ex-10x.htm


    

      INSTRUMENT
OF AMENDMENT TO THE

      MDU
RESOURCES GROUP, INC.

      401(k)
RETIREMENT PLAN

      


      


      The MDU
Resources Group, Inc. 401(k) Retirement Plan as restated June 1, 2009 (the
“Plan”), is hereby further amended, effective January 1, 2010, as
follows:

      


      
        	
                1.  

              	
                By
      removing the definition of “Retirement” in Article I of the Plan and
      replacing it with a definition for “Normal Retirement Age” as
      follows:

              


      

      


      Normal Retirement Age
– The time a Participant attains age 60.

      


      Explanation:  This
amendment removes the reference to termination of employment after age 55, since
it does not have any relevance.  This clarifies eligibility to share
in Retirement Contributions and Profit Sharing Contributions, and for vesting
purposes.

      


      
        	
                2.  

              	
                By
      replacing Section D-4-2 Eligibility to Share
      in the Retirement Contribution, Special Transition Contribution, and
      Profit Sharing Feature of Supplement D-4 Provisions Relating to
      the Cascade Natural Gas Corporation Retirement Contribution, Special
      Transition Contribution, and Profit Sharing Contribution, in its
      entirety, with the following:

              


      

      


      
        	
                 
      

              	
                D-4-2

              	
                Eligibility to Share
      in the Retirement Contribution, Special Transition Contribution, and
      Profit Sharing Feature. In order to share in the allocation of any
      Retirement Contribution, Special Transition Contribution, or Profit
      Sharing Contribution made by Cascade pursuant to Paragraph 3 or 4 for a
      given Plan Year, a Participant must be an Eligible Employee of Cascade,
      complete 1,000 Hours of Service in that Plan Year, and be (a) a
      non-bargaining unit employee, (b) a part of the CSR Bargaining Unit
      (“CBU”), or (c) a part of the Field Operations Bargaining Unit
      (“FOBU”).  Effective as of January 1, 2008, a Participant must
      also be employed by Cascade on the last day of the Plan Year in order to
      be eligible to share in the allocation of a Profit Sharing Contribution
      for such Plan Year. However, any Participant who died or became disabled
      during the Plan Year, or terminated employment on or after attaining age
      60 is eligible to share in the Retirement Contribution or Profit Sharing
      Contribution, if any, for such Plan Year.  Participants who meet
      the preceding requirements are referred to herein as “Supplement D-4
      Participants.”

              


      

      


      Notwithstanding
the foregoing, certain identified Cascade employees who transfer to
Montana-Dakota Utilities Co. effective December 21, 2009 and remain employed on
December 31, 2009 shall be entitled to an allocation of the Profit Sharing
Contribution for the 2009 Plan Year.


      
        
           


        

        
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      Explanation:  This
amendment clarifies that employees who die, become disabled, or terminate
employment on or after age 60 (reduced from age 65) are not required to complete
1,000 hours of service in the Plan Year to receive the Retirement Contribution
or Profit Sharing Contribution.  This amendment also allows employees
who transfer from Cascade to Montana-Dakota Utilities on December 21, 2009 as a
result of  reorganization, to receive a Profit Sharing Contribution
from Cascade as long as they complete 1,000 hours of service and they are
employed by Montana-Dakota Utilities on December 31, 2009.

      


      
        	
                3.  

              	
                By
      replacing “age 65” with “age 60” throughout the
  Plan.

              


      

      


      Explanation: 
This amendment
reduces the age at which Participants who terminate employment are eligible to
share in Retirement and Profit Sharing Contributions for that Plan Year without
completing the 1,000 hours of service or end of year employment requirements. It
also reduces the age at which Participants become fully vested regardless of the
number of years of service.

      


      


      IN
WITNESS WHEREOF, MDU Resources Group, Inc., as Sponsoring Employer of the Plan,
has caused this Supplement to be duly executed by a member of the MDU Resources
Group, Inc. Employee Benefits Committee (“EBC”) on this 30th day of December,
2009.

      


      


      
        	 
      	
                MDU
      RESOURCES GROUP, INC.

              
	 
      	
                   EMPLOYEE
      BENEFITS COMMITTEE

              
	 
      	 
      	 
      
	 
      	 
      	 
      
	 
      	
                By:

              	
                /s/ Vernon A.
      Raile                           

              
	 
      	 
      	
                Vernon
      A. Raile, Chairman

              


      

      
        	
                 
      

              	
                 

              


      


      
        
           


        

        
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