively;

NOW, THEREFORE, in consideration of the premises and the respective representations, warranties, covenants, agreements and conditions contained herein, the Parties agree as follows:

The terms defined in this Section  1.1  shall, when used in this Agreement, have the respective meanings specified herein, with each such definition equally applicable to both singular and plural forms of the terms so defined:

“ Additional Distribution Amount ” means 18% of any cash distributions made by CIG with respect to its operations after the Effective Time and prior to Closing.  For avoidance of doubt, the distributions made by CIG on April 30, 2009 with respect to its operations for the first quarter of 2009 are not to be given effect in the calculation of any Additional Distribution Amount. In addition, in the event that Closing occurs on July 30, 2009 and on such day (but after the Closing), EPPP CIG receives 58% of the cash distributions made by CIG on July 30, 2009 with respect to CIG’s operations for the second quarter 2009, such cash distributions for the second quarter are not to be given effect in the calculation of any Additional Distribution Amount.

“ Affiliate ,” when used with respect to a Person, means any other Person that directly or indirectly Controls, is Controlled by or is under common Control with such first Person.

“ Agreement ” has the meaning assigned to such term in the preamble.

“ Ancillary Documents ” means the Contributing Parties Ancillary Documents and the Partnership Ancillary Documents.

“ Applicable Law ” has the meaning assigned to such term in Section  3.3 .

“ Associated Employees” has the meaning assigned to such term in Section 3.13 .

“ Business Day ” means any day other than a Saturday, Sunday or legal holiday on which banks in Houston, Texas are authorized or obligated by law to close.

“ Cancellation Agreement ” means the cancellation agreement in substantially the form attached as Exhibit C hereto.

“ Cash Pooling Arrangements ” means the cash pooling arrangement among El Paso and its Affiliates, pursuant to which El Paso and its Affiliates receive substantially all cash due to (and make substantially all payments for) certain of its Affiliates, including CIG, which amounts are reflected as intercompany receivables or payables or as capital contributions and distributions in accordance with GAAP.

“ Cash Pooling Transactions ” has the meaning assigned to such term in Section  5.6 .

“ Ceiling Amount ” has the meaning assigned to such term in Section  9.10 .

“ CERCLA ” means the Comprehensive Environmental Response, Compensation, and Liability Act.

“ CIG ” has the meaning assigned to such term in the preamble.

“ CIG 10-K ” has the meaning assigned to such term in Section 3.5 .

“CIG Entities” means (i) CIG, (ii) any subsidiary of CIG and (iii) any Person in which CIG or any subsidiary of CIG owns an equity interest constituting 50% or more of the outstanding voting interests of such Person.

“ Closing ” has the meaning assigned to such term in Section  2.1 .

“ Closing Date ” has the meaning assigned to such term in Section  2.3 .

“ Code ” means the Internal Revenue Code of 1986, as amended, and the rules and regulations issued thereunder.

“ Conflicts Committee ” has the meaning assigned to such term in the Partnership Agreement.

“ Consideration ” has the meaning assigned to such term in the Recitals.

“ Contributing Indemnified Parties ” has the meaning assigned to such term in Section  9.2 .

“ Contributing Parties ” has the meaning assigned to such term in the preamble.

“ Contributing Parties Aggregated Group ”   has the meaning assigned to such term in Section 3.13(e) .

“ Contributing Parties Ancillary Documents ” means each agreement, document or certificate to be delivered by the Contributing Parties or CIG at Closing pursuant to Section  2.3(b) , including the Contribution Agreement.

“ Contributing Parties Closing Certificate ” has the meaning assigned to such term in Section  6.1 .

“ Contribution Agreement ” has the meaning assigned to such term in Section  2.1 .

“ Control ,” and its derivatives, mean the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of a Person.

“ Damages ” means liabilities and obligations, including all losses, deficiencies, costs, expenses, fines, interest, expenditures, claims, suits, proceedings, judgments, damages, and reasonable attorneys’ fees and reasonable expenses of investigating, defending and prosecuting litigation.

“ Debt Amount ” means, with respect to the relevant Person, determined in accordance with GAAP, the sum of such Person’s liabilities for indebtedness for borrowed money, capital leases and other transactions reflected on a balance sheet prepared in accordance with GAAP as financing transactions, in each case whether classified as a current or a non-current liability, excluding debt reflected on the CIG balance sheet related to the WYCO High Plains Pipeline and Totem Storage projects.

“ Deductible Amount ” has the meaning assigned to such term in Section  9.10 .

“ Demand Note ” means the demand note in substantially the form attached as Exhibit B hereto.

“ Disclosure Schedules ” means the disclosure schedules to this Agreement.

“ Effective Time ” means 12:01 a.m., Houston, Texas time, on April 1, 2009.

“ El Paso ” has the meaning assigned to such term in the preamble.

“ Environmental Laws ” means any federal, state or local statutes, laws, ordinances, rules, regulations, orders, codes, decisions, injunctions or decrees that regulate or otherwise pertain to the protection of the environment, including the management, control, discharge, emission, treatment, containment, handling, removal, use, generation, permitting, migration, storage, release, transportation, disposal, remediation, manufacture, processing or distribution of Hazardous Materials that are or may present a threat to the environment, including the following laws, as amended as of the Effective Time and interpreted by the highest court of competent jurisdiction through the Effective Time:  (i) the Resource Conservation and Recovery Act; (ii) the Clean Air Act; (iii) CERCLA; (iv) the Federal Water Pollution Control Act; (v) the Safe Drinking Water Act; (vi) the Toxic Substances Control Act; (vii) the Emergency Planning and Community Right-to Know Act; (viii) the National Environmental Policy Act; (ix) the Pollution Prevention Act of 1990; (x) the Oil Pollution Act of 1990; (xi) the Hazardous Materials Transportation Act and (xii) all rules, regulations, orders, judgments, decrees promulgated or issued with respect to the foregoing Environmental Laws by Governmental Authorities with jurisdiction in the premises.  The term “Environmental Laws” does not include operating practices or standards that may be employed or adopted by other industry participants or recommended by a Governmental Authority that are not required by such federal, state or local statutes, laws, ordinances, rules, regulations, orders, codes, decisions, injunctions or decrees.

“ Environmental Permits ”   has the meaning assigned to such term in Section 3.10 .

“ EP Noric ” has the meaning assigned to such term in the preamble.

“ EPPP CIG ” has the meaning assigned to such term in the preamble.

“ ERISA ” has the meaning ascribed to such term in Section  3.13(b) .

“ Exchange Act ” means the Securities Exchange Act of 1934, as amended.

“ Existing CIG Partnership Agreement ” means the General Partnership Agreement, dated November 1, 2007, as amended by Amendment No. 1, dated September 30, 2008, of CIG.

“ FERC ” means the Federal Energy Regulatory Commission.

“ Financial Statements ” has the meaning assigned to such term in Section  3.5 .

“ GAAP ” means generally accepted accounting principles in the United States of America.

“ General Partner ” means the general partner of the Partnership, which as of the Effective Time and the date of this Agreement is El Paso Pipeline GP Company, L.L.C.

“ Governmental Authority ” means any federal, state, municipal or other governmental court, department, commission, board, bureau, agency or instrumentality.

“ Growth Capital Requirements ” means cash expenditures for expansion and other capital improvements other than maintenance expenditures and  expenditures for facility repairs associated with hurricane damage and maintenance recorded in the financial statements of CIG as capital expenditures in accordance with GAAP.

“ Hazardous Materials ” means any substance, whether solid, liquid, or gaseous:  (i) which is listed, defined, or regulated as a “hazardous material,” “hazardous waste,” “solid waste,” “hazardous substance,” “toxic substance,” “pollutant,” or “contaminant,” or otherwise classified or regulated or subject to liability in or pursuant to any Environmental Law; or (ii) which is or contains asbestos, polychlorinated biphenyls, radon, urea formaldehyde foam insulation, explosives, or radioactive materials; or (iii) which causes or threatens to cause contamination, nuisance with respect to any properties, or a hazard to the environment or to the health or safety of persons on or about any properties.

“ Indemnity Claim ” has the meaning assigned to such term in Section  9.5 .

“ Knowledge ,” as used in this Agreement with respect to a Party, means the actual knowledge of that Party’s designated personnel.  The designated personnel for the Contributing Parties are James Yardley, James Cleary, J.R. Sult, Katherine Murray, and Thomas Hutchins.  The designated personnel for the Partnership Parties are James Yardley, James Cleary, J.R. Sult, Katherine Murray, and Thomas Hutchins.

“ Lien ” means any mortgage, deed of trust, lien, security interest, pledge, conditional sales contract, charge, right of first refusal, drag-along or tag-along right or other encumbrance.

“ Material Adverse Effect ” means any change, effect, event, occurrence, condition or other circumstance that (a) materially and adversely affects the business, assets, liabilities, properties, financial condition or results of operations of CIG or the Subject Interest, other than any such change, effect, event, occurrence, condition or other circumstance affecting (i) the interstate natural gas transportation industry generally (including any change in the prices of natural gas, natural gas liquids or other hydrocarbon products, industry margins or any regulatory changes or changes in Applicable Law), (ii) the United States or global general market, economic, financial or political conditions or (iii) the transactions contemplated in this Agreement, provided that in the case of clauses (i) and (ii) the impact on CIG is not materially disproportionate to the impact on other large interstate natural gas pipeline companies, or (b) hinders, delays or impedes the ability of any Contributing Party or CIG to perform its obligations under the Agreement or the Contributing Parties Ancillary Documents or to consummate the transactions contemplated by this Agreement or the Contributing Parties Ancillary Documents.

“ Material Contract ” has the meaning assigned to such term in Section  3.12(b) .

“ NGA ” has the meaning assigned to such term in Section  3.15(b) .

“ Notice ” has the meaning assigned to such term in Section  10.2 .

“Operating Company” has the meaning assigned to such term in the preamble.

“ Ownership Percentage ” means with respect to (i) Partnership Parties, 40.0%, and (ii) Contributing Parties, 60.0%.

“ Parties ” has the meaning assigned to such term in the preamble.

“ Partnership ” has the meaning assigned to such term in the preamble.

“ Partnership Agreement ” means the First Amended and Restated Agreement of Limited Partnership of the Partnership, dated November 21, 2007, as amended by Amendment No. 1 dated July 28, 2008.

“ Partnership Ancillary Documents ” means each agreement, document or certificate to be delivered by the Buyer Parties at Closing pursuant to Section  2.3(c) , including the Contribution Agreement.

“ Partnership Indemnified Parties ” has the meaning assigned to such term in Section  9.1 .

“ Partnership Material Adverse Effect ” means any change, effect, event, occurrence, condition or other circumstance that (a) materially and adversely affects the business, assets, liabilities, properties, financial condition or results of operations of any Partnership Party, other than any such change, effect, event, occurrence, condition or other circumstance affecting (i) the interstate natural gas transportation industry generally (including any change in the prices of natural gas, natural gas liquids or other hydrocarbon products, industry margins or any regulatory changes or changes in Applicable Law), (ii) the United States or global general market, economic, financial or political conditions or (iii) the transactions contemplated in this Agreement, provided that in the case of clauses (i) and (ii) the impact on the Partnership Parties is not materially disproportionate to the impact on other large interstate natural gas pipeline companies, or (b) hinders, delays or impedes the ability of any Partnership Party to perform its obligations under this Agreement or the Partnership Ancillary Documents or to consummate the transactions contemplated by this Agreement or any Partnership Ancillary Document.

“ Partnership Parties ” has the meaning assigned to such term in the preamble.

“ Partnership Parties Closing Certificate ” has the meaning assigned to such term in Section  6.2 .

“Permits ” has the meaning assigned to such term in Section  3.11 .

“ Permitted Liens ” means all: (i) to the extent no amounts secured thereby are past due or are being contested in good faith by appropriate proceedings and as to which adequate reserves, if any, have been established, mechanics’, materialmen’s, carriers’, workmen’s, repairmen’s, vendors’, operators’ or other like Liens entered into in the ordinary course of business consistent with past practices, if any, that do not materially detract from the value of or materially interfere with the use of any of CIG’s assets subject thereto; (ii) to the extent no amounts secured thereby are past due or are being contested in good faith by appropriate proceedings, Liens arising under original purchase price conditional sales contracts and equipment leases with third parties entered into in the ordinary course of business consistent with past practices; (iii) title defects, rights of use, rights-of-way, permits, licenses, servitudes, sub-surface leases, grazing rights, logging rights, and easements (including the right to operate and maintain ponds, lakes, waterways, canals, ditches, reservoirs, equipment, pipelines, utility lines, railways, streets, roads and structures on, over or through any of CIG’s assets), if any, that, individually or in the aggregate, do not or would not impair in any material respect the use or occupancy of CIG’s assets, taken as a whole, (iv) Liens for Taxes that are not due and payable, that may thereafter be paid without penalty or are being contested in good faith by appropriate proceedings and as to which adequate reserves, if any, have been established; and (v) liens supporting surety bonds, performance bonds and similar obligations issued in connection with CIG’s businesses.

“ Person ” means an individual or entity, including any partnership, corporation, association, trust, limited liability company, joint venture, unincorporated organization or Governmental Authority.

“ Plans ” has the meaning assigned to such term in Section  3.13 .

“ Reimbursement Obligation ” has the meaning assigned to such term in Section 5.8.

“ SEC ” means the Securities and Exchange Commission.

“ SEC Contract ” has the meaning assigned to such term in Section 3.12(a) .

“ SEC Reports ” has the meaning assigned to such term in Section 3.18 .

“ Subject Interest ” has the meaning assigned to such term in the Recitals.

“ Tax ” means all taxes, however denominated, including any interest, penalties or other additions to tax that may become payable in respect thereof, imposed by any federal, state, local or foreign government or any agency or political subdivision of any such government, which taxes shall include, without limiting the generality of the foregoing, all income or profits taxes (including, but not limited to, federal income taxes and state income taxes), gross receipts taxes, net proceeds taxes, alternative or add-on minimum, sales taxes, use taxes, real property gains or transfer taxes, ad valorem taxes, property taxes, value-added taxes, franchise taxes, production taxes, severance taxes, windfall profit taxes, withholding taxes, payroll taxes, employment taxes, excise taxes and other obligations of the same or similar nature to any of the foregoing.

“ Tax Items ” has the meaning assigned to such term in Section 7.2 .

“ Tax Losses ” has the meaning assigned to such term in Section  7.1 .

“ Tax Return ” means all reports, estimates, declarations of estimated Tax, information statements and returns relating to, or required to be filed in connection with, any Taxes, including information returns or reports with respect to backup withholding and other payments to third parties.

“ Taxing Authority ” means, with respect to any Tax, the governmental body, entity or political subdivision thereof that imposes such Tax, and the agency (if any) charged with the collection of such Tax for such entity or subdivision, including any governmental or quasi-governmental entity or agency that imposes, or is charged with collecting, social security or similar charges or premiums.

“Transfer Taxes” has the meaning assigned to such term in Section 7.4 .

“ WYCO ” means the WYCO Development LLC, a Colorado limited liability company that is a joint venture between CIG and an affiliate of Xcel Energy Inc. in which CIG owns a 50% ownership interest in WYCO and operates certain of WYCO’s assets.

In construing and interpreting this Agreement: (a) the word “includes” and its derivatives means “includes, without limitation” and corresponding derivative expressions; (b) the currency amounts referred to herein, unless otherwise specified, are in United States dollars; (c) whenever this Agreement refers to a number of days, such number shall refer to calendar days unless Business Days are specified; (d) unless otherwise specified, all references in this Agreement to “Article,” “Section,” “Disclosure Schedule,” “Exhibit,” “preamble” or “recitals” shall be references to an Article, Section, Disclosure Schedule, Exhibit, preamble or recitals hereto; (e) whenever the context requires, the words used in this Agreement shall include the masculine, feminine and neuter, as well as the singular and the plural; (f) references to a Party include its permitted successors and assigns; and (g) except as otherwise expressly provided herein, all terms of an accounting or financial nature shall be construed in accordance with GAAP, as in effect from time to time.

At the closing of the transactions contemplated hereby (the “ Closing ”), the Contributing Parties shall contribute the Subject Interest to the Partnership, as more specifically set forth in that certain Contribution, Conveyance and Assumption Agreement to be entered into by and among the Parties at the Closing (the “ Contribution Agreement ”) in substantially the form attached as Exhibit A hereto.

.  The Consideration shall be adjusted downward by the Additional Distribution Amount.

The Contributing Parties hereby jointly represent and warrant to the Partnership Parties as follows:

Except as set forth on Disclosure Schedule  3.3 :