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EXHIBIT 4.A
  EL PASO CORPORATION
 as Issuer
 and
 HSBC BANK USA, NATIONAL ASSOCIATION
 as Trustee
 TWELFTH SUPPLEMENTAL INDENTURE
 Dated as of June 18, 2007
 to
 INDENTURE
 Dated as of May 10, 1999




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TABLE
OF CONTENTS
 PageARTICLE 1Relation to Indenture; DefinitionsSection 1.01. Relation to Indenture
    
    
    2Section 1.02. Definitions
    
    
    2Section 1.03. General References
    
    
    2ARTICLE 2Terms and Issuance of 6.875% Senior Notes due 2014 and 7.000% Senior Notes due 2017Section 2.01. Issue of Notes
    
    
    2Section 2.02. Form of Notes, Authentication Certificate
    
    
    2Section 2.03. Additional Notes
    
    
    2ARTICLE 3MiscellaneousSection 3.01. Certain Trustee Matters
    
    
    3Section 3.02. Continued Effect
    
    
    3Section 3.03. Provisions Binding on Companys Successors
    
    
    3Section 3.04. Governing Law
    
    
    3Section 3.05. Counterparts
    
    
    3Exhibit A-1
    
    A-1-1Exhibit A-2
    
    A-2-1




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TWELFTH SUPPLEMENTAL INDENTURE Supplemental Indenture EL PASO CORPORATION Company HSBC BANK USA, NATIONAL
ASSOCIATION Trustee
 RECITALS OF THE COMPANY
 Indenture Securities
  2014 Notes 2017 Notes Notes




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Relation to Indenture; Definitions
 Relation to Indenture.
 Definitions.
 General References. herein hereof hereunder
 Terms and Issuance
 Issue of Notes
 Form of Notes, Authentication Certificate
 Additional Notes
 2




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Miscellaneous
 Certain Trustee Matters.
 Continued Effect.
 Provisions Binding on Companys Successors.
 Governing Law.
 Counterparts.
 (Signature Pages Follow)
 3




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EL PASO CORPORATIONBy:
    /s/ John J. HopperJohn J. HopperVice President and TreasurerHSBC BANK USA, NATIONAL ASSOCIATION
     as TrusteeBy:
    IllegibleAuthorized Signatory 4




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EXHIBIT A-1
  1
 EL PASO CORPORATION
 6.875% SENIOR NOTE DUE 2014
 NO.
    
    U.S.$CUSIP NO. 28336L BMO
 Company 2
 
 1
    
    Insert in Global Securities only.2
    
    Insert in Global Securities only. A-1-1




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3
 4
  
 3
    
    Insert in Global Securities only.4
    
    Insert in Definitive Securities only. A-1-2




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A-1-3




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Dated:
    EL PASO CORPORATIONBy:Name:Title:  HSBC Bank USA, National 
     Association, as TrusteeBy:Authorized Signatory A-1-4




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El Paso Corporation
6.875% Senior Note due 2014
 Securities Indenture Trustee
 Make-Whole Price
  A-1-5




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A-1-6




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Change of Control Payment Date
        A-1-7




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A-1-8




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A-1-9




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5
 6
     
 5
    
    Insert in Global Securities only.6
    
    Insert in Definitive Securities only. A-1-10




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A-1-11




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Dated:(Signature)
 7
 
 7
    
    Insert in Definitive Securities only. A-1-12




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EXHIBIT A-2
  8
 EL PASO CORPORATION
 7.000% SENIOR NOTE DUE 2017
 NO. 
CUSIP NO. 28336L BQ1
    
    U.S.$
 Company 9
 
 8
    
    Insert in Global Securities only.9
    
    Insert in Global Securities only. A-2-1




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10
 Register.]11
  
 10
    
    Insert in Global Securities only.11
    
    Insert in Definitive Securities only. A-2-2




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A-2-3




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Dated:
    EL PASO CORPORATIONBy:Name:Title:  HSBC Bank USA, National
     Association, as TrusteeBy:Authorized Signatory A-2-4




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El Paso Corporation
7.000% Senior Note due 2017
 Securities Indenture Trustee
 Make-Whole Price
  A-2-5




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A-2-6




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Change of Control Payment Date
        A-2-7




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Section 13(d)(3) of the Securities Exchange Act of 1934, as
amended) other than the Company or one of its subsidiaries; or
       A-2-8




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A-2-9




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12
 13
   
 12
    
    Insert in Global Securities only.13
    
    Insert in Definitive Securities only. A-2-10




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A-2-11




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Dated:(Signature)
 14
 
 14
    
    Insert in Definitive Securities only. A-2-12