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                                                                    EXHIBIT 10.E


                        PIPELINE COMPANY BORROWER JOINDER

                  Reference is made to the $3,000,000,000 Revolving Credit
Agreement, dated as of April 16, 2003 (as amended, supplemented or otherwise
modified from time to time, the "Credit Agreement"; terms defined therein being
used herein as therein defined), among El Paso Corporation, El Paso Natural Gas
Company, Tennessee Gas Pipeline Company, ANR Pipeline Company, certain banks and
other financial institutions from time to time party thereto, JPMorgan Chase
Bank, as Administrative Agent, ABN AMRO Bank N.V. and Citicorp North America,
Inc., as Co-Document Agents, and Bank of America, N.A. and Credit Suisse First
Boston, as Co-Syndication Agents.

                  The undersigned hereby acknowledges that it has received and
reviewed a copy (in execution form) of the Credit Agreement, and agrees to:

                  (a)      join the Credit Agreement as a Pipeline Company
                           Borrower party thereto;

                  (b)      be bound by all covenants, agreements and
                           acknowledgments attributable to a Borrower in the
                           Credit Agreement, any Note and any other Loan
                           Document to which it is a party; and

                  (c)      perform all obligations required of it by the Credit
                           Agreement, any Note and any other Loan Document to
                           which it is a party.

                  The undersigned hereby represents and warrants that the
representations and warranties with respect to it contained in, or made or
deemed made by it in, Article IV of the Credit Agreement are true and correct on
the date hereof, unless stated to be made on or as of, or to relate to, a
specific date or period other than the date hereof.

                  In connection with the provisions of Section 10.09(d) of the
Credit Agreement, CIG hereby irrevocably appoints CT Corporation System (with an
office on the date hereof at 111 Eighth Avenue, 13th Floor, New York, New York
10011) as its agent to receive on behalf of the undersigned and its property
service of copies of the summons and complaint and any other process which may
be served by the Administrative Agent, any Lender or the holder of any Note in
any action or proceeding in the Supreme Court of the State of New York sitting
in New York County and of the United States District Court of the Southern
District of New York in respect of any action or proceeding arising out of or
relating to the Credit Agreement, the Notes issued pursuant to the Credit
Agreement, and any other Loan Document.

                  THIS JOINDER AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.

                         [Signatures begin on next page]


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                  IN WITNESS WHEREOF, the undersigned has caused this Joinder
Agreement to be duly executed and delivered in New York, New York by its proper
and duly authorized officer as of the 23rd day of December, 2003.

                                        COLORADO INTERSTATE GAS COMPANY


                                        By:         /s/ Greg G. Gruber
                                               ---------------------------------
                                        Name:  Greg G. Gruber
                                        Title: Senior Vice President and Chief
                                               Financial Officer


                                Signature Page 1
                     Pipeline Company Borrower Joinder (CIG)

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ACKNOWLEDGED AND AGREED TO:

EL PASO CORPORATION


By:          /s/ John J. Hopper
       --------------------------------
Name:  John J. Hopper
Title: Vice President and Treasurer



                                Signature Page 2
                     Pipeline Company Borrower Joinder (CIG)