<PAGE>

                                                                 EXHIBIT 4(a)(4)

                                     FORM OF

                          SUPPLEMENTAL TRUST INDENTURE

                                      FROM

                          NORTHERN STATES POWER COMPANY
                            (A MINNESOTA CORPORATION)

                                       TO

                            BNY MIDWEST TRUST COMPANY

                               -------------------

                          DATED [__________], [_______]

                               -------------------

                         SUPPLEMENTAL TO TRUST INDENTURE
                             DATED FEBRUARY 1, 1937

                                       AND

                            SUPPLEMENTAL AND RESTATED
                                 TRUST INDENTURE
                                DATED MAY 1, 1988

<PAGE>

                                TABLE OF CONTENTS

<TABLE>
<S>                                                                             <C>
PARTIES         ...........................................................      1

RECITALS        ...........................................................      1

                                    ARTICLE I
                  SPECIFIC SUBJECTION OF ADDITIONAL PROPERTY TO
                       THE LIEN OF THE ORIGINAL INDENTURE

SECTION 1.01    ...........................................................      9

                                   ARTICLE II
                    FORM AND EXECUTION OF SERIES DUE [______]

SECTION 2.01    ...........................................................     11

SECTION 2.02    ...........................................................     12

SECTION 2.03    ...........................................................     13

SECTION 2.04    ...........................................................     13

SECTION 2.05    ...........................................................     13

SECTION 2.06    ...........................................................     13

                                   ARTICLE III
                                  [SINKING FUND

SECTION 3.01    ...........................................................     16

SECTION 3.02    ...........................................................     18

SECTION 3.03    ...........................................................     18]

                                   ARTICLE IV
                       APPOINTMENT OF AUTHENTICATING AGENT

SECTION 4.01    ...........................................................     19

SECTION 4.02    ...........................................................     19

SECTION 4.03    ...........................................................     20

SECTION 4.04    ...........................................................     20

                                    ARTICLE V
                       FINANCING STATEMENT TO COMPLY WITH
                           THE UNIFORM COMMERCIAL CODE

SECTION 5.01    ...........................................................     20

SECTION 5.02    ...........................................................     21

SECTION 5.03    ...........................................................     21

SECTION 5.04    ...........................................................     21
</TABLE>

                                       i

<PAGE>

<TABLE>
<S>                                                                             <C>
SECTION 5.05    ...........................................................     21

SECTION 5.06    ...........................................................     25

                                   ARTICLE VI
                             AMENDMENTS TO INDENTURE

SECTION 6.01    ...........................................................     25

                                   ARTICLE VII
                                  MISCELLANEOUS

SECTION 7.01    ...........................................................     25

SECTION 7.02    ...........................................................     26

SECTION 7.03    ...........................................................     26

SECTION 7.04    ...........................................................     26

SECTION 7.05    ...........................................................     26

SECTION 7.06    ...........................................................     26
</TABLE>

Schedule A - Properties

                                       ii

<PAGE>

         Supplemental Trust Indenture, made effective as of the [_______] day of
[_______], [_______], by and between NORTHERN STATES POWER COMPANY (formerly
Northern Power Corporation), a corporation duly organized and existing under and
by virtue of the laws of the State of Minnesota, having its principal office in
the County of Minneapolis, Minnesota (the "Company"), party of the first part,
and BNY MIDWEST TRUST COMPANY, a corporation duly organized and existing under
and by virtue of the laws of the State of Illinois, having its principal office
in the City of Chicago, Illinois (as successor Trustee to Harris Trust and
Savings Bank) (the "Trustee"), party of the second part;

WITNESSETH:

         WHEREAS, a predecessor in interest to the Company, Xcel Energy Inc.
(formerly Northern States Power Company), a corporation duly organized and
existing under and by virtue of the laws of the State of Minnesota (the
"Predecessor Company") has heretofore executed and delivered to the Trustee its
Trust Indenture (the "1937 Indenture"), made as of February 1, 1937, whereby the
Predecessor Company granted, bargained, sold, warranted, released, conveyed,
assigned, transferred, mortgaged, pledged, set over and confirmed to the Trustee
and to its respective successors in trust, all property, real, personal and
mixed then owned or thereafter acquired or to be acquired by the Predecessor
Company (except as therein excepted from the lien thereof) and subject to the
rights reserved by the Predecessor Company in and by the provisions of the 1937
Indenture, to be held by said Trustee in trust in accordance with the provisions
of the 1937 Indenture for the equal pro rata benefit and security of all and
each of the bonds issued and to be issued thereunder in accordance with the
provisions thereof; and

         WHEREAS, the Predecessor Company heretofore has executed and delivered
to the Trustee a Supplemental Trust Indenture, made as of June 1, 1942, whereby
the Predecessor Company conveyed, assigned, transferred, mortgaged, pledged, set
over, and confirmed to the Trustee, and its respective successors in said trust,
additional property acquired by it subsequent to the date of the 1937 Indenture;
and

         WHEREAS, the Predecessor Company prior to August 1, 2000, and
thereafter, the Company, heretofore has executed and delivered to the Trustee
the following additional Supplemental Trust Indentures which, in addition to
conveying, assigning, transferring, mortgaging, pledging, setting over, and
confirming to the Trustee, and its respective successors in said trust,
additional property acquired by it subsequent to the preparation of the next
preceding Supplemental Trust Indenture and adding to the covenants, conditions,
and agreements of the 1937 Indenture certain additional covenants, conditions,
and agreements to be observed by the Company, created the following series of
First Mortgage Bonds:

<TABLE>
<CAPTION>
DATE OF SUPPLEMENTAL
  TRUST INDENTURE                             DESIGNATION OF SERIES
--------------------               -------------------------------------------
<S>                                <C>
February 1, 1944                   Series due February 1, 1974 (retired)
October 1, 1945                    Series due October 1, 1975 (retired)
July 1, 1948                       Series due July 1, 1978 (retired)
August 1, 1949                     Series due August 1, 1979 (retired)
</TABLE>

                                      -1-

<PAGE>

<TABLE>
<CAPTION>
 DATE OF SUPPLEMENTAL
   TRUST INDENTURE                            DESIGNATION OF SERIES
---------------------              -------------------------------------------
<S>                                <C>
June 1, 1952                       Series due June 1, 1982 (retired)
October 1, 1954                    Series due October 1, 1984 (retired)
September 1, 1956                  Series due 1986 (retired)
August 1, 1957                     Series due August 1, 1987 (redeemed)
July 1, 1958                       Series due July 1, 1988 (retired)
December 1, 1960                   Series due December 1, 1990 (retired)
August 1, 1961                     Series due August 1, 1991 (retired)
June 1, 1962                       Series due June 1, 1992 (retired)
September 1, 1963                  Series due September 1, 1993 (retired)
August 1, 1966                     Series due August 1, 1996 (redeemed)
June 1, 1967                       Series due June 1, 1995 (redeemed)
October 1, 1967                    Series due October 1, 1997 (redeemed)
May 1, 1968                        Series due May 1, 1998 (redeemed)
October 1, 1969                    Series due October 1, 1999 (redeemed)
February 1, 1971                   Series due March 1, 2001 (redeemed)
May 1, 1971                        Series due June 1, 2001 (redeemed)
February 1, 1972                   Series due March 1, 2002 (redeemed)
January 1, 1973                    Series due February 1, 2003 (redeemed)
January 1, 1974                    Series due January 1, 2004 (redeemed)
September 1, 1974                  Pollution Control Series A (redeemed)
April 1, 1975                      Pollution Control Series B (redeemed)
May 1, 1975                        Series due May 1, 2005 (redeemed)
March 1, 1976                      Pollution Control Series C (retired)
June 1, 1981                       Pollution Control Series D, E and F
                                   (redeemed)
December 1, 1981                   Series due December 1, 2011 (redeemed)
May 1, 1983                        Series due May 1, 2013 (redeemed)
December 1, 1983                   Pollution Control Series G (redeemed)
September 1, 1984                  Pollution Control Series H (redeemed)
December 1, 1984                   Resource Recovery Series I (redeemed)
May 1, 1985                        Series due June 1, 2015 (redeemed)
September 1, 1985                  Pollution Control Series J, K and L
July 1, 1989                       Series due July 1, 2019 (redeemed)
June 1, 1990                       Series due June 1, 2020 (redeemed)
October 1, 1992                    Series due October 1, 1997 (retired)
April 1, 1993                      Series due April 1, 2003 (retired)
December 1, 1993                   Series due December 1, 2000 (retired), and
                                   December 1, 2005
February 1, 1994                   Series due February 1, 1999 (retired)
October 1, 1994                    Series due October 1, 2001 (retired)
June 1, 1995                       Series due July 1, 2025
April 1, 1997                      Pollution Control Series M (redeemed), N, O
                                   and P
March 1, 1998                      Series due March 1, 2003 (retired), and
</TABLE>

                                      -2-

<PAGE>

<TABLE>
<CAPTION>
 DATE OF SUPPLEMENTAL
   TRUST INDENTURE                            DESIGNATION OF SERIES
---------------------              -------------------------------------------
<S>                                <C>
                                   March 1, 2028
May 1, 1999                        Resource Recovery Series Q
June 1, 2000                       Resource Recovery Series R
June 1, 2002                       Series due August 15, 2003
July 1, 2002                       Pollution Control Series S
August 1, 2002                     Series due August 28, 2012; and
</TABLE>

         WHEREAS, on August 18, 2000 New Centuries Energies, Inc. was merged
with and into the Predecessor Company and the Predecessor Company changed its
corporate name from Northern States Power Company to Xcel Energy Inc.; and

         WHEREAS, pursuant to an Assignment and Assumption Agreement dated as of
August 18, 2000 between the Predecessor Company and the Company, substantially
all the assets of the Predecessor Company (other than the stock of the
Predecessor Company's subsidiaries) were conveyed to, and substantially all the
liabilities of the Predecessor Company, including liabilities created under the
Indenture, were assumed by, the Company (the "Assignment"); and

         WHEREAS, pursuant to the Supplemental Trust Indenture dated as of
August 1, 2000 among the Predecessor Company, the Company and Harris Trust and
Savings Bank, as Trustee, the requirements and conditions precedent set forth in
the Original Indenture and the Restated Indenture (each as hereinafter defined)
with respect to the Assignment were satisfied; and

         WHEREAS, the 1937 Indenture and all of the foregoing Supplemental Trust
Indentures are referred to herein collectively as the "Original Indenture"; and

         WHEREAS, the Predecessor Company heretofore has executed and delivered
to the Trustee a Supplemental and Restated Trust Indenture, dated May 1, 1988
(the "Restated Indenture"), which, in addition to conveying, assigning,
transferring, mortgaging, pledging, setting over, and confirming to the Trustee,
and its respective successors in said trust additional property acquired by it
subsequent to the preparation of the next preceding Supplemental Trust
Indenture, amended and restated the Original Indenture (except for those
Supplemental Trust Indentures executed after May 1, 1988); and

         WHEREAS, the Restated Indenture will not become effective and operative
until all bonds of each series issued under the Original Indenture prior to May
1, 1988, shall have been retired through payment or redemption (including those
bonds "deemed to be paid" within the meaning of that term as used in Article
XVIII of the 1937 Indenture) or until, subject to certain exceptions, the
holders of the requisite principal amount of such bonds shall have consented to
the amendments contained in the Restated Indenture (such date being herein
called the "Effective Date"); and

         WHEREAS, the Original Indenture and the Restated Indenture are referred
to herein collectively as the "Indenture"; and

                                      -3-

<PAGE>

         WHEREAS, pursuant to the Agreement of Resignation, Appointment and
Acceptance dated as of May 1, 2002 among the Company, BNY Midwest Trust Company,
as successor trustee, and Harris Trust and Savings Bank, the Trustee accepted
the rights, powers, duties and obligations of the trustee under the Indenture
effective as of May 9, 2002; and

         WHEREAS, the Indenture provides that bonds may be issued thereunder in
one or more series, each series to have such distinctive designation as the
Board of Directors of the Company may select for such series; and

         WHEREAS, the Company is desirous of providing for the creation of a new
series of First Mortgage Bonds, said new series of bonds to be designated "First
Mortgage Bonds, Series due [_______]", the bonds of such series to be issued as
registered bonds without coupons in denominations of a multiple of $1,000, and
the bonds of such series to be substantially in the form and of the tenor
following [with the redemption prices inserted therein in conformity with the
provisions of Section 2.02 hereof,] to-wit:

                     (Form of Bonds of Series due [_______])
                          NORTHERN STATES POWER COMPANY
             (Incorporated under the laws of the State of Minnesota)
                               First Mortgage Bond
                              Series Due [_______]

No. _______________                                           $________________

         [Unless this certificate is presented by an authorized representative
of The Depository Trust Company, a New York corporation, to the Company or its
agent for registration of transfer, exchange or payment, and any certificate
issued is registered in the name of Cede & Co. or such other name as is
requested by an authorized representative of The Depository Trust Company (and
any payment is made to Cede & Co. or to such other entity as is requested by an
authorized representative of The Depository Trust Company), ANY TRANSFER, PLEDGE
OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL since
the registered owner hereof, Cede & Co., has an interest herein.]*

         NORTHERN STATES POWER COMPANY, a corporation organized and existing
under the laws of the State of Minnesota (the "Company"), for value received,
hereby promises to pay to [_____________] or its registered assigns, at the
office of the Trustee, in Chicago, Illinois, or, at the option of the registered
owner, at the agency of the Company in the Borough of Manhattan, City and State
of New York, an amount equal to [_________] Dollars in lawful money of the
United States of America, on the [_______] day of [_______], [_______], and to
pay interest hereon from the date hereof at the rate of [_______] percent per
annum, in like money, until the Company's obligation with respect to the payment
of such principal sum shall be discharged; said interest being payable at the
option of the person entitled to such interest either at the office of the
Trustee, in Chicago, Illinois, or at the agency of the Company in the Borough of
Manhattan, City and State of New York, on the [_______] day of [_______]and on
the [_______] day of [_______] in each year provided that as long as there is no
existing default in the payment of interest and except for the payment of
defaulted interest, the interest payable

*This legend to be included if the bonds are issued as a global bond in
book-entry form.

                                       -4-

<PAGE>

on any [_______] or [_______] will be paid to the person in whose name this bond
was registered at the close of business on the record date (the [_______] prior
to such [_______] or the [_______] prior to such [_______] (whether or not a
business day)).

         [EXCEPT UNDER THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE,
THESE GLOBAL BONDS MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE REGISTERED
DEPOSITORY OR BY A NOMINEE OF THE REGISTERED DEPOSITORY TO THE REGISTERED
DEPOSITORY, ANOTHER NOMINEE OF THE REGISTERED DEPOSITORY, A SUCCESSOR OF THE
REGISTERED DEPOSITORY OR A NOMINEE OF SUCH SUCCESSOR.]*

         This bond is one of a duly authorized issue of bonds of the Company, of
the series and designation indicated on the face hereof, which issue of bonds
consists, or may consist, of several series of varying denominations, dates, and
tenor, all issued and to be issued under and equally secured (except insofar as
a sinking fund, or similar fund, established in accordance with the provisions
of the Indenture may afford additional security for the bonds of any specific
series) by a Trust Indenture dated February 1, 1937 (the "1937 Indenture"), as
supplemented by ___ supplemental trust indentures (collectively, the
"Supplemental Indentures"), a Supplemental and Restated Trust Indenture dated
May 1, 1988 (the "Restated Indenture") and a new supplemental trust indenture
for the bonds of this series (the "New Supplemental Indenture"), executed by the
Company to BNY MIDWEST TRUST COMPANY (as successor trustee to Harris Trust and
Savings Bank) (the "Trustee"). The 1937 Indenture, as supplemented by the
Supplemental Indentures, the Restated Indenture and the New Supplemental
Indenture is referred to herein as the "Indenture". Reference hereby is made to
the Indenture for a description of the property mortgaged and pledged, the
nature and extent of the security, the rights of the holders of the bonds as to
such security, and the terms and conditions upon which the bonds may be issued
under the Indenture and are secured. The principal hereof may be declared or may
become due on the conditions, in the manner and at the time set forth in the
Indenture upon the happening of a default as provided in the Indenture.

         With the consent of the Company and to the extent permitted by and as
provided in the Indenture, the rights and obligations of the Company and of the
holders of the bonds, and the terms and provisions of the Indenture and of any
instruments supplemental thereto may be modified or altered by affirmative vote
of the holders of at least 66 2/3% in principal amount of the bonds then
outstanding under the Indenture and any instruments supplemental thereto
(excluding bonds challenged and disqualified from voting by reason of the
Company's interest therein as provided in the Indenture); provided that without
the consent of all holders of all bonds affected no such modification or
alteration shall permit the extension of the maturity of the principal of any
bond or the reduction in the rate of interest thereon or any other modification
in the terms of payment of such principal or interest.

         The Restated Indenture amends and restates the 1937 Indenture and the
Supplemental Indentures executed prior to May 1, 1988. The Restated Indenture
will become effective and operative (the "Effective Date") when all bonds of
each series issued under the Indenture prior to

*This legend to be included if the bonds are issued as a global bond in
book-entry form.

                                       -5-

<PAGE>


May 1, 1988 shall have been retired through payment or redemption (including
those bonds "deemed to be paid" within the meaning of that term as used in
Article XVII of the 1937 Indenture) or until, subject to certain exceptions, the
holders of the requisite principal amount of such bonds shall have consented to
the amendments contained in the Restated Indenture. Holders of the bonds of this
series and of each subsequent series of bonds issued under the Indenture
likewise will be bound by the amendments contained in the Restated Indenture
when they become effective and operative. Reference is made to the Restated
Indenture for a complete description of the amendments contained therein to the
1937 Indenture and to the Supplemental Indentures.

         The Company and the Trustee may deem and treat the person in whose name
this bond is registered as the absolute owner hereof for the purpose of
receiving payment and for all other purposes and shall not be affected by any
notice to the contrary.

         [At the option of the Company, and upon not less than 30 days' notice
prior to the date fixed for redemption, in the manner and with the effect
provided in the Indenture, any or all of the bonds of this Series due [______],
may be redeemed, [other than for the Sinking Fund provided for bonds of this
series,] by the Company on any date by the payment of

                  [REDEMPTION TERMS ARE TO BE INSERTED IN EACH BOND IN
                  CONFORMITY WITH THE PROVISIONS OF SECTION 2.02]]

         [Bonds of this series are not redeemable prior to maturity, for any
reason, and are not subject to a sinking fund.]

         This bond is transferable as prescribed in the Indenture by the
registered owner hereof in person, or by his duly authorized attorney, at the
office of the Trustee in Chicago, Illinois, or at the option of the owner at the
agency of the Company in the Borough of Manhattan, City and State of New York,
or elsewhere if authorized by the Company, upon surrender and cancellation of
this bond, and thereupon a new bond or bonds of the same series and of a like
aggregate principal amount will be issued to the transferee in exchange therefor
as provided in the Indenture, upon payment of taxes or other governmental
charges, if any, that may be imposed in relation thereto.

         Bonds of this series are interchangeable as to denominations in the
manner and upon the conditions prescribed in the Indenture.

                                      -6-

<PAGE>

         No charge shall be made by the Company for any exchange or transfer of
bonds of this Series due [______], other than for taxes or other governmental
charges, if any, that may be imposed in relation thereto.

         No recourse shall be had for the payment of the principal of or the
interest on this bond, or any part thereof, or of any claim based hereon or in
respect hereof or of said Indenture, against any incorporator, or any past,
present, or future shareholder, officer or director of the Company or of any
predecessor or successor corporation, either directly or through the Company, or
through any such predecessor or successor corporation, or through any receiver
or a trustee in bankruptcy, whether by virtue of any constitution, statute, or
rule of law or by the enforcement of any assessment or penalty or otherwise, all
such liability being, by the acceptance hereof and as part of the consideration
for the issue hereof, expressly waived and released, as more fully provided in
the Indenture.

         This bond shall not be valid or become obligatory for any purpose
unless and until the certificate of authentication hereon shall have been signed
by or on behalf of BNY Midwest Trust Company (as successor trustee to Harris
Trust and Savings Bank), as Trustee under the Indenture, or its successor
thereunder.

         IN WITNESS WHEREOF, NORTHERN STATES POWER COMPANY has caused this bond
to be executed in its name by its President or a Vice President and its
corporate seal, or a facsimile thereof, to be hereto affixed and attested by its
Secretary or an Assistant Secretary.

Dated: [________]                            NORTHERN STATES POWER
                                             COMPANY

       Attest:____________________           By:_________________________
              Secretary                         President

                                      -7-

<PAGE>

                         (Form of Trustee's Certificate)

         This bond is one of the bonds of the Series designated thereon,
described in the within-mentioned Indenture.

                                             BNY MIDWEST TRUST COMPANY, as
                                             Trustee

                                             By:________________________
                                                   Authorized Officer

                                      -8-

<PAGE>

and

         WHEREAS, the Company is desirous of conveying, assigning, transferring,
mortgaging, pledging, setting over, and confirming to the Trustee and to its
respective successors in trust, additional property acquired by it subsequent to
the date of the preparation of the Supplemental Trust Indenture dated as of
[______]; and

         WHEREAS, the Indenture provides in substance that the Company and the
Trustee may enter into indentures supplemental thereto for the purposes, among
others, of creating and setting forth the particulars of any new series of bonds
and of providing the terms and conditions of the issue of the bonds of any
series not expressly provided for in the Indenture and of conveying, assigning,
transferring, mortgaging, pledging, setting over and confirming to the Trustee
additional property of the Company, and for any other purpose not inconsistent
with the terms of the Indenture; and

         WHEREAS, the execution and delivery of this Supplemental Trust
Indenture have been duly authorized by a resolution adopted by the Board of
Directors of the Company;

         WHEREAS, the Trustee has duly determined to execute this Supplemental
Trust Indenture and to be bound, insofar as it may lawfully do so, by the
provisions hereof;

         NOW, THEREFORE, Northern States Power Company, in consideration of the
premises and of one dollar duly paid to it by the Trustee at or before the
ensealing and delivery of these presents, the receipt of which is hereby
acknowledged, and other good and valuable considerations, does hereby covenant
and agree to and with BNY Midwest Trust Company (as successor trustee to Harris
Trust and Savings Bank), as Trustee, and its successors in the trust under the
Indenture for the benefit of those who hold or shall hold the bonds, or any of
them, issued or to be issued thereunder, as follows:

                                   ARTICLE I
                  SPECIFIC SUBJECTION OF ADDITIONAL PROPERTY TO
                       THE LIEN OF THE ORIGINAL INDENTURE

         SECTION 1.01.     The Company in order to better secure the payment, of
both the principal and interest, of all bonds of the Company at any time
outstanding under the Indenture according to their tenor and effect and the
performance of and compliance with the covenants and conditions contained in the
Indenture, has granted, bargained, sold, warranted, released, conveyed,
assigned, transferred, mortgaged, pledged, set over, and confirmed and by these
presents does grant, bargain, sell, warrant, release, convey, assign, transfer,
mortgage, pledge, set over, and confirm to the Trustee and to its respective
successors in said trust forever, subject to the rights reserved by the Company
in and by the provisions of the Indenture, all of the property described and
mentioned or enumerated in a schedule annexed hereto and marked Schedule A,
reference to said schedule being made hereby with the same force and effect as
if the same were incorporated herein at length; together with all and singular
the tenements, hereditaments, and appurtenances belonging and in any way
appertaining to the aforesaid property or any part thereof with the reversion
and reversions, remainder and remainders, tolls, rents and revenues, issues,
income, products, and profits thereof;

                                      -9-

<PAGE>

         Also, in order to subject the personal property and chattels of the
Company to the lien of the Indenture and to conform with the provisions of the
Uniform Commercial Code, all fossil, nuclear, hydro, and other electric
generating plants, including buildings and other structures, turbines,
generators, exciters, boilers, reactors, nuclear fuel, other boiler plant
equipment, condensing equipment and all other generating equipment; substations;
electric transmission and distribution systems, including structures, poles,
towers, fixtures, conduits, insulators, wires, cables, transformers, services
and meters; steam heating mains and equipment; gas transmission and distribution
systems, including structures, storage facilities, mains, compressor stations,
purifier stations, pressure holders, governors, services, and meters; telephone
plant and related distribution systems; trucks and trailers; office, shop, and
other buildings and structures, furniture and equipment; apparatus and equipment
of all other kinds and descriptions; materials and supplies; all municipal and
other franchises, leaseholds, licenses, permits, privileges, patents and patent
rights; all shares of stock, bonds, evidences of indebtedness, contracts,
claims, accounts receivable, choses in action and other intangibles, all books
of account and other corporate records;

         Excluding, however, all merchandise and appliances heretofore or
hereafter acquired for the purpose of sale to customers and others;

         All the estate, right, title, interest, and claim, whatsoever, at law
as well as in equity which the Company now has or hereafter may acquire in and
to the aforesaid property and every part and parcel thereof subject, however, to
the right of the Company, until the happening of a completed default as defined
in Section 1 of Article XIII of the Original Indenture prior to the Effective
Date and upon the occurrence and continuation of a Completed Default as defined
in the Indenture on and after the Effective Date, to retain in its possession
all shares of stock, notes, evidences of indebtedness, other securities and cash
not expressly required by the provisions hereof to be deposited with the
Trustee, to retain in its possession all contracts, bills and accounts
receivable, motor cars, any stock of goods, wares and merchandise, equipment or
supplies acquired for the purpose of consumption in the operation, construction,
or repair of any of the properties of the Company, and to sell, exchange,
pledge, hypothecate, or otherwise dispose of any or all of such property so
retained in its possession free from the lien of the Indenture, without
permission or hindrance on the part of the Trustee, or any of the bondholders.
No person in any dealings with the Company in respect of any such property shall
be charged with any notice or knowledge of any such completed default (prior to
the Effective Date) or Completed Default (after the Effective Date) under the
Indenture while the Company is in possession of such property. Nothing contained
herein or in the Indenture shall be deemed or construed to require the deposit
with, or delivery to, the Trustee of any of such property, except such as is
specifically required to be deposited with the Trustee by some express provision
of the Indenture;

         To have and to hold all said property, real, personal, and mixed,
granted, bargained, sold, warranted, released, conveyed, assigned, transferred,
mortgaged, pledged, set over, or confirmed by the Company as aforesaid, or
intended so to be, to the Trustee and its successors and assigns forever,
subject, however, to permitted liens as defined in Section 5 of Article I of the
1937 Indenture prior to the Effective Date and to Permitted Encumbrances on and
after the Effective Date and to the further reservations, covenants, conditions,
uses, and trusts set forth in the

                                      -10-

<PAGE>

Indenture; in trust nevertheless for the same purposes and upon the same
conditions as are set forth in the Indenture.

                                   ARTICLE II
                   FORM AND EXECUTION OF SERIES DUE [_______]

         SECTION 2.01.     There is hereby created, for issuance under the
Indenture, a series of bonds designated Series due [______], each of which shall
bear the descriptive title "First Mortgage Bonds, Series due [______]", and the
form thereof shall contain suitable provisions with respect to the matters
hereafter specified in this Section. The bonds of said series shall be
substantially of the tenor and purport hereinbefore recited. The bonds of said
series shall mature [_______], and shall be issued as registered bonds without
coupons in denominations of $1,000. The bonds of said series shall bear interest
at a rate of [_______]% per annum payable semi-annually on [_______] and
[_______] of each year, and the principal shall be payable at the office of the
Trustee in Chicago, Illinois, or at the option of the registered owner at the
agency of the Company in the Borough of Manhattan, City and State of New York,
in lawful money of the United States of America, and the interest shall be
payable in like money at the option of the person entitled to such interest
either at said office of the Trustee in Chicago, Illinois, or at the agency of
the Company in the Borough of Manhattan, City and State of New York. Bonds of
the Series due [_______] shall be dated as of the interest payment date next
preceding the authentication thereof by the Trustee except that (i) if any bond
shall be authenticated before [_______], it shall be dated as of [_______],
unless (iii) below is applicable, (ii) if the Company shall at the time of the
authentication of the bond of the Series due [_______] be in default in the
payment of interest upon the bonds of the Series due [_______], such bond shall
be dated as of the date of the beginning of the period for which such interest
is so in default, and (iii) as long as there is no existing default in the
payment of interest on the bonds of the Series due [_______], if any bond of the
Series due [_______] shall be authenticated after the close of business on any
Record Date but on or prior to the interest payment date relating to such Record
Date, it shall be dated as of such interest payment date.

         As long as there is no existing default in the payment of interest on
the bonds of a Series due [_______], the person in whose name any bond of the
Series due [_______] is registered at the close of business on any Record Date
with respect to any interest payment date shall be entitled to receive the
interest payable on such interest payment date notwithstanding any transfer or
exchange of any such bond of the Series due [_______] subsequent to the Record
Date and on or prior to such interest payment date, except as and to the extent
the Company shall default in the payment of the interest due on such interest
payment date, in which case such defaulted interest shall be paid to the person
in whose name such bond of the Series due [_______] is registered on the Special
Record Date for the payment of such defaulted interest to be fixed by the
Trustee, notice thereof shall be given to the registered holder of any bond of
the Series due [_______] not less than 10 days prior to such Special Record
Date, or may be paid at any time in any other lawful manner not inconsistent
with the requirements of any securities exchange on which the bonds of the
Series due [_______] may be listed, and upon such notice as may be required by
such exchange.

         The term "Record Date" as used herein with respect to any interest
payment date ([_______] or [_______]) shall mean the [_______] prior to such
[_______] or [_______] prior

                                      -11-

<PAGE>

to such [_______] (whether or not a business day). The term "business day" shall
mean any day other than a Saturday or Sunday or a day on which the offices of
the Trustee in the City of Chicago, Illinois, are closed pursuant to
authorization of law.

         As used in this Section 2.01, the term "default in the payment of
interest" means failure to pay interest on the applicable interest payment date
disregarding any period of grace permitted by the Indenture.

         The "Special Record Date" as used herein shall be fixed in the
following manner. The Company shall notify the Trustee in writing of the amount
of defaulted interest proposed to be paid on each bond of Series due [_______],
and the date of the proposed payment, and at the same time the Company shall
deposit with the Trustee an amount of money equal to the aggregate amount
proposed to be paid in respect of such defaulted interest or shall make
arrangements satisfactory to the Trustee for such deposit prior to the date of
the proposed payment, such money when deposited to be held in trust for the
benefit of the persons entitled to such defaulted interest as provided in this
Section 2.01. Thereupon the Trustee shall fix a Special Record Date for the
payment of such defaulted interest which shall be not more than 15 nor less than
10 days prior to the date of the proposed payment and not less than 10 days
after the receipt by the Trustee of the notice of the proposed payment. The
Trustee shall promptly notify the Company of such Special Record Date and, in
the name and at the expense of the Company, shall cause notice of the proposed
payment of such defaulted interest and the Special Record Date therefor to be
mailed, first class postage prepaid, to each holder of the bonds of the relevant
Series due [_______], at his, her or its address as it appears in the bond
register, not less than 10 days prior to such Special Record Date. Notice of the
proposed payment of such defaulted interest and the Special Record Date therefor
having been mailed as aforesaid, such defaulted interest shall be paid to the
persons in whose names the bonds of the relevant Series due [_______] are
registered on such Special Record Date and shall not be payable pursuant to the
paragraph immediately following in this Section 2.01.

         The Company may make payment of any defaulted interest in any other
lawful manner not inconsistent with the requirements of any securities exchange
on which the bonds of the relevant Series due [_______] may be listed, and upon
such notice as may be required by such exchange, if, after notice is given by
the Company to the Trustee of the proposed payment pursuant to this Section
2.01, such payment shall be deemed practicable by the Trustee.

         SECTION 2.02.     [The bonds of Series due [_______], shall be
redeemable, [other than for the Sinking Fund for bonds of that series provided
for in Article III hereof,] at the option of the Company as a whole or in part
on any date upon not less than 30 days' previous notice to be given in the
manner and with the effect provided in Section 2 of Article X of the 1937
Indenture (except that, on and after the Effective Date, such notice shall be
given in the manner and effect provided in Section 10.02 of the Indenture) at
the principal amount thereof, with accrued interest thereon to the date of
redemption and at [insert redemption terms].

         The redemption prices of the bonds of the Series due [_______] need not
be specified in any temporary bond of said series if an appropriate reference be
made in said temporary bond to the provision of this Section.]

                                      -12-

<PAGE>

         [The bonds of the Series due [_______] are not redeemable prior to
maturity for any reason and are not subject to a sinking fund.]

         SECTION 2.03.     The registered owner of any bond or bonds of Series
due [_______], at his, her, or its option, may surrender the same with other
bonds of such series at the office of the Trustee in Chicago, Illinois, or at
the agency of the Company in the Borough of Manhattan, City and State of New
York, or elsewhere if authorized by the Company, for cancellation, in exchange
for other bonds of such series of higher or lower authorized denominations, but
of the same aggregate principal amount, bearing interest from its date, and upon
receipt of any payment required under the provisions of Section 2.04 hereof.
Thereupon the Company shall execute and deliver to the Trustee and the Trustee
shall authenticate and deliver such other registered bonds to such registered
owner at its office or at any other place specified as aforesaid.

         [Notwithstanding the provisions of Section 11 of Article II of the 1937
Indenture, the Company shall not be required to issue, transfer or exchange any
bond of the Series due [_______] during a period of ten (10) days next preceding
any selection of bonds of the Series due [_______] to be redeemed. The Company
shall not be required to transfer or exchange any bond of the Series due
[_______] called or being called for redemption in its entirety or to transfer
or exchange the called portion of a bond of the Series due [_______] which has
been called for partial redemption.]

         SECTION 2.04.     No charge shall be made by the Company for any
exchange or transfer of bonds of the Series due [_______], other than for taxes
or other governmental charges, if any, that may be imposed in relation thereto.

         SECTION 2.05.     The bonds of the Series due [_______] shall be
executed on behalf of the Company by the manual signature of its President or
one of its Vice Presidents or with the facsimile signature of its President, and
its corporate seal shall be thereunto affixed, or printed, lithographed, or
engraved thereon, in facsimile, and attested by the manual signature of its
Secretary or one of its Assistant Secretaries or with the facsimile signature of
its Secretary. In case any of the officers who shall have signed any bonds or
attested the seal thereon or whose facsimile signature shall be borne by the
bonds shall cease to be such officers of the Company before the bonds so signed
and sealed actually shall have been authenticated by the Trustee or delivered by
the Company, such bonds nevertheless may be issued, authenticated, and delivered
with the same force and effect as though the person or persons who signed such
bonds and attested the seal thereon or whose facsimile signature is borne by the
bonds had not ceased to be such officer or officers of the Company. Any bond
issuable hereunder may be signed or attested by manual or facsimile signature in
behalf of the Company by such person as at the actual date of the execution of
such bond shall be the proper officer of the Company, although at the date of
such bond such person shall not have been an officer of the Company.

         SECTION 2.06.     [(a) Except as provided in subsections (c) and (g)
below, the registered holder of all of the bonds of the Series due [_______]
shall be The Depository Trust Company ("DTC") and the bonds of the Series due
[_______] shall be registered in the name of Cede & Co., as nominee for DTC.
Payment of principal of[, premium, if any,] and interest on any bonds of the
Series due [_______] registered in the name of Cede & Co. shall be made by

                                      -13-

<PAGE>

transfer of New York Federal or equivalent immediately available funds with
respect to the bonds of the Series due [_______] to the account of Cede & Co. on
each such payment date for the bonds of the Series due [_______] at the address
indicated for Cede & Co. in the bond register kept by the Trustee.

         (b)      The bonds of the Series due [_______] shall be initially
issued in the form of one or more separate single authenticated fully registered
certificates in the aggregate principal amount of all bonds of the Series due
[_______]. Upon initial issuance, the ownership of such bonds of the Series due
shall be registered in the bond register kept by the Trustee in the name of Cede
& Co., as nominee of DTC. The Trustee and the Company may treat DTC (or its
nominee) as the sole and exclusive registered holder of the bonds of the Series
due [_______] registered in its name for the purposes of payment of the
principal of[, premium, if any,] and interest on the bonds of the Series due
[_______] and of giving any notice permitted or required to be given to holders
under the Indenture, except as provided in Section 2.06(g) below; and neither
the Trustee nor the Company shall be affected by any notice to the contrary.
Neither the Trustee nor the Company shall have any responsibility or obligation
to any of DTC's participants (each a "Participant"), any person claiming a
beneficial ownership in the bonds of the Series due [_______] under or through
DTC or any Participant (each a "Beneficial Owner"), or any other person which is
not shown on the bond register maintained by the Trustee as being a registered
holder, with respect to the accuracy of any records maintained by DTC or any
Participant; the payment to DTC or any Participant of any amount in respect of
the principal of[, premium, if any,] or interest on the bonds of the Series due
[_______]; any notice which is permitted or required to be given to registered
holders under the Indenture of bonds of the Series due [_______]; or any consent
given or other action taken by DTC as bondholder. The Trustee shall pay all
principal of[, premium, if any,] and interest on the bonds of the Series due
[_______] registered in the name of Cede & Co. only to or "upon the order of"
(as that term is used in the Uniform Commercial Code as adopted in Minnesota and
New York) DTC, and all such payments shall be valid and effective to fully
satisfy and discharge the Company's obligations with respect to the principal
of[, premium, if any,] and interest on such bonds of the Series due [_______] to
the extent of the sum or sums so paid. Except as otherwise provided in Sections
2.06(c) and (g) below, no person other than DTC shall receive authenticated bond
certificates evidencing the obligation of the Company to make payments of
principal of and interest on the bonds of the Series due [_______]. Upon
delivery by DTC to the Trustee of written notice to the effect that DTC has
determined to substitute a new nominee in place of Cede & Co., and subject to
the provisions of the Indenture with respect to transfers of bonds, the word
"Cede & Co." in this Supplemental Trust Indenture shall refer to such new
nominee of DTC.

         (c)      If the Company in its discretion determines that it is in the
best interest of the Beneficial Owners that they be able to obtain bond
certificates, the Company may notify DTC and the Trustee, whereupon DTC will
notify the Participants of the availability through DTC of bond certificates. In
such event, the Trustee shall issue, transfer and exchange bond certificates as
requested by DTC in appropriate amounts pursuant to Article II of the 1937
Indenture prior to the Effective Date, Article II of the Restated Indenture on
and after the Effective Date and Section 2.03 of this Supplemental Trust
Indenture. The Company shall pay all costs in connection with the production of
bond certificates if the Company makes such a determination under this Section
2.06(c). DTC may determine to discontinue providing its services with respect to
the bonds of the Series due [_______] at any time by giving written notice to
the Company

                                      -14-

<PAGE>

and the Trustee and discharging its responsibilities with respect thereto under
applicable law. Under such circumstances (if there is no successor book-entry
depository), the Company and the Trustee shall be obligated (at the sole cost
and expense of the Company) to deliver bond certificates as described in this
Supplemental Trust Indenture. If bond certificates are issued, the provisions of
the Indenture shall apply to, among other things, the transfer and exchange of
such certificates and the method of payment of principal of[, premium, if any,]
and interest on such certificates. Whenever DTC requests the Company and the
Trustee to do so, the Company will direct the Trustee (at the sole cost and
expense of the Company) to cooperate with DTC in taking appropriate action after
reasonable notice (1) to make available one or more separate certificates
evidencing the bonds of the Series due [_______] to any Participant or (2) to
arrange for another book-entry depository to maintain custody of certificates
evidencing the bonds of the Series due [_______] registered in the name of such
depository or its nominee. Any successor book-entry depository must be a
clearing agency registered with the Securities and Exchange Commission pursuant
to Section 17A of the Securities Exchange Act of 1934 and must enter into an
agreement with the Company and the Trustee agreeing to act as the depository and
clearing agency for the bonds of the Series due [_______] (except as provided in
Section 2.06(g) below). After such agreement has become effective, DTC shall
present the bonds of the Series due [_______] for registration of transfer in
accordance with Section 12 of Article II of the 1937 Indenture prior to the
Effective Date and Section 2.12 of the Restated Indenture on and after the
Effective Date, and the Trustee shall register them in the name of the successor
book-entry depository or its nominee. If a successor book-entry depository has
not accepted such position before the effective date of DTC's termination of its
services, the book-entry system shall automatically terminate and may not be
reinstated without the consent of all registered holders of the bonds of the
Series due [_______].

         (d)      Notwithstanding any other provision of this Supplemental Trust
Indenture to the contrary, so long as any bonds of the Series due [_______] are
registered in the name of Cede & Co., as nominee of DTC, all payments with
respect to the principal of[, premium, if any,] and interest on such Bonds of
the Series due [_______] and all notices with respect to such bonds of the
Series due [_______] shall be made and given, respectively, to DTC as provided
in the representation letter dated as of the date of delivery of the bonds of
the Series due [_______] among DTC, the Company and the Trustee. The Trustee is
hereby authorized and directed to comply with all terms of the representation
letter.

         (e)      In connection with any notice or other communication to be
provided pursuant to the Indenture for the bonds of the Series due [_______] by
the Company or the Trustee with respect to any consent or other action to be
taken by the registered holders of the bonds of the Series due [_______], the
Company or the Trustee, as the case may be, shall seek to establish a record
date to the extent permitted by the Indenture for such consent or other action
and give DTC notice of such record date not less than fifteen (15) calendar days
in advance of such record date to the extent possible. Such notice to DTC shall
be given only when DTC is the sole registered holder.

         (f)      NEITHER THE COMPANY NOR THE TRUSTEE WILL HAVE ANY
RESPONSIBILITY OR OBLIGATIONS TO THE PARTICIPANTS OR THE BENEFICIAL OWNERS WITH
RESPECT TO (1) THE ACCURACY OF ANY RECORDS MAINTAINED BY DTC OR ANY PARTICIPANT;
(2) THE PAYMENT BY DTC OR ANY PARTICIPANT OF ANY AMOUNT DUE TO ANY BENEFICIAL
OWNER IN RESPECT OF THE

                                      -15-

<PAGE>

PRINCIPAL OF[, PREMIUM, IF ANY,] OR INTEREST ON THE BONDS OF THE SERIES DUE
[_______]; (3) THE DELIVERY BY DTC OR ANY PARTICIPANT OF ANY NOTICE TO ANY
BENEFICIAL OWNER WHICH IS REQUIRED OR PERMITTED UNDER THE TERMS OF THE INDENTURE
TO BE GIVEN TO REGISTERED HOLDERS; (4) THE SELECTION OF THE BENEFICIAL OWNERS TO
RECEIVE PAYMENT IN THE EVENT OF ANY PARTIAL REDEMPTION OF THE BONDS OF THE
SERIES DUE [_______]; OR (5) ANY CONSENT GIVEN OR OTHER ACTION TAKEN BY DTC AS A
REGISTERED HOLDER.

         SO LONG AS CEDE & CO. IS THE REGISTERED HOLDER OF THE BONDS OF THE
SERIES DUE [_______] AS NOMINEE OF DTC, REFERENCES HEREIN TO REGISTERED HOLDERS
OF THE BONDS OF THE SERIES DUE [_______] SHALL MEAN CEDE & CO. AND SHALL NOT
MEAN THE BENEFICIAL OWNERS OF THE BONDS OF THE SERIES DUE [_______] NOR DTC
PARTICIPANTS.

         (g)      The Company, in its sole discretion, may terminate the
services of DTC with respect to the bonds of the Series due [_______] if the
Company determines that: (i) DTC is unable to discharge its responsibilities
with respect to the bonds of the Series due [_______]; or (ii) a continuation of
the requirement that all of the outstanding bonds of the Series due [_______] be
registered with the registration books kept by the Trustee in the name of Cede &
Co., as nominee of DTC, is not in the best interest of the Beneficial Owners of
the bonds of the Series due [_______]. After such event and if no substitute
book-entry depository is appointed by the Company, bond certificates will be
delivered as described in the Indenture.

         (h)      Upon the termination of the services of DTC with respect to
the bonds of the Series due [_______] pursuant to subsections (c) or (g) of this
Section 2.06 after which no substitute book-entry depository is appointed, the
bonds of the Series due [_______] shall be registered in whatever name or names
holders transferring or exchanging bonds of the Series due [_______] shall
designate in accordance with the provisions of the Indenture.]

                                   ARTICLE III
                                  [SINKING FUND

         SECTION 3.01.     (a) The Company covenants that it will on the first
day of October of each year commencing October 1, [_______], and continuing so
long as any of the bonds of the Series due [_______] are outstanding, pay or
cause to be paid to the Trustee, for and as a fund for the use and benefit of
the holders of bonds of the Series due [_______], a sum in lawful money of the
United States of America equal to the amount required to redeem on the first day
of December next following the date of such payment in accordance with Section
3.02, 1% of the highest aggregate principal amount of bonds of that series at
any time outstanding. Such fund shall be the Sinking Fund for bonds of the
Series due [_______]. [The Company covenants that it will meet its obligations
under the immediately preceding sentence for the year [_______] solely and
entirely through the application of permanent additions (or, if after the
Effective Date, through the application of an Amount of Established Permanent
Additions) in the manner hereinafter set forth in subdivision (c) of this
Section 3.01.]

                                      -16-

<PAGE>

         (b)      The delivery by the Company to the Trustee of bonds of the
Series due [_______] shall, for the purposes of satisfying the Sinking Fund for
bonds of that series, be deemed equivalent under this Section to the payment of
cash equal to the amount required to effect the redemption of the bonds so
delivered on the first day of December next following such delivery. If any
bonds of the Series due [_______] have been redeemed or retired and no bonds
have theretofore been issued, cash withdrawn, or credit taken under any of the
provisions of the Indenture on account of the redemption or retirement of such
bonds, the Company may deduct from any payment for the Sinking Fund for bonds of
the Series due [_______], an amount equivalent to the amount required to effect
the redemption of a like amount of bonds of that series for the Sinking Fund for
bonds of the Series due [_______], on the first day of December next following,
provided that the Company thereafter shall not issue any bonds, withdraw any
cash, or take any credit under any of the provisions of the Indenture on account
of the redemption or retirement of such bonds and such bonds shall be cancelled.
For the purpose of this subdivision (b), credit shall be deemed to have been
taken for any bonds redeemed or retired if used as a reduction of the amount of
cash required to be deposited with the Trustee under any provision of the
Indenture or out of funds pledged with the Trustee under any provision of the
Indenture, other than funds deposited with the Trustee for the payment of bonds
upon maturity or upon redemption at the option of the Company.

         (c)      Prior to the Effective Date, the delivery by the Company to
the Trustee of a written application of the Company, signed by its President or
a Vice President, to apply permanent additions acquired or constructed by the
Company (which, under the provisions of Article V of the 1937 Indenture, as
amended by the Supplemental Trust Indenture thereto dated February 1, 1944,
might otherwise be made the basis for the issuance of the bonds thereunder) to
the Sinking Fund provided for bonds of the Series due [_______] for the purpose
of such Sinking Fund shall be deemed equivalent under this Section to the
payment of cash equal to the amount required to effect the redemption on the
first day of December next following, of bonds of the Series due [_______], in
an amount equal to 66 2/3% of the cost or fair value, whichever is less, of the
permanent additions so applied, after making the deductions provided for in
Section 3 of Article V of the 1937 Indenture to a date not more than 90 days
preceding the date of the delivery to the Trustee of such application, on
account of property removed from service or abandoned and not replaced or
offset; provided that the Company thereafter shall not issue any bonds, withdraw
any cash, or take any credit under any of the provisions of the Indenture upon
the basis of the permanent additions so applied. Prior to the Effective Date,
such an application in each case shall be accompanied by the resolutions,
certificates, opinions, instruments, and other papers provided for in Subsection
(B) of Section 10 of Article XI of the 1937 Indenture, as amended by the
Supplemental Trust Indenture thereto dated February 1, 1944, in case of
withdrawal of cash from the Release Fund with such omissions or variations
therefrom or insertions therein as may be appropriate in the light of the
purpose for which they are used. On and after the Effective Date, the delivery
by the Company to the Trustee of a written application of the Company signed by
its President or a Vice President, to apply an Amount of Established Permanent
Additions established as provided in Sections 5.05 and 5.06 of the Indenture
(which has not been applied previously to any other purpose specified in the
Indenture) to the Sinking Fund provided for in this Article III, for purposes of
said Sinking Fund shall be deemed equivalent under this Section to the payment
of cash equal to the amount required to effect the redemption on the first day
of December next following, of a principal amount of Bonds of this Series equal
to 66 2/3% of the Amount of Established Permanent Additions so applied.

                                      -17-

<PAGE>

         SECTION 3.02.     (a). As soon as may be, after each payment to the
Sinking Fund provided for bonds of the Series due [_______] is so made, the
Trustee shall apply the moneys in such Sinking Fund to the purchase of bonds of
the Series due [_______], in the open market, at the lowest price or prices
obtainable, but not to exceed the price at which the bonds of such series are
then redeemable for the Sinking Fund as herein provided. If within 20 days after
each payment to the Sinking Fund, the Trustee shall be unable to purchase bonds
of the Series due [_______], as aforesaid, sufficient to reduce the amount of
money held in the Sinking Fund to less than $10,000, the Trustee shall apply the
Sinking Fund for bonds of the Series due [_______], or the balance thereof to
the redemption, on the first day of December next following the receipt of such
cash by the Trustee, of bonds of such series at the sinking fund redemption
prices provided for in Section 2.02 of this Supplemental Trust Indenture.

         (b)      The particular bonds to be redeemed for the Sinking Fund shall
be selected by the Trustee by lot, in such manner as it shall deem proper in its
discretion, from the distinctive numbers borne by or assigned to registered
bonds of the Series due [_______], as herein provided. For each registered bond
of a denomination in excess of $1,000, the Trustee shall assign a distinctive
number of each $1,000 of the principal amount thereof. Registered bonds shall be
deemed to have been drawn by lot if and to the extent that the numbers borne by
or assigned thereto as above provided are selected as aforesaid. The Trustee
shall notify the Company in writing of the distinctive numbers of the bonds of
the Series due [_______] to be redeemed for the Sinking Fund. The Trustee is
authorized and empowered hereby to give or cause to be given on behalf of the
Company the notice required by Section 2.02 hereof in order to redeem bonds for
Sinking Fund purposes.

         (c)      On and after the commencement of notice of redemption of bonds
pursuant to this Section, the Trustee shall (subject to the provisions of
Section 5 of Article XX of the 1937 Indenture prior to the Effective Date and to
the provisions of Section 20.03 of the Indenture on and after the Effective
Date) hold the moneys necessary to redeem the bonds so to be redeemed as a
separate trust fund for the account of the respective holders thereof and such
moneys shall be paid to them respectively upon presentation and surrender of
such bonds; and after the redemption date, such bonds shall cease to be entitled
to the lien, benefits, or security of the Indenture, and as respects the
Company's liability thereon such bonds and all claims for interest thereon shall
be deemed to have been paid; this Section being in all respects subject to the
provisions of Section 5 of Article XX of the 1937 Indenture prior to the
Effective Date and to the provisions of Section 20.03 of the Indenture on and
after the Effective Date, except that, on and after commencement of notice of
redemption of bonds pursuant to this Section 3.02, such bonds shall be deemed to
have been redeemed from the holder or holders thereof and paid for the purpose
of release and satisfaction of the Indenture.

         (d)      If there shall be drawn for redemption a portion of the
principal amount less than the entire amount of any registered bond, the Company
shall execute and the Trustee shall authenticate and deliver without charge to
the holder thereof registered bonds of the Series due [_______] for the
unredeemed balance of such registered bond.

         SECTION 3.03.     All bonds delivered to the Trustee in lieu of cash,
or purchased by the Trustee, or redeemed by operation of the Sinking Fund in
accordance with the provisions of this Article, shall be cancelled by the
Trustee. Bonds so cancelled shall not be reissued and no

                                      -18-

<PAGE>

additional bonds shall be authenticated and delivered in substitution therefor
or on account of the retirement thereof and no credit shall be taken or cash
withdrawn under the provisions of the Indenture on the basis thereof.]

                                   ARTICLE IV
                       APPOINTMENT OF AUTHENTICATING AGENT

         SECTION 4.01.     The Trustee shall, if requested in writing so to do
by the Company, promptly appoint an agent or agents of the Trustee who shall
have authority to authenticate registered bonds of Series due [_______] in the
name and on behalf of the Trustee. Such appointment by the Trustee shall be
evidenced by a certificate of a vice-president of the Trustee delivered to the
Company prior to the effectiveness of such appointment.

         SECTION 4.02.     (a) Any such authenticating agent shall be acceptable
to the Company and at all times shall be a corporation which is organized and
doing business under the laws of the United States or of any State, is
authorized under such laws to act as authenticating agent, has a combined
capital and surplus of at least $10,000,000 and is subject to supervision or
examination by Federal or State authority. If such corporation publishes reports
of condition at least annually, pursuant to law or to the requirements of the
aforesaid supervising or examining authority, then for the purposes of this
Section 4.02 the combined capital and surplus of such corporation shall be
deemed to be its combined capital and surplus as set forth in its most recent
report of condition so published.

         (b)      Any corporation into which any authenticating agent may be
merged or converted or with which it may be consolidated, or any corporation
resulting from any merger, conversion, or consolidation to which any
authenticating agent shall be a party, or any corporation succeeding to the
corporate agency business of any authenticating agent, shall continue to be the
authenticating agent without the execution or filing of any paper or any further
act on the part of the Trustee or the authenticating agent.

         (c)      Any authenticating agent at any time may resign by giving
written notice of resignation to the Trustee and to the Company. The Trustee may
at any time, and upon written request of the Company to the Trustee shall,
terminate the agency of any authenticating agent by giving written notice of
termination to such authenticating agent and to the Company. Upon receiving such
a notice of resignation or upon such a termination, or in case at any time any
authenticating agent shall cease to be eligible in accordance with the
provisions of this Section 4.02, the Trustee, unless otherwise requested in
writing by the Company, promptly shall appoint a successor authenticating agent,
which shall be acceptable to the Company. Any successor authenticating agent
upon acceptance of its appointment hereunder shall become vested with all the
rights, powers, duties, and responsibilities of its predecessor hereunder, with
like effect as if originally named. No successor authenticating agent shall be
appointed unless eligible under the provisions of this Section 4.02.

         (d)      The Trustee agrees to pay to any authenticating agent,
appointed in accordance with the provisions of this Section 4.02, reasonable
compensation for its services, and the Trustee shall be entitled to be
reimbursed for such payments.

                                      -19-

<PAGE>

         SECTION 4.03.     If an appointment is made pursuant to this Article
IV, the registered bonds of Series due [_______] shall have endorsed thereon,
in addition to the Trustee's Certificate, an alternate Trustee's Certificate in
the following form:

         This bond is one of the bonds of the Series designated thereon,
described in the within-mentioned Indenture.

                                         BNY MIDWEST TRUST
                                         COMPANY, as Trustee

                                         ___________________________________
                                         By:

                                         AUTHENTICATING AGENT

                                         ___________________________________
                                         By:
                                         AUTHORIZED OFFICER

         SECTION 4.04.     No provision of this Article IV shall require the
Trustee to have at any time more than one such authenticating agent for any one
State or to appoint any such authenticating agent in the State in which the
Trustee has its principal place of business.

                                   ARTICLE V
                       FINANCING STATEMENT TO COMPLY WITH
                           THE UNIFORM COMMERCIAL CODE

         SECTION 5.01.     The name and address of the debtor and secured party
are set forth below:

         Debtor:           Northern States Power Company
                           414 Nicollet Mall
                           Minneapolis, Minnesota 55401

         Secured Party:    BNY Midwest Trust Company, Trustee
                           2 North LaSalle Street
                           Suite 1020
                           Chicago, Illinois 60602

NOTE: Northern States Power Company, the debtor above named, is "a transmitting
utility" under the Uniform Commercial Code as adopted in Minnesota, North Dakota
and South Dakota.

                                      -20-

<PAGE>

         SECTION 5.02.     Reference to Article I hereof is made for a
description of the property of the debtor covered by this Financing Statement
with the same force and effect as if incorporated in this Section at length.

         SECTION 5.03.     The maturity dates and respective principal amounts
of obligations of the debtor secured and presently to be secured by the
Indenture and this Supplemental Trust Indenture, reference to all of which for
the terms and conditions thereof is hereby made with the same force and effect
as if incorporated herein at length, are as follows:

<TABLE>
<CAPTION>
                First Mortgage Bonds                                      Principal Amount
<S>                                                                       <C>
Series due December 1, 2005..........................................      $   70,000,000
Pollution Control Series J...........................................      $    5,450,000
Pollution Control Series K...........................................      $    3,400,000
Pollution Control Series L...........................................      $    4,850,000
Series due July 1, 2025..............................................      $  250,000,000
Pollution Control Series N...........................................      $   27,900,000
Pollution Control Series O...........................................      $   50,000,000
Pollution Control Series P...........................................      $   50,000,000
Series due March 1, 2028.............................................      $  150,000,000
Resource Recovery Series Q...........................................      $   15,170,000
Resource Recovery Series R...........................................      $   19,615,000
Series due August 15, 2003...........................................      $  308,000,000
Pollution Control Series S...........................................      $   69,000,000
Series A and Series B due August 28, 2012............................      $  450,000,000
Series due [______]..................................................      $      [______]
</TABLE>

         SECTION 5.04.     This Financing Statement is hereby adopted for all of
the First Mortgage Bonds of the Series mentioned above secured by said Indenture
and this Supplemental Trust Indenture.

         SECTION 5.05.     The 1937 Indenture and the prior Supplemental Trust
Indentures, as set forth below, have been filed or recorded in each and every
office in the States of Minnesota, North Dakota, and South Dakota designated by
law for the filing or recording thereof in respect of all property of the
Company subject thereto:

Original Indenture
    Dated February 1, 1937

Supplemental Indenture
    Dated June 1, 1942

Supplemental Indenture
    Dated February 1, 1944

                                      -21-

<PAGE>

Supplemental Indenture
    Dated October 1, 1945

Supplemental Indenture
    Dated July 1, 1948

Supplemental Indenture
    Dated August 1, 1949

Supplemental Indenture
    Dated June 1, 1952

Supplemental Indenture
    Dated October 1, 1954

Supplemental Indenture
    Dated September 1, 1956

Supplemental Indenture
    Dated August 1, 1957

Supplemental Indenture
    Dated July 1, 1958

Supplemental Indenture
    Dated December 1, 1960

Supplemental Indenture
    Dated August 1, 1961

Supplemental Indenture
    Dated June 1, 1962

Supplemental Indenture
    Dated September 1, 1963

Supplemental Indenture
    Dated August 1, 1966

Supplemental Indenture
    Dated June 1, 1967

Supplemental Indenture
    Dated October 1, 1967

                                      -22-

<PAGE>

Supplemental Indenture
    Dated May 1, 1968

Supplemental Indenture
    Dated October 1, 1969

Supplemental Indenture
    Dated February 1, 1971

Supplemental Indenture
    Dated May 1, 1971

Supplemental Indenture
    Dated February 1, 1972

Supplemental Indenture
    Dated January 1, 1973

Supplemental Indenture
    Dated January 1, 1974

Supplemental Indenture
    Dated September 1, 1974

Supplemental Indenture
    Dated April 1, 1975

Supplemental Indenture
    Dated May 1, 1975

Supplemental Indenture
    Dated March 1, 1976

Supplemental Indenture
    Dated June 1, 1981

Supplemental Indenture
    Dated December 1, 1981

Supplemental Indenture
    Dated May 1, 1983

Supplemental Indenture
    Dated December 1, 1983

                                      -23-

<PAGE>

Supplemental Indenture
    Dated September 1, 1984

Supplemental Indenture
    Dated December 1, 1984

Supplemental Indenture
    Dated May 1, 1985

Supplemental Indenture
    Dated September 1, 1985

Supplemental Indenture
    Dated May 1, 1988

Supplemental Indenture
    Dated July 1, 1989

Supplemental Indenture
    Dated June 1, 1990

Supplemental Indenture
    Dated October 1, 1992

Supplemental Indenture
    Dated April 1, 1993

Supplemental Indenture
    Dated December 1, 1993

Supplemental Indenture
    Dated February 1, 1994

Supplemental Indenture
    Dated October 1, 1994

Supplemental Indenture
    Dated June 1, 1995

Supplemental Indenture
    Dated April 1, 1997

Supplemental Indenture
    Dated March 1, 1998

                                      -24-

<PAGE>

Supplemental Indenture
    Dated May 1, 1999

Supplemental Indenture
    Dated June 1, 2000

Supplemental Indenture
    Dated August 1, 2000

Supplemental Indenture
    Dated June 1, 2002

Supplemental Indenture
    Dated July 1, 2002

Supplemental Indenture
    Dated August 1, 2002

         SECTION 5.06.     The property covered by this Financing Statement also
shall secure additional series of First Mortgage Bonds of the debtor which may
be issued from time to time in the future in accordance with the provisions of
the Indenture.

                                   ARTICLE VI
                             AMENDMENTS TO INDENTURE

         SECTION 6.01.     Each holder or registered owner of a bond of any
series originally authenticated by the Trustee and originally issued by the
Company subsequent to May 1, 1985 and of any coupon pertaining to any such bond,
by the acquisition, holding or ownership of such bond and coupon, thereby
consents and agrees to, and shall be bound by, the provisions of Article VI of
the Supplemental Trust Indenture dated May 1, 1985. Each holder or registered
owner of a bond of any series (including bonds of Series due [_______]),
originally authenticated by the Trustee and originally issued by the Company
subsequent to May 1, 1988 and of any coupon pertaining to such bond, by the
acquisition, holding or ownership of such bond and coupon, thereby consents and
agrees to, and shall be bound by, the provisions of the Supplemental and
Restated Trust Indenture dated May 1, 1988 upon the Effective Date.

                                   ARTICLE VII
                                  MISCELLANEOUS

         SECTION 7.01.     The recitals of fact herein, except the recital that
the Trustee has duly determined to execute this Supplemental Trust Indenture and
be bound, insofar as it may lawfully so do, by the provisions hereof and in the
bonds shall be taken as statements of the Company and shall not be construed as
made by the Trustee. The Trustee makes no representations as to the value of any
of the property subject to the lien of the Indenture, or any part thereof, or as
to the title of the Company thereto, or as to the security afforded thereby and
hereby, or as to the validity of this Supplemental Trust Indenture or of the
bonds issued under the

                                      -25-

<PAGE>

Indenture by virtue hereof (except the Trustee's certificate) and the Trustee
shall incur no responsibility in respect of such matters.

         SECTION 7.02.     This Supplemental Trust Indenture shall be construed
in connection with and as a part of the 1937 Indenture, as supplemented by the
Supplemental Trust Indentures dated June 1, 1942, February 1, 1944, October 1,
1945, July 1, 1948, August 1, 1949, June 1, 1952, October 1, 1954, September 1,
1956, August 1, 1957, July 1, 1958, December 1, 1960, August 1, 1961, June 1,
1962, September 1, 1963, August 1, 1966, June 1, 1967, October 1, 1967, May 1,
1968, October 1, 1969, February 1, 1971, May 1, 1971, February 1, 1972, January
1, 1973, January 1, 1974, September 1, 1974, April 1, 1975, May 1, 1975, March
1, 1976, June 1, 1981, December 1, 1981, May 1, 1983, December 1, 1983,
September 1, 1984, December 1, 1984, May 1, 1985, September 1, 1985, the
Supplemental and Restated Trust Indenture dated May 1, 1988 and the Supplemental
Trust Indentures dated July 1, 1989, June 1, 1990, October 1, 1992, April 1,
1993, December 1, 1993, February 1, 1994, October 1, 1994, June 1, 1995, April
1, 1997, March 1, 1998, May 1, 1999, June 1, 2000, August 1, 2000, June 1, 2002,
July 1, 2002 and August 1, 2002.

         Section 7.03.     (a) If any provision of this Supplemental Trust
Indenture limits, qualifies or conflicts with another provision of the Indenture
required to be included in indentures qualified under the Trust Indenture Act of
1939, as amended (as enacted prior to the date of this Supplemental Trust
Indenture) by any of the provisions of Sections 310 to 317, inclusive, of the
said Act, such required provision shall control.

         (b)      In case any one or more of the provisions contained in this
Supplemental Trust Indenture or in the bonds issued hereunder shall be invalid,
illegal, or unenforceable in any respect, the validity, legality and
enforceability of the remaining provisions contained herein and therein shall
not in any way be affected, impaired, prejudiced or disturbed thereby.

         SECTION 7.04.     Wherever in this Supplemental Trust Indenture the
word "Indenture" is used without either prefix, "1937", "Original" or
"Supplemental", such word was used intentionally to include in its meaning both
the 1937 Indenture and all indentures supplemental thereto.

         SECTION 7.05.     Wherever in this Supplemental Trust Indenture either
of the parties hereto is named or referred to, this shall be deemed to include
the successors or assigns of such party, and all the covenants and agreements in
this Supplemental Trust Indenture contained by or on behalf of the Company or by
or on behalf of the Trustee shall bind and inure to the benefit of the
respective successors and assigns of such parties, whether so expressed or not.

         SECTION 7.06.     (a) This Supplemental Trust Indenture may be
simultaneously executed in several counterparts, and all said counterparts
executed and delivered, each as an original, shall constitute but one and the
same instrument.

         (b)      The Table of Contents and the descriptive headings of the
several Articles of this Supplemental Trust Indenture were formulated, used and
inserted in this Supplemental Trust Indenture for convenience only and shall not
be deemed to affect the meaning or construction of any of the provisions hereof.

                                      -26-

<PAGE>

         The total aggregate amount of obligations to be issued forthwith under
this Supplemental Trust Indenture is $[_______].

                                      -27-

<PAGE>

         IN WITNESS WHEREOF, on this [_______] day of [_______], A.D. [_______],
NORTHERN STATES POWER COMPANY, a Minnesota corporation, party of the first part,
has caused its corporate name and seal to be hereunto affixed and this
Supplemental Trust Indenture effective [_______], [_______] to be signed by its
President or a Vice President, and attested by its Secretary or an Assistant
Secretary, for and in its behalf, and BNY MIDWEST TRUST COMPANY (as successor
trustee to Harris Trust and Savings Bank), an Illinois corporation, as Trustee,
party of the second part, to evidence its acceptance of the trust hereby
created, has caused its corporate name and seal to be hereunto affixed, and this
Supplemental Trust Indenture effective [_______], [_______], to be signed by its
President, a Vice President, or an Assistant Vice President, and attested by its
Secretary or an Assistant Secretary, for and in its behalf.

                                              NORTHERN STATES POWER COMPANY

                                              __________________________________
                                              By:
                                                 Its: Vice President

Attest:

___________________________
By:
  Its: Secretary

Executed by Northern States                                 (CORPORATE SEAL)
Power Company in the presence of:

___________________________
Witness

___________________________
Witness

                                      -28-

<PAGE>

                                              BNY MIDWEST TRUST COMPANY,
                                              as Trustee

                                              __________________________________
                                              By:
                                                 Its: Vice President

Attest:

___________________________
By:
   Its: Vice President

Executed by BNY Midwest Trust Company
in the presence of:

___________________________                                     (CORPORATE SEAL)
Witness

___________________________
Witness

                                      -29-

<PAGE>

STATE OF MINNESOTA)
                           ) ss.:
COUNTY OF HENNEPIN         )

         On this [_______] day of [_______] A.D. [_______], before me,
[_______], a Notary Public in and for said County in the State aforesaid,
personally appeared [_______] and [_______], to me personally known, and to me
known to be the [_______] and [_______], respectively, of Northern States Power
Company, one of the corporations described in and which executed the within and
foregoing instrument, and who, being by me severally duly sworn, each for
himself, did say that he, the said [_______] is a [_______], and [_______] is
the [_______], of said Northern States Power Company, a corporation; that the
seal affixed to the within and foregoing instrument is the corporate seal of
said corporation, and that said instrument was executed on behalf of said
corporation by authority of its stockholders and board of directors; and said
[_______] and [_______] each acknowledged said instrument to be the free act and
deed of said corporation and that such corporation executed the same.

         WITNESS my hand and notarial seal, this [_______] day of [_______],
A.D. [_______].

___________________________
[________]
Notary Public
My commission expires [_______]

                                                                   (NOTARY SEAL)

                                      -30-

<PAGE>

STATE OF MINNESOTA         )
                           ) ss.:
COUNTY OF HENNEPIN         )

         [_______] and [_______], being severally duly sworn, each deposes and
says that they are [_______] and [_______] respectively, of Northern States
Power Company, the corporation described in and which executed the within and
foregoing Supplemental Trust Indenture, as mortgagor; and each for himself
further says that said Supplemental Trust Indenture was executed in good faith,
and not for the purpose of hindering, delaying, or defrauding any creditor of
the said mortgagor.

___________________________                   __________________________________
[_______]                                     [_______]

         Subscribed and sworn to before me this [_______] day of [_______], A.D.
[_______].

___________________________
[_______]
Notary Public
My commission expires [_______]

                                                                   (NOTARY SEAL)

                                      -31-

<PAGE>

STATE OF ILLINOIS          )
                           ) ss.:
COUNTY OF COOK             )

         On this [_______] day of [_______] A.D. [_______], before me,
[_______], a Notary Public in and for said County in the State aforesaid,
personally appeared [_______] and [_______] to me personally known, and to me
known to be the [_______] and [_______], respectively, of BNY Midwest Trust
Company, one of the corporations described in and which executed the within and
foregoing instrument, and who, being by me severally duly sworn, each, did say
that he/she, the said [_______] is [_______], and he/she, the said [_______], is
the [_______], of said BNY Midwest Trust Company, a corporation; that the seal
affixed to the within and foregoing instrument is the corporate seal of said
corporation, and that said instrument was executed on behalf of said corporation
by authority of its board of directors; and said [_______] and [_______] each
acknowledged said instrument to be the free act and deed of said corporation and
that such corporation executed the same.

         WITNESS my hand and notarial seal, this [_______] day of [_______] A.D.
[_______].

___________________________
[_______]
Notary Public
My commission expires [_______]

                                                                   (NOTARY SEAL)

                                      -32-

<PAGE>

STATE OF ILLINOIS          )
                           ) ss.:
COUNTY OF COOK             )

         [_______] and [_______], being severally duly sworn, each for
himself/herself deposes and says that he/she, the said [_______], is [_______],
and he/she, the said [_______], is [_______], of BNY Midwest Trust Company, the
corporation described in and which executed the within and foregoing
Supplemental Trust Indenture, as mortgagee; and each for himself further says
that said Supplemental Trust Indenture was executed in good faith, and not for
the purpose of hindering, delaying, or defrauding any creditor of the mortgagor.

___________________________                   __________________________________
[_______]                                     [_______]

         Subscribed and sworn to before me this [_______] day of [_______] A.D.
[_______].

___________________________
[_______]
Notary Public
My commission expires [_______]

                                                                   (NOTARY SEAL)

                                      -33-

<PAGE>

                                   SCHEDULE A

         The property referred to in Article II of the foregoing Supplemental
Trust Indenture from Northern States Power Company to BNY Midwest Trust Company,
Trustee, effective as of [_______], [_______], includes the following property
hereafter more specifically described. Such description, however, is not
intended to limit or impair the scope or intention of the general description
contained in the granting clauses or elsewhere in the Original Indenture.

                     I. PROPERTIES IN THE STATE OF MINNESOTA

                                      -34-