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                               GREAT FALLS GAS COMPANY
                                1992 STOCK OPTION PLAN

1.  PURPOSE OF PLAN.

         This Plan shall be known as the "GREAT FALLS GAS COMPANY 1992 STOCK
OPTION PLAN" and is hereinafter referred to as the "Plan". The purpose of the
Plan is to aid in maintaining and developing personnel capable of assuring the
future success of Great Falls Gas Company, a Montana corporation (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. Options
granted under this Plan may be either incentive stock options ("Incentive Stock
Options") within the meaning of Section 422 of the Internal Revenue Code of 1986
(the "Code"), or options which do not qualify as Incentive Stock Options.

2.  STOCK SUBJECT TO PLAN.

         Subject to the provisions of Section 12 hereof, the stock to be
subject to options under the Plan shall be the Company's authorized Common
Shares, $.15 par value per share. Such shares may be either authorized but
unissued shares, or issued shares which have been reacquired by the Company.
Subject to adjustment as provided in Section 12 hereof, the maximum number of
shares on which options may be exercised issued under this Plan shall be 50,000
shares. If an option under the Plan expires, or for any reason is terminated or
unexercised with respect to any shares, such shares shall again be available for
options thereafter granted during the term of the Plan.

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3.  ADMINISTRATION OF PLAN.

         (a) The Plan shall be administered by a committee (the "Committee") of
two or more directors of the Company, none of whom shall be officers or
employees of the Company and all of whom shall be "disinterested persons" with
respect to the Plan within the meaning of Rule 16b-3 under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), or any successor rule or
regulation thereto.

         (b) The Committee shall have plenary authority in its discretion, but
subject to the express provisions of the Plan: (i) to determine the purchase
price of the Common Stock covered by each option, (ii) to determine the
employees to whom and the time or times at which such options shall be granted
and the number of shares to be subject to such options, (iii) to determine the
terms of exercise of each option, (iv) to accelerate the time at which all or
any part of an option may be exercised, (v) to amend or modify the terms of any
option with the consent of the optionee, (vi) to interpret the Plan, (vii) to
prescribe, amend and rescind rules and regulations relating to the Plan, (viii)
to determine the terms and provisions of each option agreement under the Plan
(which agreements need not be identical), including the designation of those
options intended to be Incentive Stock Options, and (ix) to make all other
determinations necessary or advisable for the administration of the Plan,
subject to the exclusive authority of the Board of Directors under Section 13
herein to amend or terminate the Plan. The


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Committee's determinations on the foregoing matters, unless otherwise
disapproved by the Board of Directors of the Company, shall be final and
conclusive.


         (c) The Committee shall select one of its members as its Chairman and
shall hold its meetings at such times and places as it may determine. A majority
of its members shall constitute a quorum. All determinations of the Committee
shall be made by not less than a majority of its members. Any decision or
determination reduced to writing and signed by all of the members of the
Committee shall be fully effective as if it had been made by a majority vote at
a meeting duly called and held. The grant of an option shall be effective only
if a written agreement shall have been duly executed and delivered by and on
behalf of the Company following such grant. The Committee may appoint a
Secretary and may make such rules and regulations for the conduct of its
business as it shall deem advisable.

4.  ELIGIBILITY.

         Incentive Stock Options may only be granted under this Plan to any
full or part-time employee (which term as used herein includes, but is not
limited to, officers and directors who are also employees) of the Company and of
its present and future subsidiary corporations within the meaning of Section
424(f) of the Code (herein called "subsidiaries"). Full or part-time employees,
directors who are not also employees, consultants or independent contractors to
the Company or one of its subsidiaries shall be eligible to receive options 
which do not qualify as Incentive Stock Options. In determining the persons to 
whom options shall be granted and the number of shares subject to such options, 
the Committee may take into account


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the nature of services rendered by the respective employees or consultants,
their present and potential contributions to the success of the Company and such
other factors as the Committee in its discretion shall deem relevant. A person
who has been granted an option under this Plan may be granted additional options
under the Plan if the Committee shall so determine; provided, however, that for
Incentive Stock Options granted after December 31, 1986, to the extent the
aggregate fair market value (determined at the time the Incentive Stock Option
is granted) of the Common Shares with respect to which all Incentive Stock
Options are exercisable for the first time by an employee during any calendar
year (under all plans described in subsection (d) of Section 422 of the Code of
his employer corporation and its parent and subsidiary corporations) exceeds
$100,000, such options shall be treated as options which do not qualify as
Incentive Stock Options. Nothing in the Plan or in any agreement thereunder
shall confer on any employee any right to continue in the employ of the Company
or any of its subsidiaries or affect, in any way, the right of the Company or
any of its subsidiaries to terminate his or her employment at any time.

5. PRICE.

         The option price for all Incentive Stock Options granted under the
Plan shall be determined by the Committee but shall not be less than 100% of the
fair market value of the Common Shares at the date of grant of such option. The
option price for options granted under the Plan which do not qualify as
Incentive Stock Options shall also be determined by the Committee but shall not
be less than 100%


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of the fair market value of the Common Shares at the date of grant of such
option. For purposes of the preceding two sentences and for all other valuation
purposes under the Plan, the fair market value of the Common Shares shall be (i)
the closing price of the Common Stock as reported for composite transactions if
the Common Stock is then traded on a national securities exchange, (ii) the last
sale price if the Common Stock is then quoted on the NASDAQ National Market
System, or (iii) the average of the closing representative bid and asked prices
of the Common Stock as reported on NASDAQ on the date as of which the fair
market value is being determined. If on the date of grant of any option
hereunder the Common Shares are not traded on an established securities market,
the Committee shall make a good faith attempt to satisfy the requirements of
this Section 5 and in connection therewith shall take such action as it deems
necessary or advisable.

6.  TERM.

         Each option and all rights and obligations thereunder shall expire on
the date determined by the Committee and specified in the option agreement. The
Committee shall be under no duty to provide terms of like duration for options
granted under the Plan, but the term of an Incentive Stock Option may not extend
more than ten (10) years from the date of grant of such option and the term of
options granted under the Plan which do not qualify as Incentive Stock Options
may not extend more than ten (10) years from the date of granting of such
option.


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7.  EXERCISE OF OPTION.

         (a) The Committee shall have full and complete authority to determine
whether an option will be exercisable in full at any time or from time to time
during the term thereof, or to provide for the exercise thereof in such
installments, upon the occurrence of such events (such as termination of
employment for any reason) and at such times during the term of the option as
the Committee may determine and specify in the option agreement.

         (b) The exercise of any option granted hereunder shall only be
effective at such time that the sale of Common Shares pursuant to such exercise
will not violate any state or federal securities or other laws. Only to the
extent required in order to comply with Rule 16b-3 under the Exchange Act, in
the case of an option or other award granted to a person considered by the
Company as one of its officers or directors for purposes of Section 16 of the
Exchange Act, the terms of the option or other award will require that such
shares are not disposed of by such officer or director for a period of at least
six months from the date of grant.

         (c) An optionee or grantee electing to exercise an option shall give
written notice to the Company of such election and of the number of shares
subject to such exercise. The full purchase price of such shares shall be
tendered with such notice of exercise. Payment shall be made to the Company in
cash (including bank check, certified check, personal check, or money order),
or, at the discretion of the Committee and as specified by the Committee, (i) by
delivering certificates for the Company's Common Shares already owned by the
optionee or grantee having a fair


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market value as of the date of grant equal to the full purchase price of the
shares, or (ii) by delivering the optionee's or grantee's promissory note, which
shall provide for interest at a rate not less than the minimum rate required to
avoid the imputation of income, original issue discount or a below-market-rate
loan pursuant to Sections 483, 1274 or 7872 of the Code or any successor
provisions thereto, or (iii) a combination of cash, the optionee's or grantee
promissory note and such shares. The fair market value of such tendered shares
shall be determined as provided in Section 5 herein. The optionee's or grantee's
promissory note shall be a full recourse liability of the optionee and may, at
the discretion of the Committee, be secured by a pledge of the shares being
purchased. Until such person has been issued the shares subject to such
exercise, he or she shall possess no rights as a shareholder with respect to
such shares.

8.  INCOME TAX WITHHOLDING AND TAX BONUSES.

         (a) In order to comply with all applicable federal or state income tax
laws or regulations, the Company may take such action as it deems appropriate to
ensure that all applicable federal or state payroll, withholding, income or
other taxes, which are the sole and absolute responsibility of an optionee or
grantee under the Plan, are withheld or collected from such optionee or grantee.
In order to assist an optionee or grantee in paying all federal and state taxes
to be withheld or collected upon exercise of an option which does not qualify as
an Incentive Stock Option hereunder, the Committee, in its absolute discretion
and subject to such additional terms and conditions as it may adopt, shall
permit the optionee or


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grantee to satisfy such tax obligation by (i) electing to have the Company
withhold a portion of the shares otherwise to be delivered upon exercise of such
option with a fair market value, determined in accordance with Section 5 herein,
equal to such taxes or (ii) delivering to the Company Common Shares other than
the shares issuable upon exercise of such option with a fair market value,
determined in accordance with Section 5, equal to such taxes.

         (b) The Committee shall have the authority, at the time of grant of an
option under the Plan or at any time thereafter, to approve tax bonuses to
designated optionees or grantees to be paid upon their exercise of options
granted hereunder. The amount of any such payments shall be determined by the
Committee. The Committee shall have full authority in its absolute discretion to
determine the amount of any such tax bonus and the terms and conditions
affecting the vesting and payment thereafter.

9.  ADDITIONAL RESTRICTIONS.

         The Committee shall have full and complete authority to determine
whether all or any part of the Common Shares of the Company acquired upon
exercise of any of the options granted under the Plan shall be subject to
restrictions on the transferability thereof or any other restrictions affecting
in any manner the optionee's or grantee's rights with respect thereto, but any
such restriction shall be contained in the agreement relating to such options.

10. TEN PERCENT SHAREHOLDER RULE.


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         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 424(d) of the Code) Common
Shares 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 422(b)(6) of the
Code), then any Incentive Stock Option to be granted to such optionee pursuant
to the Plan shall satisfy the requirements of Section 422(c)(5) of the Code, and
the option price shall be not less than 110% of the fair market value of the
Common Shares 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.

11. NON-TRANSFERABILITY.

         No option granted under the Plan shall be transferable by an optionee
or grantee, otherwise than by will or the laws of descent or distribution.
Except as otherwise provided in an option agreement, during the lifetime of an
optionee or grantee, the option shall be exercisable only by such optionee or
grantee.

12. DILUTION OR OTHER ADJUSTMENTS.

         If there shall be any change in the Common Shares through merger,
consolidation, reorganization, recapitalization, dividend in the form of stock
(of whatever amount), stock split or other 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


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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, in
order to prevent dilution or enlargement of option rights.

13. AMENDMENT OR DISCONTINUANCE OF PLAN.

         The Board of Directors may amend or discontinue the Plan at any time.
Subject to the provisions of Section 12 no amendment of the Plan, however, shall
without shareholder approval: (i) increase the maximum number of shares under
the Plan as provided in Section 2 herein, (ii) decrease the minimum price
provided in Section 5 herein, (iii) extend the maximum term under Section 6, or
(iv) modify the eligibility requirements for participation in the Plan. The
Board of Directors shall not alter or impair any option theretofore granted
under the Plan without the consent of the holder of the option.

14. TIME OF GRANTING.

         Nothing contained in the Plan or in any resolution adopted or to be
adopted by the Board of Directors or by the shareholders of the Company, and no
action taken by the Committee or the Board of Directors (other than the
execution and delivery of an option agreement), shall constitute the granting of
an option hereunder.

15. EFFECTIVE DATE AND TERMINATION OF PLAN.

         (a) The Plan was approved by the Board of Directors on September 1,
1992, and shall be approved by the shareholders of the Company within twelve
(12) months thereof.


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    (b) Unless the Plan shall have been discontinued as provided in Section 13
hereof, the Plan shall terminate September 1, 2002. No option may be granted
after such termination, but termination of the Plan shall not, without the
consent of the optionee or grantee, alter or impair any rights or obligations
under any option theretofore granted.


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