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November 6, 2000                                                  Exhibit 10.57

Louisville Gas and Electric Company
820 West Broadway
Louisville, KY 40202

Attention:  Mr. J. Clay Murphy

Gentlemen:

     Reference is made to the Transportation Agreement (Agreement) dated March
1, 1995, as amended, between Texas Gas Transmission Corporation (Texas Gas) and
Louisville Gas and Electric Company (LG&E) providing for the transportation of
natural gas by Texas Gas for LG&E.

     Accordingly, Texas Gas and LG&E hereby desire to amend the Agreement
(originally referred to as the 8-year agreement) between them as follows:

     A.   Effective November 1, 2001, ARTICLE II, TRANSPORTATION SERVICE,
Section 2.1 shall be deleted in its entirety and replaced with the following:

          2.1  Subject to the terms and provisions of this Agreement, Customer
agrees to deliver or cause to be delivered to Texas Gas, at the Point(s) of
Receipt in Exhibit "A" hereunder, gas for transportation, and Texas Gas agrees
to receive, transport, and redeliver, at the Point(s) of Delivery in Exhibit "B"
hereunder, equivalent quantities of gas to Customer or for the account of
Customer, in accordance with Section 3 of Texas Gas's effective FT Rate Schedule
and the terms and conditions contained herein, up to 18,000 MMBtu per day, which
shall be Customer's Firm Transportation Contract Demand, and up to 6,570,000
MMBtu during the year, which shall be Customer's Annual Quantity Level.

     B.   ARTICLE V, TERM OF AGREEMENT, shall be deleted in its entirety and
replaced with the following:

          5.1  This Agreement shall become effective upon its execution and
remain in full force and effect with a primary term beginning April 1, 1995,
(with the rates and charges described in Article VIII becoming effective on that
date) and extending through October 31, 2006. At the end of such primary term,
or any subsequent roll-over term, this Agreement shall automatically be extended
for an additional roll-over term of five (5) years, unless Customer terminates
this Agreement at the end of such primary or roll-over term by giving Texas Gas
at least 365 days advance written notice prior to the expiration of the primary
term of any subsequent roll-over term.

          5.2  In the event that any applicable state law, order, or regulation
requires Customer, or permits Customer and Customer so elects, to unbundle its
services at the retail level prior to October 31, 2006, and such unbundling
results in Customer holding Daily Contract Demand and Seasonal Quantity
Entitlements that Customer determines would be in excess of the levels required
to enable Customer to provide service after unbundling, then Texas Gas and
Customer agree to renegotiate this Agreement in good faith to devise terms and
conditions that are mutually acceptable to both parties. Customer shall initiate
such renegotiation as soon as practicable after it becomes aware that retail
unbundling will have a definite effect on this Agreement. Customer shall also
attempt to minimize the extent to which capacity subject to this Agreement
becomes surplus to Customer's requirements by directly assigning any surplus
capacity at prevailing contractual rates to any replacement shipper.

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               If Texas Gas and Customer are unable to successfully renegotiate
this Agreement, and Customer pursues the assignment of surplus capacity
described above, but nonetheless all or part of the capacity reflected in this
Agreement becomes unneeded, then Customer shall have the option to elect to
reduce its Daily Contract Demand and related Seasonal Quantity Entitlements by
an amount determined by Customer to be equal to the capacity which has or will
become unneeded pursuant to any such unbundling of services. If Customer
exercises such reduction option, Customer agrees to provide Texas Gas with
written notice of its election to reduce its Daily Contract Demand and Seasonal
Quantity Entitlements. Such notice shall include a waiver of any right of first
refusal, if any, applicable to the Daily Contract Demand which Customer elects
to reduce. Such reduction shall become effective one (1) year from the first day
of the first month following the receipt of Customer's written notice of its
election to reduce. Nothing herein shall prevent Customer from exercising such
reduction right more than once during the remaining term of this Agreement.

     C.   Effective November 1, 2001, EXHIBIT "C", SUPPLY LATERAL CAPACITY,
shall be deleted in its  entirety and  replaced  with the attached  EXHIBIT "C",
SUPPLY LATERAL CAPACITY.

     The operation of the provisions of this amendment shall be subject to all
applicable governmental statutes and all applicable and lawful orders, rules,
and regulations.

     Except as otherwise provided herein, this amendment shall become effective
on the first day of the month following the date that Customer is notified in
writing by Texas Gas that Customer has been awarded the incremental Winter
Season capacity which is the subject of Paragraph A of this Agreement. If
Customer is not awarded such incremental Winter Season capacity prior to
November 1, 2001, then this Amendment shall be void AB INITIO and of no force
and effect.

     Except as herein amended, the Agreement between the parties hereto shall
remain in full force and effect.

     If the foregoing is in accordance with your understanding of our Agreement,
please execute both copies and return to us. We will, in turn, execute them and
return one copy for your records.

                                            Very truly yours,


LOUISVILLE GAS AND ELECTRIC COMPANY         TEXAS GAS TRANSMISSION CORPORATION


By:   /s/ Rebecca L. Farrar                 By:  /s/ H. Dean Jones II
      ----------------------                     ------------------------------

Title Senior Vice President-Distribution    ATTEST:   /s/ Sherry L. Rice
      -----------------------------------             ------------------
        Operations                                         Asst. Sec.
        ----------

AGREED TO AND ACCEPTED this 20th of November, 2000

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                      ------------------------------------
                              Contract No. T006487
                      ------------------------------------

                               Firm Transportation
                                    Agreement
                                    Exhibit C
                             Supply Lateral Capacity

                      Louisville Gas and Electric Company

<Table>
<Caption>
                                                                      Preferential rights
                                                                            MMBtu/d

                                      Supply Lateral                 WINTER           SUMMER
                                                                     ------           ------
<S>                                                                    <C>               <C>
ZONE 1 SUPPLY LATERAL(S)

North Louisiana Leg:                                                    9,164            12,237
                                                              ---------------------------------
                  Total Zone 1:                                         9,164            12,237

ZONE SL SUPPLY LATERAL(S)

East Leg:                                                                 145             4,047
Southeast Leg:                                                          6,092            21,885
South Leg:                                                              1,703             4,727
Southwest Leg:                                                          1,464            16,953
West Leg:                                                                 152               232
WC-294 (at ANR-Eunice)                                                      0             8,221
HIOS (at ANR-Eunice)                                                        0             4,933
                                                              ---------------------------------
                  Total Zone SL:                                        9,556            60,998
                                                              ---------------------------------
                  Grand Total:                                         18,720            73,235
                                                              =================================
</Table>

This exhibit reflects the combined total contractual quantities for LG&E under
the 2, 5, and 8-year agreements for the subject contract. Amendments in contract
quantities in any of these three agreements will result in an amendment of this
exhibit.

Effective Date: November 1, 2001