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                                AMENDMENT NO. 1            EXHIBIT (10)(a)(2)
                                      TO
                            UNIT PURCHASE AGREEMENT

    This Amendment No.1 to the Unit Purchase Agreement (the "AMENDMENT") is
entered into as of June 21, 2001 by and among NorthWestern Corporation, a
Delaware corporation ("PURCHASER"), Touch America Holdings, Inc., a Delaware
corporation ("SELLER") and The Montana Power Company, a Montana corporation
("MPC"). This Amendment is entered into as a material part of the
consideration under, and pursuant to the terms of the Unit Purchase Agreement
(the "UPA") dated as of September 29, 2000 by and among Purchaser, Seller and
MPC. Capitalized terms not otherwise defined herein have the meanings set
forth in the UPA.

    WHEREAS, the parties hereto desire to amend the UPA as set forth below,
and otherwise to affirm in all respects the terms and conditions of the UPA;

    NOW, THEREFORE, in consideration of the foregoing premises and of the
mutual covenants and obligations hereinafter set forth, the parties hereto
agree as follows:

    FIRST. AMENDMENT TO SECTION 4.18. Section 4.18 is hereby replaced in its
entirety and shall read as follows:

    "4.18. POWER SUPPLY.

        (a) Seller and MPC agree to advise, consult and cooperate with Purchaser
    regarding steps to be taken to manage power supply risks, including
    (i) securing power to replace that currently supplied under the wholesale
    buyback agreement with PPL Montana LLC that expires on June 30, 2002, and
    (ii) supplying MPC's residual customer load in full in the event the PSC
    proceeding on default supplier rules is not resolved by June 30, 2002, or if
    MPC's default supplier role is extended beyond July 1, 2002. Seller and MPC
    agree to take reasonable and prudent steps to mitigate such risk, including
    contracting for additional power supply, and to consult and cooperate with
    Purchaser in the taking of such steps.

        (b) Prior to Closing, MPC shall transfer and assign to Seller, or to an
    Affiliate of Seller (other than the Company or any of the Subsidiaries), and
    such assignee shall expressly assume, the ASiMI Contract in accordance with
    the terms thereof and pursuant to all applicable Laws. As of the date of
    such assignment, all liabilities, obligations, risks and responsibilities of
    MPC with respect to the ASiMI Contract shall become liabilities,
    obligations, risks and responsibilities solely of Seller or an Affiliate of
    Seller. Neither Purchaser or MPC nor any of their officers, directors,
    stockholders, representatives, agents, successors or assigns (including the
    Company) shall have any obligation, liability, risk, or responsibility in
    relation to the ASiMI Contract, PROVIDED, HOWEVER, THAT to the extent
    required to accomplish delivery of power to ASiMI under the contract as
    assigned, MPC may enter into a transmission or distribution services
    agreement with Seller or Seller's Affiliates on the same terms and
    conditions as MPC's standard form transmission or distribution services
    agreement under its then applicable filed tariff, including payment of the
    standard charges therefor. Seller shall use commercially reasonable efforts
    to obtain the written release of MPC and its successors (including the
    Company) from all past and future liability under the ASiMI Contract. From
    and after the effective date of the First Amendment, neither Seller nor MPC
    shall have any obligation to consult with Purchaser regarding steps taken to
    mitigate risk relating to the ASiMI Contract. From and after the effective
    date of the First Amendment, other than this SECTION 4.18(B) and
    SECTION 6.11, none of the representations, warranties, covenants or
    agreements of Seller or MPC under the UPA shall apply to the ASiMI Contract
    or to any actions taken by Seller or MPC with respect to the ASiMI Contract.

    SECOND. NEW SECTION 6.11. New Section 6.11 is hereby added to the UPA to
read as follows:

        "6.11 TRANSFER OF THE ASIMI CONTRACT: Prior to Closing, (i) MPC shall
    have transferred and assigned the ASiMI Contract, in accordance with the
    terms thereof and pursuant to all applicable

                                       48

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    Laws, to Seller or to an Affiliate of Seller in accordance with
    Section 4.18(b), (ii) the ASiMI Contract shall have been assumed by Seller
    or such Affiliate as provided in Section 4.18(b), and (iii) Seller or
    Seller's Affiliate shall have made all required filings and obtained all
    required consents, in connection with the ASiMI Contract and the transfer
    thereof, in each instance to Purchaser's reasonable satisfaction. Seller
    shall have provided a certificate of an officer of Seller or Seller's
    Affiliate that the assignee is ready and capable of fulfilling the ASiMI
    Contract and has made all required filings and obtained all required
    consents incident thereto and the transfer thereof."

    THIRD. AMENDMENT TO SECTION 10.02(A). Section 10.02(a) is hereby replaced
in its entirety and shall read as follows:

        "Indemnification for Restructuring; Divestiture; Oil and Gas Sale; ASiMI
    Contract. (a) Seller agrees to indemnify Purchaser Indemnitees in respect of
    and hold each of them harmless from and against any Adverse Consequences
    suffered, incurred or sustained by any of them and resulting from, arising
    out of or relating to (i) the Restructuring and/or the Divestiture,
    (ii) any aspect of the business of Seller (other than the Company and the
    Subsidiaries), (iii) regulatory requirements with respect to the use of the
    proceeds of the Oil and Gas Sale, (iv) the ASiMI Contract or any failure of
    performance or breach thereof, including, without limitation, any Adverse
    Consequences related to risk of service, litigation, property damage,
    personal injury or tort claim or punitive or exemplary damage, regardless of
    whether a Third Party claim is involved or claim by ASiMI for service under
    the ASiMI Contract or applicable law. Solely with respect to the
    indemnification relating to the ASiMI Contract hereunder, notwithstanding
    anything to the contrary contained in this Agreement (including, without
    limitation, Sections 10.06 and 10.07), upon receipt of a notice from any
    Purchaser Indemnitee by Seller of any such indemnification claim, Seller
    agrees immediately to take whatever steps are necessary to assume the
    defense of the claim and hold the Purchaser harmless at Seller's sole cost
    and expense and immediately to reimburse any expenses incurred or to be
    incurred by any Purchaser Indemnitee as a result of such claim. Thereafter,
    Seller shall immediately advance any and all costs and expenses incurred by
    any Purchaser Indemnitee, including, without limitation, costs and expenses
    incurred by any Purchaser Indemnitee to defend any Third Party claim against
    it. Such advances or reimbursements, as the case may be, shall be made by
    Seller to a Purchaser Indemnitee, immediately upon submission by such
    Purchaser Indemnitee of a written request for advance or reimbursement,
    along with reasonable evidence of costs or expenses incurred. Seller's
    obligations under this Section 10.02 shall survive indefinitely. In the
    event that Seller enters into any agreement to merge, or to sell its assets
    or otherwise enters into any transaction the effect of which is that other
    party to such agreement or arrangement effectively becomes the successor to
    Seller, the successor shall expressly assume all the obligations and duties
    in relation to this Agreement.

    FOURTH. AMENDMENTS TO SECTION 12.01. Section 12.01 is hereby amended as
follows:

        (i) The following definition is hereby added to Section 12.01:

           "ASIMI CONTRACT" means the Agreement For Electric Service by and
       between MPC and Advanced Silicon Materials, Inc. ("ASIMI") dated
       March 21, 1996, as amended from time to time, and the Agreement between
       The Montana Power Trading & Marketing Company and ASiMI dated as of
       June 1, 1998, as amended from time to time, and any agreements entered
       into in connection therewith or related thereto."

        (ii) The definition of "Budget" in Section 12.01 is hereby replaced in
    its entirety with the following definition:

    "BUDGET" means with respect to the fiscal year 2000, the FY2000 operating
budget of MPC and the Subsidiaries attached as SECTION 12.01 OF THE
DISCLOSURE SCHEDULE attached to the UPA, and, with respect to the fiscal year
2001, the FY2001 operating and capital budget of MPC and the Subsidiaries
which is attached hereto as Exhibit A."

                                       49

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        (iii) The following definition is hereby added to Section 12.01:

           "FIRST AMENDMENT" means Amendment No. 1 to the UPA dated as of June
       21, 2001, by and among Purchaser, Seller and MPC."

    FIFTH. AMENDMENT TO ANNEX I. Annex I to the UPA, the unaudited balance
sheet of MPC and the Subsidiaries as of July 31, 2000, shall be modified to
the extent necessary so that it does not reflect any liabilities relating to
the ASiMI Contract (the "RESTATED BALANCE SHEET"). If the Restated Balance
Sheet is required, it will be attached hereto in the form of Exhibit B, which
shall replace and be in lieu of the Annex I currently attached to the UPA.

    SIXTH. MISCELLANEOUS. As of the date hereof, (a) Purchaser hereby
forebears and waives its rights under the UPA relating to any breach or
alleged breach by Seller or MPC of any provision of the UPA known to
Purchaser and existing on the date hereof and (b) MPC and Seller hereby
forebear and waive their rights under the UPA relating to any breach or
alleged breach by Purchaser of any provision of the UPA known to MPC or
Seller and existing on the date hereof. The foregoing is not intended to
waive either MPC, Seller's or Purchaser's rights to require satisfaction of
closing conditions as they relate to matters not addressed by this Amendment,
including the parties' rights under Sections 2.09(b), 6.01 and 7.01,
respectively, of the UPA.

    This Amendment shall become effective upon execution and delivery hereof.

    Except as set forth in this Amendment, the UPA shall remain in full force
and effect and is hereby ratified by Purchaser, Seller and MPC.

    This Amendment shall be governed by and construed in accordance with the
laws of the State of New York applicable to a Contract executed and performed
in such State.

    IN WITNESS WHEREOF, this Amendment has been duly executed and delivered
by the duly authorized officer of each party hereto as of the date first
above written.

<Table>
<S>                                                    <C>  <C>
                                                       NORTHWESTERN CORPORATION

                                                       By:  /s/ ERIC R. JACOBSEN
                                                            -----------------------------------------
                                                            Name: Eric R. Jacobsen
                                                            Title: Vice President, General Counsel
</Table>

<Table>
<S>                                                    <C>  <C>
                                                       TOUCH AMERICA HOLDINGS, INC.

                                                       By:  /s/ J.P. PEDERSON
                                                            -----------------------------------------
                                                            Name: J.P. Pederson
                                                            Title: Vice President & Chief Financial
                                                            Officer
</Table>

<Table>
<S>                                                    <C>  <C>
                                                       THE MONTANA POWER COMPANY

                                                       BY:  /S/ J.P. PEDERSON
                                                            -----------------------------------------
                                                            Name: J.P. Pederson
                                                            Title: Vice President & Chief Financial
                                                            Officer
</Table>

                                       50Prepared by MERRILL CORPORATION

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EXHIBIT 10.1    
  

 
 

CENTERPOINT PROPERTIES TRUST
  STOCK OPTION AGREEMENT    
  

    THIS STOCK OPTION AGREEMENT (the "Agreement") is dated as of May 16, 2001 between CenterPoint Properties Trust, a Maryland real estate investment trust
(the "Company"), and Nicholas C. Babson (the "Optionee"). 

    This
Agreement is made pursuant to, and is governed by, the CenterPoint Properties Trust 2000 Omnibus Employee Retention and Incentive Plan (the "2000
Plan"). Capitalized terms not otherwise defined herein shall have the meanings set forth in the Plan. The purpose of this Agreement is to establish a written agreement
evidencing an option granted in accordance with the terms of the Plan. In this Agreement, "shares" means shares of the Company's Common Stock or other securities resulting from an adjustment under
Article 8 of the Plan. 

    The
parties agree as follows: 

	1.
	Grant of Option.  The Company hereby grants to the Optionee an option (the "Option")
to purchase 5,000 shares under the terms and conditions hereof.

	2.
	Term.  The Option becomes exercisable and terminates in accordance with the schedule
set forth in Section 5 hereof; provided, however, that in the event employment of the Optionee with the Company or a Subsidiary terminates for any reason, the Option shall terminate in
accordance with the provisions of Section 7.2 of the Plan.

	3.
	Price.  The price of each share purchased by exercise of the Option is $46.51.

	4.
	Partial Exercise.  The Option, to the extent exercisable under Section 5
hereof, may be exercised in whole or in part provided that the Option may not be exercised for less than 100 shares in any single transaction unless such exercise pertains tot he entire number of
shares then covered by the Option.

	5.
	Exercise Period.
	(a)
	Except
as otherwise provided in the Plan or in this Agreement, the Option shall become exercisable as follows: 

	Time Period
	 	Exercisable

	Prior to the first anniversary of the date of this Agreement	 	None
	After the first anniversary of the date of this Agreement	 	One-fifth
	After the second anniversary of the date of this Agreement	 	Two-fifths
	After the third anniversary of the date of this Agreement	 	Three-fifths
	After the fourth anniversary of the date of this Agreement	 	Four-fifths
	After the fifth anniversary of the date of this Agreement	 	All

	(b)
	If
it has not previously terminated pursuant to the terms of the Plan or this Agreement, the Option shall terminate at the close of business on the day before the tenth anniversary
of the date of this Agreement. 

	6.
	Method of Exercise.  The Option shall be exercised by written notice by Optionee to
the Company specifying the number of shares that such person elects to purchase, accompanied by full payment, in cash or current funds, for such shares.

	7.
	ISO Treatment.  It is intended that the Option shall qualify as an "incentive stock
option" as described in Section 422 of the Internal Revenue Code of 1986, as amended.

	8.
	Rights of Stockholder.  No person, estate, or other entity will have the rights of a
stockholder with respect to shares subject to the Options until a certificate or certificates for these shares have been delivered to the person exercising the option. 

 
	9.
	Rights of the Company.  This Agreement does not affect the Company's right to take any
corporate action, including other changes in its right to recapitalize, reorganize or consolidate, issue bonds, notes or stock, including preferred stock or options therefor, to dissolve or liquidate,
or to sell or transfer any part of its assets or business.

	10.
	Changes in Capitalization.  Upon the occurrence of an event described in
Section 8.1(a) of the Plan, the Committee shall make the adjustments specified in Section 8.1(b) of the Plan.

	11.
	Taxes.  The company, if necessary or desirable, may pay or withhold the amount of any
tax attributable to any shares deliverable under this Agreement, and the company may defer making delivery until it is indemnified to its satisfaction for that tax.

	12.
	Compliance with Laws.  Options are exercisable, and shares can be delivered under this
Agreement, only in compliance with all applicable federal and state laws and regulations, including without limitation state and federal securities laws, and the rules of all stock exchanges on which
the Common Stock is listed at any time. Options may not be exercised and shares may not be issued under this Agreement until the Company has obtained the consent or approval of every regulatory body,
federal or state, having jurisdiction over such matters as the Committee deems advisable. Each person or estate that acquired the right to exercise an Option by bequest or inheritance may be required
by the Committee to furnish reasonable evidence of ownership of the Option as a condition to the exercise of the Option. In addition, the Committee may require such consents and releases of taxing
authorities as the Committee deems advisable.

	13.
	Stock Legends.  Any certificate issued to evidence shares issued under the Option
shall bear such legends and statements as the committee deems advisable to assure compliance with all federal and state laws and regulations.

	14.
	Assignability.  The Option shall not be transferable other than by will or the laws of
descent and distribution. G the Optionee's lifetime, the Option shall be exercisable only by the Optionee, except as otherwise provided herein. The Option shall be transferable, on the Optionee's
death, to the Optionee's estate and shall be exercisable, during the Optionee's lifetime, by the Optionee's guardian or legal representative.

	15.
	No Right of Employment.  Nothing in this Agreement shall confer any right on an
employee to continue in the employ of the Company or shall interfere in any way with the right of the Company to terminate such employee's employment at any time.

	16.
	Amendment of Option.  The Company may alter, amend, or terminate the Option only with
the Optionee's consent, except for adjustments expressly provided by this Agreement.

	17.
	Choice of Law.  The provisions of Section 9.6 of the Plan, concerning choice of
law, shall govern this Agreement.

	18.
	Miscellaneous.  This Agreement is subject to and controlled by the Plan. Any
inconsistency between this Agreement and said Plan shall be controlled by the Plan. This Agreement is the final, complete, and exclusive expression of the understanding between the parties and
supersedes any prior or contemporaneous agreement or representation, oral or written, between them. Modification of this Agreement or waiver of a condition herein must be written and signed by the
party to be bound. In the event that any paragraph or provision of this Agreement shall be held to be illegal or unenforceable, such paragraph or provision shall be severed from the Agreement and the
entire Agreement shall not fail on account thereof, but shall otherwise remain in full force and effect.

	19.
	Notices.  All notices and other communications required or permitted under this
Agreement shall be written, and shall be either delivered personally or sent by registered or certified first-class mail, postage prepaid and return receipt requested, or by telex or telecopier,
addressed as 

2

 

follows:
if to the Company, to the Company's principal office, and if to the Optionee or his successor, to the address last furnished by such person to the Company. Each such notice and communication
delivered personally shall be deemed to have been given when delivered. Each such notice and communication given by mail shall be deemed to have been given when it is deposited in the United States
mail in the manner specified herein, and each such notice and communication given by telex or telecopier shall be deemed to have been given when it is so transmitted and the appropriate answer back is
received. A party may change its address for the purpose hereof by giving notice in accordance with the provisions of this Section 19. 

    IN
WITNESS WHEREOF, the Optionee and the Company have executed this Agreement as of the date first written above. 

	

 	

CENTERPOINT PROPERTIES TRUST
	

 	

By:	
 	

 Rockford O. Kottka
	 	Its:	 	Executive Vice President and Treasurer
	

 	

GRANTEE
	

 	

 Printed Name: Nicholas C. Babson

3

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EXHIBIT 10.1

CENTERPOINT PROPERTIES TRUST STOCK OPTION AGREEMENT

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