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                                                                  EXHIBIT  10.36

                            [ENRON CORP. LETTERHEAD]




October 31, 2001


Northern Border Pipeline Company
1111 South 103rd Street
P.O. Box 3330 (Zip: 68103-0330)
Omaha, Nebraska 68124-1000

Dear Ladies and Gentlemen:

                          GUARANTY T1173F and T1 174F)


As an inducement to Northern Border Pipeline Company (hereinafter "Northern
Border") to grant credit, or assume a credit risk, from time to time, in respect
to transportation of gas by Northern Border pursuant to a U.S. Shippers Service
Agreement T1173F and T1174F (the "Agreement"), which Agreement is identical to
or substantially the same as the copy attached hereto, for the benefit of Enron
North America, Corp. (hereinafter the "Shipper"), Enron Corp. (hereinafter the
"Guarantor"), shall pay to Northern Border promptly when due, or upon demand
thereafter the full amount of all indebtedness due to Northern Border from
Shipper, pursuant to Article 4 of the Agreement (including interest and expenses
of all collection and reasonable counsel's fees incurred by Northern Border by
reason of the default of Shipper), up to an annual aggregate amount of U.S.
$550,000 during each year that the Agreement remains in effect.

This Guaranty by Guarantor shall remain in full force and effect during the term
of the Agreement, and any extension or renewal thereof and thereafter until
Shipper has fully performed all of its obligations under the Agreement. This
Guaranty applies to all successors and/or assigns of Shipper; provided, however,
that in the event Shipper is released pursuant to the Agreement and Northern
Border's FERC Gas Tariff by Northern Border from its obligations under the
Agreement, the Guarantor shall have the right to cancel this Guaranty by written
notice to Northern Border on or after the effective date of such release.

Guarantor waives notice of acceptance hereof and notice of the volumes of gas
transported by Northern Border for the benefit of Shipper, and of the amounts
and terms thereof, and of all defaults or disputes with Shipper, and of the
settlement or adjustment of such defaults or disputes. The Guarantor, without
affecting its liability hereunder in any respect, consents to and waives notice
of all changes of terms, the withdrawal of extension of credit or time to pay,
the release of the whole or any part of the indebtedness, the settlement or
compromise of differences, the acceptance or release of security, the acceptance
of notes, or any other form of obligation for Shipper's indebtedness, and the
demand, protest and notice of protest of such instruments or their endorsements.




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The obligation of the Guarantor is a primary obligation and covers the payment
of all existing and future indebtedness obligations of Shipper to Northern
Border under the Agreement. This obligation shall be enforceable before or after
proceeding against Shipper or against any security held by Northern Border and
shall be effective regardless of the solvency or insolvency of Shipper at any
time, the extension or modification of the indebtedness of Shipper by operation
of law or the subsequent incorporation, reorganization, merger or consolidation
of Shipper or any other change in the composition, nature, personnel or location
of Shipper.

THIS GUARANTY SHALL FOR ALL PURPOSES BE DEEMED TO BE MADE IN, AND SHALL BE
GOVERNED BY, THE LAWS OF THE STATE OF TEXAS. This Guaranty shall be binding upon
Guarantor, its successors and assigns and shall inure to the benefit of Northern
Border, its successors and assigns.

Guarantor reserves to itself all rights, setoffs, counterclaims and other
defenses, if any, which Shipper is or may be entitled to arising from or out of
the Agreement and/or Northern Border's FERC Gas Tariff.

Guarantor's liability under this Guaranty shall be limited to direct, actual,
monetary damages under the Agreement; provided that, in no event will Guarantor
be subject to consequential, exemplary, equitable, loss of profits, tort or any
other damages.

The Guarantor in executing this Guaranty, represents and warrants to Northern
Border that:

         (i)      The Guarantor is a corporation duly organized and existing in
                  good standing and has full power and authority to make and
                  deliver this Guaranty;

         (ii)     The execution and delivery and performance of this Guaranty by
                  the Guarantor has been duly authorized by all necessary action
                  of its directors and shareholders and does not violate the
                  provisions of any presently applicable law or its articles of
                  incorporation or bylaws or constitute a default under any
                  material ("material" for purposes of this representation
                  meaning creating a liability of U.S. $100,000,000 or more)
                  agreement presently binding on it; and

         (iii)    This Guaranty has been duly executed and delivered by the
                  authorized officers of the Guarantor and constitutes its
                  lawful, binding and legally enforceable obligation, except as
                  such enforceability may be limited by the effect of any
                  applicable bankruptcy, insolvency, reorganization, moratorium
                  or similar laws affecting creditors rights generally and by
                  general principles of equity.

IN WITNESS WHEREOF, this Guaranty has been duly executed by Barry J. Schnapper,
Deputy Treasurer of Guarantor this 31st day of October 2001.

"GUARANTOR"

Enron Corp.                                  Attest:




BY:      /s/ Barry J. Schnapper                      /s/ Teresa A. Callahan
     ---------------------------------      -----------------------------------
         Barry J. Schnapper                          Teresa A. Callahan
         Deputy Treasurer                            Assistant Secretary