INSTRUMENT OF AMENDMENT TO THE
MDU RESOURCES GROUP, INC.
401(k) RETIREMENT PLAN

The MDU Resources Group, Inc. 401(k) Retirement Plan (as amended and restated
January 1, 2017) (the “K‑Plan”), is hereby amended, effective January 1, 2017,
as follows:

1.
By replacing the table in Section D-2-2 Eligibility to Share in the Retirement
Contribution of Supplement D-2, Provisions Relating to the Retirement
Contribution Feature for Certain Participating Affiliates, in its entirety, with
the following:

Participating Affiliate
Current Effective Date (Original Effective Date)
Retirement Contribution Amount - Percentage of Compensation
Cascade Natural Gas Corporation (non-bargaining)
January 1, 2011
(July 2, 2007)
5%
Cascade Natural Gas Corporation (Field Operations Bargaining Unit employees
hired on or after 1/1/2007)
May 1, 2015
(July 2, 2007)
5%
Great Plains Natural Gas Co.
January 1, 2003
5%
Intermountain Gas Company
January 1, 2011
(October 12, 2008)
5%
On Electric Group, Inc.
March 7, 2011
6%
Rocky Mountain Contractors, Inc.
(non-bargaining)
January 1, 2005
5%
WBI Energy Midstream, LLC1
July 1, 2012
(January 1, 2001)
5%

1The following participants of WBI Energy Midstream, LLC are excluded:, Grady
Breipohl, Jon Forbes, Richard Guderjahn, Steven Haag, Raymond Harms, Wade
Hasler, Douglas Henry, Pamela Lynn, Todd Mandeville, Marlin Mogan, and Dale
Sudbrack due to participation in the appropriate pension plan replacement
contribution.

Explanation: This amendment removes Fidelity Exploration & Production Company
(“FEP”) as a Participating Affiliate in the Retirement Contribution Feature,
effective January 1, 2017, as FEP no longer has any active employees
participating in the K-Plan.

2.
By replacing the first paragraph in Section D-6-2 Eligibility to Share in the
Retirement Contribution of Supplement D-6, Provisions Relating to the MDU
Resources Group, Inc. Retirement Contribution Feature, in its entirety, with the
following:

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D-6-2
Eligibility to Share in the Retirement Contribution. Participation in the
Retirement Contribution for any Plan Year is limited to employees who are hired
after December 31, 2005, and satisfy the Plan’s definition of Eligible Employee
for the following Participating Affiliates:

Knife River Corporation
MDU Construction Services Group, Inc.
MDU Resources Group, Inc.
Montana-Dakota Utilities Co.
WBI Energy, Inc.
WBI Energy Transmission, Inc.

Explanation: This amendment removes Prairielands Energy Marketing, Inc. (“PEMI”)
as a Participating Affiliate in the Retirement Contribution Feature, effective
January 1, 2017, as PEMI no longer has any active employees participating in the
K-Plan.

IN WITNESS WHEREOF, MDU Resources Group, Inc., as Sponsoring Employer of the
K-Plan, has caused this amendment to be duly executed by a member of the MDU
Resources Group, Inc. Employee Benefits Committee on this 31st day of March,
2017.

MDU RESOURCES GROUP, INC.
EMPLOYEE BENEFITS COMMITTEE
 
 
 
By: /s/ Doran N. Schwartz
Doran N. Schwartz, Chairman
 

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