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                                                                   Exhibit 10.39

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                                     1997


                            MANAGEMENT INCENTIVE PLAN


                                 EFFECTIVE 1/1/97
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                                    PURPOSE


It is deemed desirable and in the best interests of the Stockholders and
Corporation that a portion of total compensation be made available to key
employees, in the form of incentive opportunity, when they discharge their
responsibilities in a manner which makes a measurable contribution to the
Corporation.

This is a general summary description of the Plan and is provided as an
information communication to Plan participants.  A detailed Plan document is
available through the Vice President, Human Resources and upon request, any
participant may review the full text.





                                 January, 1997

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MANAGEMENT INCENTIVE PLAN - JANUARY, 1997                                 PAGE 1
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CONCEPT

Participants are eligible to earn an annual incentive award based on attainment
of pre-approved Corporate, Area, Region, Division, or Safety goals. 
Participants are assigned a target incentive award stated as a percent of base
salary.  The target incentive award, or a greater or lesser amount as based on a
preset schedule, will be calculated at year-end based on the attainment of
predetermined goals.  The plan year shall be January 1, 1997 - December 31,
1997.


ELIGIBILITY

Eligibility for participation in the Plan will be limited to those key employees
who, by the nature and scope of their position, regularly and directly make or
influence policy or operating decisions which impact the profitability and
earnings results of the Company.  However, employees participating in a sales
incentive, or commission arrangement, or those covered by a consulting
agreement, shall be excluded from participation in this Plan.


PARTICIPATION

Participation in the Plan shall be determined annually and approved by the Board
of Directors.  The Board shall base its approval upon the recommendations of the
Compensation Committee of the Board of Directors.  Employees approved for
participation shall be notified of their selection as soon after approval as
practicable.


PARTIAL PLAN YEAR PARTICIPATION

The Board may allow an individual who becomes eligible during the Plan year to
participate in the Plan.  In such case, the participant's final award shall be
prorated based on the number of full months of participation during the
pertinent Plan year.

A participant whose incentive category level is changed during the Plan year
shall receive a bonus based on the number of months spent in each incentive
category during the Plan year.  The proration shall be determined by multiplying
the final award for a full year of participation at each incentive category
level by a fraction; the numerator of which shall be the number of months spent
at the incentive category level and the denominator of which shall be twelve
(12).  The participant's final award shall be the sum of the prorated awards
calculated for the time spent at each incentive category level, with
consideration to changes in base salary, when appropriate.


GOALS

TARGET INCENTIVE - At the beginning of each Plan year, the Board shall establish
the target incentive levels for participants.  The target incentive (expressed
as a percent of salary) will vary according to the participant's duties and
responsibilities.

PERFORMANCE GOALS - The Board shall establish, at the beginning of each Plan
year, a planned level of performance at which participant bonus awards shall be
earned.  The Board also shall establish a range of performance levels at which
the maximum and minimum incentive awards shall be earned.

ADJUSTMENT OF PERFORMANCE TARGETS - The Board shall have the right to adjust the
performance goals (either up or down) during the Plan year if it determines that
external changes or other unanticipated business conditions have materially
affected the fairness of the goals and unduly influenced the Company's ability
to meet them.

At the end of each Plan year, final awards shall be computed for each
participant.  Participants must be actively employed by the Company on the last
day of the Plan year to receive an award for that Plan year.  Final award
amounts, may be adjusted (either up or down) based on the Board's assessment of
Company performance results.  Further, the Board shall have the right to adjust
the performance goals and the final award amounts in the event of a Plan year
consisting of less than twelve (12) months.

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MANAGEMENT INCENTIVE PLAN - JANUARY, 1997                                 PAGE 2
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HOW THE PLAN WORKS

1.  TARGET INCENTIVE - Target incentives are based on level of
responsibility, expressed as a percent of annual salary and represent a
reasonable and competitive incentive opportunity for the achievement of an
Earnings Per Share (EPS) goal pre-bonus for Corporate and EBIT goals for Area,
Region or Division.  January 1, 1997 base salary is used for calculations under
this plan, along with promotional adjustments or other salary changes that occur
during the Plan year.  Such changes will be made on pro-rata basis, using whole
months.  Participant target incentives are:
                                                    TARGET INCENTIVE EXPRESSED
           PARTICIPANT INCENTIVE CATEGORY              AS A % OF BASE SALARY
           ------------------------------              ---------------------

 Executive Vice Presidents                                   60.0%
 RVP's, Corp. Officers & Executive Committee Members         40.0%
 Other Officers / Staff Directors / Area Managers            33.0%
 Other Participants                                          20.0%, 15.0%, 10.0%

  The Chairman and Chief Executive Officer shall participate in this Plan,
  receiving incentive awards, as determined by the Board of Directors.

2.  WEIGHTING OF TARGET INCENTIVE -   The Plan contains an EPS goal to reward
    Corporate performance, EBIT goals to reward Area, Region or Division
    performance, and Safety goals to reward safety performance.  Participant's
    target incentives are weighted as follows:
<TABLE>
<CAPTION>                                    WEIGHTING BY ORGANIZATION LEVEL
            PARTICIPANTS        CORPORATE  AREA  REGION  DIVISION*  SAFETY PERFORMANCE**
     -----------------------------------------------------------------------------------

     <S>                          <C>      <C>   <C>        <C>             <C>
     Officers                     100%
     Corporate Staff              100%
     Area Managers                         50%    25%                       25%
     Region Staff                                100%
     Division Managers & Staff                    25%       50%             25%
</TABLE>

3.  POSSIBLE PAYOUTS (BASED ON PERFORMANCE) FOR CORPORATE, AREA, REGION OR
    DIVISION PERFORMANCE

    a) Corporate Performance will be calculated on Earnings Per Share (EPS)
using the following scale:

                                   EPS                 PAYOUT AS PERCENT OF
   LEVEL OF PERFORMANCE        PERFORMANCE           TARGET BONUS OPPORTUNITY
   --------------------        -----------           ------------------------

          Maximum                  109%                      150%
           Target                  100%                      100%
          Minimum                   96%                       50%

    b) Area, Region and Division performance will be calculated on the following
       scale.  Bonuses earned under this scale will be limited to the lesser of
       Corporate performance or actual Area, Region or Division performance
       achieved.  However, a "pool" will be established equal to field bonuses
       at the Corporate rate less field bonuses paid, to be shared among the
       field locations that performed at a rate higher than the Corporate rate.
                                   EBIT                PAYOUT AS PERCENT OF
   LEVEL OF PERFORMANCE    PERCENT OF PROFIT PLAN    TARGET BONUS OPPORTUNITY
   --------------------    ----------------------    ------------------------

          Maximum                  110%                      150%
          Target                   100%                      100%
          Minimum                   70%                       50%

    *  TWO FACILITIES IN ONE LOCATION ARE MEASURED SEPARATELY, I.E.,
       MINNEAPOLIS: BROOKLYN PARK & EAGAN, ETC.

   **  SAFETY TARGETS ARE PROVIDED THROUGH SEPARATE CORRESPONDENCE

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MANAGEMENT INCENTIVE PLAN - JANUARY, 1997                                 PAGE 3
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HOW THE PLAN WORKS (CONTINUED)


    c) Discretionary Award  -  A Discretionary bonus will be set aside for the
       use of the Compensation Committee of the Board of Directors to reward
       extraordinary performance at the Area, Region and Division level(s).
       Such discretionary bonus will be over and above any other bonus
       entitlements.



GENERAL PROVISIONS

OTHER

1.   The Compensation Committee shall review performance against goals at the
     conclusion of the plan and shall approve awards for individuals eligible to
     participate in this plan.

2.   The judgment of the Compensation Committee in construing this plan or any
     provision thereof, or in making any decision hereunder, shall be final and
     binding upon all participants and their beneficiaries, heirs, executors,
     personal representatives and assigns.

3.   Except as expressly provided in point 6 below, nothing herein contained
     shall limit or affect in any manner or degree the normal and usual powers
     of management, exercised by the Officers and the Board of Directors to
     change the duties or the character of employment of any employee of the
     Company or to remove the individual from the employment of the Company at
     any time, all of which rights and powers are expressly reserved.

4.   Except as expressly provided in point 6 below, no award will be paid an
     individual who is not a regular full time employee in good standing when
     the plan concludes, except an award may be considered in the event of
     retirement or death of a participant during the plan year, at the
     discretion of the Compensation Committee.

5.   Except as expressly provided in point 6 below, the awards to participants
     shall become a liability of the Company when the plan concludes, and all
     payments to be made hereunder will be made as soon as practicable
     thereafter.

6.   In the event the involuntary termination of a participant occurs prior to
     the conclusion of this plan, he or she may be entitled to payment of a
     reduced award for the year at the discretion of the Compensation Committee.
     Such award shall be paid to such employee as soon as practicable after
     awards have been approved.  For purposes of understanding "involuntary
     termination" shall mean actual or express termination of employment by the
     Company for its convenience, or any of its subsidiaries, provided, however,
     that in no event shall it include a termination based upon (a) any willful
     and continued failure to substantially perform assigned duties (other than
     as a result of incapacity) after demand giving specifics has been made for
     such performance, or (b) any willful misconduct which is materially
     injurious to the Company or any of its subsidiaries.  As used here, the
     word "willful" means any act done or omitted to be done not in good faith
     and without reasonable belief that such action or omission was in the best
     interest of the Company.