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                             GREAT FALLS GAS COMPANY
                           INCENTIVE STOCK OPTION PLAN


THIS AGREEMENT, made in Great Falls, Montana on this 6th day of November, 
1992, between Great Falls Gas Company (hereinafter referred to as "Company") 
and hereinafter referred to as "Optionee"), an employee of the Company or a 
subsidiary thereof.

WHEREAS, the Company desires to maintain and develop personnel capable of
assuring the future success of the Company, to offer such personnel additional
incentives to put forth maximum efforts for the success of the business, and to
afford them an opportunity to acquire a proprietary interest in the Company
through stock options:

NOW, THEREFORE, in consideration of the mutual agreements stated hereinafter, 
the Company and Optionee agree that:

1.   STOCK OPTION. The Company hereby grants to the Optionee and the Optionee
     accepts an incentive option to purchase 2200 shares of the Company's stock
     at any time prior to November 6, 1997 at a purchase price of $14.25 per
     share, all subject to the terms, provisions and conditions of this 
     Agreement and of the Company's 1984 Stock Option Plan (hereinafter referred
     to as the "Plan"), which is incorporated herein by reference. Should there
     be any inconsistency between the provisions of this Agreement and the Plan,
     the provisions of the Plan shall control. This option may be exercised in 
     the following manner. In the first twelve months from the date of this
     agreement no more than twenty percent (440) of the options granted herein
     may be exercised; in the next succeeding twelve months no more than forty
     percent (880) of said options shall be exercisable, in the next succeeding
     twelve months no more than sixty percent (1320) of said options shall be
     exercisable; in the next succeeding twelve months no more than eighty
     percent (1760) of the options shall be exercisable. Other than the
     foregoing restriction this Agreement shall be exercised in the manner
     provided in the Plan as to all or any part of the shares of stock subject
     to the option from time to time during the option period, and exercise of
     the option as to part of such shares shall not exhaust or terminate the
     option. The option shall be exercised as to not less than One Hundred (100)
     shares at any one time, however. Payment of the option price shall be made
     concurrently with the exercise of the option as provided in the Plan.

2.   LIMITATION ON AMOUNT. In any calendar year, the aggregate fair market value
     (such value being determined as of the time the option is granted) of stock
     for which Optionee may be granted Incentive Stock Options shall not exceed
     One Hundred Thousand Dollars (100,000) plus any unused limit carryover to
     such year. (Any unused limit carryover amount shall be

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     determined as prescribed by Section 422A(c)(4) of the Internal Revenue Code
     of 1954, or similar provisions in succeeding enactments, and the
     regulations and rulings promulgated thereunder). In determining the maximum
     permissible value of Incentive Stock Options which may be granted to
     Optionee in any calendar year, all Incentive Stock Options granted under
     Incentive Stock Option Plans of the Company and its divisions or subsidiary
     corporations shall be considered in the aggregate. This annual $100,000
     limitation shall not apply to any stock option which is not an Incentive
     Stock Option as defined by Section 433A of the Internal Revenue Code of
     1954 (or similar provisions in succeeding enactments).

3.   EXERCISE OF OPTION. All Incentive Stock Options must be exercised
     sequentially; i.e., no Incentive Stock Option may be exercised by any one
     individual while there is outstanding any Incentive Stock Option to that
     same individual which was granted prior to the grant date of the Incentive
     Stock Option sought to be exercised. Any outstanding Incentive Stock Option
     shall be treated as outstanding until such option is exercised in full or
     expires by reason of lapse of time.

4.   PERCENT SHAREHOLDER RULE. Notwithstanding any other provision in the Plan,
     if at the time an option is otherwise to be granted pursuant to the Plan
     the Optionee owns directly or indirectly (within the meaning of Section
     425(d) of the Code), common stock of the Company possessing more than ten
     percent (10%) of the total combined voting power of all classes of stock of
     the Company or its parent or subsidiary corporations, if any (within the
     meaning of Section 422A(c)(8) of the Code, and the option price shall be
     not less than 110% of the fair market value of the common stock of the
     Company determined as described herein, and such option by its terms shall
     not be exercisable after the expiration of five (5) years from the date
     such option is granted.

5.   NON-TRANSFERABILITY AND TERMINATION OF EMPLOYMENT. No option granted under
     the Plan shall be transferable by an Optionee, otherwise than by will or
     the laws of descent of distribution as provided in Section 9(c) of the 
     Plan. During the lifetime of an Optionee, the option shall be exercisable 
     only by such Optionee. In the event that Optionee ceases to be employed 
     by the Company or its subsidiaries, if any, for any reason other than his 
     gross and willful misconduct or his death or disability, such Optionee 
     shall have the right to exercise the option at any time within three (3) 
     months after such termination of employment to the extent of the full 
     number of shares he was entitled to purchase under the option on the date 
     of termination, subject to the condition that no option shall be 
     exercisable after the expiration of the term of the option.

6.   DILUTION OR OTHER ADJUSTMENTS. If there shall be any change in the common
     stock through merger, consolidation, reorganization, recapitalization, 
     stock dividend (of whatever amount), stock split or other

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     change in the corporate structure, appropriate adjustments in the Plan and
     outstanding options shall be made by the Committee. In the event of any
     such changes adjustments shall include, where appropriate, changes in the
     aggregate number of shares subject to the Plan and the number of shares and
     the price per share subject to outstanding options.

7.   RIGHTS OF OPTIONEE NOT THAT OF SHAREHOLDER. The Optionee shall have no
     rights as a shareholder in respect of shares as to which this option shall
     not have been exercised and payment made as provided in the Plan, and the
     Optionee shall not be considered or treated as a record owner of shares
     with respect to which this option is exercised until the date that the
     stock certificate or certificates are actually issued and such issuance
     reflected on the stock records of the Company.

8.   SUCCESSORS AND ASSIGNS. This Agreement shall inure to the benefit of and be
     binding upon the heirs, legatees, legal representatives, successors and
     assigns of the parties hereto.

IN WITNESS WHEREOF, the Company has caused this Agreement to be duly executed by
its Compensation Committee thereunto duly authorized, and the Optionee has
signed the same, in duplicate originals, on the date and year first above
written.

                             GREAT FALLS GAS COMPANY




/s/ Ian B. Davidson                          /s/ Thomas N. McGowen, Jr.
------------------------------               --------------------------
Ian B. Davidson                              Thomas N. McGowen, Jr.



                                             /s/ Timothy J. Moylan
                                             --------------------------
                                             Timothy Moylan



                                             /s/ John P. Allen
                                             --------------------------
                                             Optionee