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                                                                   EXHIBIT 10.22
                                        


                          MORRISON KNUDSEN CORPORATION
                     AMENDED AND RESTATED STOCK OPTION PLAN

                      NONQUALIFIED STOCK OPTION AGREEMENT



     THIS AGREEMENT (this "Agreement"), dated as of January 14, 1998, is made by
and between Morrison Knudsen Corporation, a Delaware corporation hereinafter
referred to as "Company," and ROBERT A. TINSTMAN, an employee of the Company or
Subsidiary of the Company, hereinafter referred to as "Optionee":

     WHEREAS, the Company wishes to afford the Optionee the opportunity to
purchase shares of its $.01 par value Common Stock; and


     WHEREAS, the Company wishes to carry out the Plan (as hereinafter defined),
the terms of which are hereby incorporated herein by reference and made a part
hereof; and

     WHEREAS, the execution of a Nonqualified Stock Option Agreement in the form
hereof has been duly authorized by a resolution of the Board of Directors of the
Company duly adopted on January 14, 1998, and incorporated herein by reference;
and

     WHEREAS, this Option is intended to be a nonqualified stock option and
shall not be treated as an "incentive stock option" within the meaning of that
term under Section 422 of the Code;

     NOW, THEREFORE, in consideration of the mutual covenants herein contained
and other good and valuable consideration, receipt of which is hereby
acknowledged, the parties hereto do hereby agree as follows:


                                   ARTICLE I
                                        
                                  DEFINITIONS
                                        
     Wherever the following terms are used in this Agreement with initial
capital letters, they shall have the meanings specified in the Plan unless the
context clearly indicates otherwise.

Section 1.1 - Beneficiary
Section 1.2 - Code
Section 1.3 - Common Stock
Section 1.4 - Company
Section 1.5 - Employee
Section 1.6 - Exchange Act
Section 1.7 - Fair Market Value
Section 1.8 - Subsidiary
Section 1.9 - Termination of Employment

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     Wherever the following terms are used in this Agreement with initial
capital letters, they shall have the meanings specified below unless the context
clearly indicates otherwise.  The masculine pronoun shall include the feminine
and neuter, and the singular the plural, where the context so indicates.


Section 1.10 - Board
------------   -----

     "Board" shall mean the Board of Directors of the Company and shall include
any committee to which the Board of Directors may have delegated its authority
pursuant to Section 8.1 of the Plan.


Section 1.11 - Optionee
------------   --------

     "Optionee" shall mean the Employee named above to whom an Option is awarded
under this Agreement and the Plan.


Section 1.12 - Plan
------------   ----

     "Plan" shall mean the Morrison Knudsen Corporation Amended and Restated
Stock Option Plan, as amended and restated as of January 10, 1997, and as the
same may be further amended or restated.


Section 1.14 - Secretary
------------   ---------

     "Secretary" shall mean the Secretary of the Company.


Section 1.15 - Securities Act
------------   --------------

     "Securities Act" shall mean the Securities Act of 1933, as amended.



                                   ARTICLE II

                                AWARD OF OPTION

Section 2.1 - Grant of Award
-----------   --------------

     In consideration of the Optionee's execution of this Agreement and for
other good and valuable consideration, on the date hereof the Company
irrevocably awards to the Optionee the option to purchase any part or all of an
aggregate of 100,000 shares of its $.01 par value Common Stock upon the terms
and subject to the conditions set forth in the Plan and in this Agreement.

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Section 2.2 - Purchase Price
-----------   --------------

     The purchase price of the shares of stock covered by the Option shall be
$9.3750 per share without commission or other charge.


Section 2.3 - Consideration to Company
-----------   ------------------------

     In consideration of the awarding of this Option by the Company, the
Optionee agrees to render faithful and efficient services to the Company or a
Subsidiary, with such duties and responsibilities as the Company shall from time
to time prescribe, for a period of at least one (1) year from the date this
Option is awarded.  Nothing in this Agreement or in the Plan shall confer upon
the Optionee any right to continue in the employ of the Company or any
Subsidiary, or shall interfere with or restrict in any way the rights of the
Company and its Subsidiaries, which are hereby expressly reserved, to discharge
the Optionee at any time for any reason whatsoever, with or without cause.


Section 2.4 - Adjustments in Option
-----------   ---------------------

     The Board may make or provide for such adjustments in the (a) number of
shares of Common Stock covered by outstanding Options awarded hereunder, (b)
prices per share applicable to such Options, and (c) kind of shares (including
shares of another issuer) covered thereby, as the Board in its sole discretion
may in good faith determine to be equitably required in order to prevent
dilution or enlargement of the rights of Optionees, that otherwise would result
from (x) any stock dividend, stock split,  combination of shares,
recapitalization or other change in the capital structure of the Company, (y)
any merger, consolidation, spin-off, split-off, split-up, reorganization,
partial or complete liquidation or other distribution of assets, issuance of
rights or warrants to purchase securities or (z) any other corporate transaction
or event having an effect similar to any of the foregoing.  In the event of any
such transaction or event, the Board may provide in substitution for any or all
outstanding awards under this Agreement such alternative consideration as it may
in good faith determine to be equitable under the circumstances and may require
in connection therewith the surrender of all awards so replaced.



                                  ARTICLE III

                            PERIOD OF EXERCISABILITY
                                        
Section 3.1 - Commencement of Exercisability
-----------   ------------------------------

(a)  This Option shall become exercisable in four (4) cumulative installments as
     follows:

     (i)  The first installment shall consist of one-fourth (1/4) of the shares
          covered by the Option and shall become exercisable on the date that is
          one year from the date the Option was awarded.

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     (ii)   The second installment shall consist of one-fourth (1/4) of the
            shares covered by the Option and shall become exercisable on the
            date that is two years from the date the Option was awarded.

     (iii)  The third installment shall consist of one-fourth (1/4) of the
            shares covered by the Option and shall become exercisable on the
            date that is three years from the date the Option was awarded.

     (iv)   The fourth installment shall consist of one-fourth (1/4) of the
            shares covered by the Option and shall become exercisable on the
            date that is four years from the date the Option was awarded.

(b)  No portion of the Option which is unexercisable at Termination of
     Employment shall thereafter become exercisable.


Section 3.2 - Duration of Exercisability
-----------   --------------------------

     The installments provided for in Section 3.1 are cumulative.  Each such
installment which becomes exercisable pursuant to Section 3.1 shall remain
exercisable until it becomes unexercisable under Section 3.3.


Section 3.3 - Expiration of Option
-----------   --------------------

(a)  The Option may not be exercised to any extent by anyone after the first to
     occur of the following events:

     (i)    The expiration of ten (10) years from the date the Option was
            awarded; or

     (ii)   Except as set forth in 3.3(a) (iii) and (iv), the expiration of
            three (3) months after the Optionee's Termination of Employment; or

     (iii)  The expiration of twelve (12) months from the date of the Optionee's
            Termination of Employment by reason of permanent and total
            disability (within the meaning of Section 22(e) (3) of the Code) or
            by reason of retirement at or after age 65; or

     (iv)   If the Optionee dies while the Option is exercisable, the expiration
            of twelve (12) months from the date of the Optionee's death.


(b)  This Agreement shall amend that certain Employment Agreement dated as of
     January 1, 1993 between the Optionee and the Company (the "Employment
     Agreement"), in that, notwithstanding Article 4 of the Employment
     Agreement, no portion of this Option that is unvested as of the date the
     Optionee's employment with the Company is terminated for any reason shall
     be exercisable.

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                                   ARTICLE IV

                               EXERCISE OF OPTION
                                        

Section 4.1 - Person Eligible to Exercise
-----------   ---------------------------

     During the lifetime of the Optionee, only he or his guardian or legal
representative may exercise the Option or any portion thereof.  After the death
of the Optionee, any exercisable portion of the Option may, prior to the time
when the Option becomes unexercisable under Section 3.3, be exercised by his
personal representative or by any person empowered to do so under the Optionee's
will or under the then applicable laws of descent and distribution.


Section 4.2 - Partial Exercise
-----------   ----------------

     Any exercisable portion of the Option or the entire Option, if then wholly
exercisable, may be exercised in whole or in part at any time prior to the time
when the Option or portion thereof becomes unexercisable under Section 3.3;
provided, however, that each partial exercise shall be for not less than one
hundred (100) shares and shall be for whole shares only.


Section 4.3 - Manner of Exercise
-----------   ------------------

     The Option or any exercisable portion thereof, may be exercised solely by
delivery to the Secretary or his office of all of the following prior to the
time when the Option or such portion becomes unexercisable under Section 3.3:

(a)  Notice in writing signed by the Optionee or the other person then entitled
     to exercise the Option or portion, stating that the Option or portion is
     thereby exercised, such notice complying with all applicable rules
     established by the Board; and

(b)  Full payment for the shares with respect to which such option or portion is
     exercised, which payment shall be (i) in cash, (ii) through the delivery of
     shares of Common Stock owned by the Optionee for at least six months, duly
     endorsed for transfer to the Company with a Fair Market Value on the date
     of delivery equal to the aggregate exercise price of the Option or
     exercised portion thereof, or (iii) subject to the timing requirements of
     Section 5.3 of the Plan, through any combination of the consideration
     provided in the foregoing subparagraphs (i) or (ii); and

(c)  Such representations and documents as the Board deems necessary or
     advisable to effect compliance with all applicable provisions of the
     Securities Act of 1933, as amended, and any other federal or state
     securities laws or regulations.  The Board may also take whatever
     additional actions it deems appropriate to effect such compliance including
     (without limitation) placing legends on share certificates and issuing
     stop-transfer notices to agents and registrars;

(d)  Full payment to the Company (or other employer corporation) of all amounts
     which 

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     under federal, state or local tax law, it is required to withhold upon
     exercise of the Option; provided, however, the Company may permit the
                             -----------------
     Optionee, upon delivery of a written election to the Secretary of the
     Company (or to such other person who may be designated by the Board) to
     elect to have the Company withhold shares of Common Stock otherwise
     issuable upon the exercise of the Option. Shares of Common Stock so
     withheld will be credited against this tax obligation at their Fair Market
     Value; and

(e)  In the event the Option or portion shall be exercised pursuant to Section
     4.1 by any person or persons other than the Optionee, appropriate proof of
     the right of such person or persons to exercise the Option.


Section 4.4 - Conditions to Issuance of Stock Certificates
-----------   --------------------------------------------

     The shares of stock deliverable upon the exercise of the Option, or any
portion thereof, may be either previously authorized but unissued shares or
issued shares which have then been repurchased by the Company.  Such shares
shall be fully paid and non-assessable.  The Company shall not be required to
issue or deliver any certificate or certificates for shares of stock purchased
upon the exercise of the Option or portion thereof prior to fulfillment of all
of the following conditions:

(a)  The admission of such shares to listing on all stock exchanges on which
     such class of stock is then listed; and

(b)  The completion of any registration or other qualification of such shares
     under any state or federal law or under rulings or regulations of the
     Securities and Exchange Commission or of any other governmental regulatory
     body, which the Board shall deem necessary or advisable; and

(c)  The obtaining of any approval or other clearance from any state or federal
     governmental agency which the Board shall determine to be necessary or
     advisable; and

(d)  The payment to the Company (or other employer corporation) of all amounts
     which, under federal, state or local tax law, it is required to withhold
     upon exercise of the Option; and

(e)  The lapse of such reasonable period of time following the exercise of the
     Option as the Board may from time to time establish for reasons of
     administrative convenience.


Section 4.5 - Rights as Shareholder
-----------   ---------------------

     The holder of the Option shall not be, nor have any of the rights or
privileges of, a shareholder of the Company in respect of any shares purchasable
upon the exercise of any part of 

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the Option unless and until certificates representing such shares shall have
been issued by the Company to such holder.


                                   ARTICLE V

                                OTHER PROVISIONS


Section 5.1 - Administration
-----------   --------------

     The Board shall have the power to interpret the Plan and this Agreement and
to adopt such rules for the administration, interpretation and application of
the Plan as are consistent therewith and to interpret, amend or revoke any such
rules.  All actions taken and all interpretations and determinations made by the
Board in good faith shall be final and binding upon the Optionee, the Company
and all other interested persons.  No member of the Board shall be personally
liable for any action, determination or interpretation made in good faith with
respect to the Plan or the Option.


Section 5.2 - Option Not Transferable
-----------   -----------------------

     Options under the Plan may not be sold, pledged, assigned or transferred in
any manner other than by will or the laws of descent and distribution; provided,
                                                                       ---------
however, an Optionee may designate a Beneficiary to exercise his Option or other
-------                                                                         
rights under the Plan after his death.  Neither the Option nor any interest or
right therein or part thereof shall be liable for the debts, contracts or
engagements of the Optionee or his successors in interest or shall be subject to
disposition by transfer, alienation, anticipation, pledge, encumbrance,
assignment or any other means whether such disposition be voluntary or
involuntary or by operation of law by judgment, levy, attachment, garnishment or
any other legal or equitable proceedings (including bankruptcy), and any
attempted disposition thereof shall be null and void and of no effect; provided,
                                                                       ---------
however, that this Section 5.2 shall not prevent transfers by will or by the
-------                                                                     
applicable laws of descent and distribution.  An Option shall be exercised
during the Optionee's lifetime only by the Optionee or his guardian or legal
representative.


Section 5.3 - Shares to Be Reserved
-----------   ---------------------

     The Company shall at all times during the term of the Option reserve and
keep available such number of shares of stock as will be sufficient to satisfy
the requirements of this Agreement.


Section 5.4 - Notices
-----------   -------

     Any notice to be given under the terms of this Agreement to the Company
shall be addressed to the Company in care of its Secretary, and any notice to be
given to the Optionee shall be addressed to him at the address given beneath his
signature hereto.  By a notice given pursuant to this Section 5.4, either party
may hereafter designate a different address for notices to be given to him.  Any
notice which is required to be given to the Optionee shall, if the Optionee is
then deceased, be given to the Optionee's personal representative if such
representative has 

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previously informed the Company of his status and address by written notice
under this Section 5.4. Any notice shall be deemed duly given when enclosed in a
properly sealed envelope or wrapper addressed as aforesaid, deposited (with
postage prepaid) in a post office or branch post office regularly maintained by
the United States Postal Service.


Section 5.5 - Titles
-----------   ------

     Titles are provided herein for convenience only and are not to serve as a
basis for interpretation or construction of this Agreement.


Section 5.6 - Construction
-----------   ------------

     This Agreement shall be administered, interpreted and enforced under the
internal substantive laws of the State of Delaware.


Section 5.7 - Conformity to Securities Laws
-----------   -----------------------------

     The Optionee acknowledges that the Plan is intended to conform to the
extent necessary with all applicable federal and state laws, rules and
regulations, including provisions of the Securities Act and the Exchange Act and
any and all regulations and rules promulgated by the Securities and Exchange
Commission thereunder, including without limitation Rule 16b-3 under the
Exchange Act.  Notwithstanding anything herein to the contrary, the Plan shall
be administered, and the Option is awarded and may be exercised, only in such a
manner as to conform to such laws, rules and regulations.  To the extent
permitted by applicable law, the Plan and this Agreement shall be deemed amended
to the extent necessary to conform to such laws, rules and regulations.

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     IN WITNESS WHEREOF, this Agreement has been executed and delivered by the
parties hereto.



                              MORRISON KNUDSEN CORPORATION

                              By:   /s/ Stephen G. Hanks
                                 -----------------------------
                                    Stephen G. Hanks
                                    Executive Vice President


                              OPTIONEE


                              /s/ Robert A. Tinstman
                              -------------------------------
                              Robert A. Tinstman



                                Spousal Consent
                                ---------------


     The undersigned has read and is familiar with the preceding Agreement and
the Plan and hereby consents and agrees to be bound by all the terms of the
Agreement and the Plan.  Without limiting the foregoing, the undersigned
specifically agrees that the Company may rely on any authorization, instruction
or election made under the Agreement by the Optionee alone and that all of his
or her right, title or interest, if any, in the shares of Common Stock purchased
by the Optionee under the Agreement, whether arising by operation of community
property law, by property settlement or otherwise, shall be subject to all of
such terms.



                                /s/ Shirley Tinstman
                                -----------------------------
                                Shirley Tinstman

                                Shirley Tinstman
                                -----------------------------
                                Printed Name



Exhibit A:  Copy of the Plan

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