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 May 1, 2018, as
follows:

 
1.
By adding the following to the table in Section D-1-2 Eligibility to Share in
the Profit Sharing Feature of Supplement D-1, Provisions Relating to the Profit
Sharing Feature for Certain Participating Affiliates:

Participating Affiliate
Current Effective Date
(Original Effective Date)
Knife River Corporation – Mountain West
May 1, 2018
(January 1, 2015)

 

Explanation: This amendment replaces Knife River Corporation – Northwest (the
Idaho Division) (“IDAHO”) with Knife River Corporation – Mountain West (KRC-MW)
as a Participating Affiliate in the Profit Sharing Feature, effective May 1,
2018, due to the Idaho Division of Knife River Corporation – Northwest being
spun off into a separate legal entity.

2.
By removing the following entry from the table in Section D-1-2 Eligibility to
Share in the Profit Sharing Feature of Supplement D-1, Provisions Relating to
the Profit Sharing Feature for Certain Participating Affiliates:

Participating Affiliate
Current Effective Date
(Original Effective Date)
Knife River Corporation – Northwest (the Idaho Division)
January 1, 2015

 

Explanation: This amendment removes IDAHO as a Participating Affiliate in the
Profit Sharing Feature, effective May 1, 2018, due to IDAHO being spun off into
a separate legal entity.

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3.
By removing the second entry in Schedule B and replacing it with the following:

Knife River Corporation – Mountain West (formerly known as Knife River
Corporation – Northwest (the Idaho Division) shall make supplemental
contributions on behalf of its Davis-Bacon Employees in such amounts as may be
necessary to satisfy the Prevailing Wage Law’s required fringe cost without
regard to any employer Matching and Profit Sharing Contributions pursuant to
Supplement G.

Effective May 1, 2018.

Explanation: This amendment revises Schedule B to reflect the Davis-Bacon
provisions for KRC-MW, effective May 1, 2018, due to IDAHO being spun off into a
separate legal entity.

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 25 day of April, 2018.

MDU RESOURCES GROUP, INC.
EMPLOYEE BENEFITS COMMITTEE

By: /s/Jason L. Vollmer
Jason L. Vollmer, Chairman

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