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
March 1, 2011) (the “K-Plan”), is hereby further amended, as follows:

1.
Effective January 1, 2014, by replacing 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, in its
entirety, with the following:

Participating Affiliate
Current Effective Date
(Original Effective Date)2
Anchorage Sand & Gravel Company, Inc. (excluding President)
January 1, 1999
Baldwin Contracting Company, Inc.
January 1, 1999
Capital Electric Line Builders, Inc.1
January 1, 2014
Cascade Natural Gas Corporation
January 1, 2011
(July 2, 2007)
Concrete, Inc.
January 1, 2001
Connolly-Pacific Co.
January 1, 2007
DSS Company
January 1, 2004
(July 8, 1999)
E.S.I., Inc.
January 1, 2008
(January 1, 2003)
Fairbanks Materials, Inc.
May 1, 2008
Granite City Ready Mix, Inc.
June 1, 2002
Great Plains Natural Gas Co.
January 1, 2008

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Participating Affiliate
Current Effective Date
(Original Effective Date)2
Hawaiian Cement (non-union employees hired after December 31, 2005)
January 1, 2009
Intermountain Gas Company
January 1, 2011
JTL Group, Inc.5
January 1, 2014
Jebro Incorporated
November 1, 2005
Kent’s Oil Service4
January 1, 2007
Knife River Corporation – Northwest (the Central Oregon Division, f/k/a HTS)
January 1, 2010
(January 1, 1999)
Knife River Corporation – Northwest (the Southern Idaho Division)
January 1, 2010
(January 1, 2006)
Knife River Corporation – Northwest (the Southern Oregon Division)

January 1, 2012

Knife River Corporation – Northwest (the Spokane Division)
January 1, 2010
(January 1, 2006)
Knife River Corporation – Northwest (the Utah Division)

January 1, 2014

Knife River Corporation – Northwest (the Western Oregon Division)

January 1, 2012

Knife River Corporation - South
(f/k/a Young Contractors, Inc.)
January 1, 2008
(January 1, 2007)
LTM, Incorporated
January 1, 2003
Montana-Dakota Utilities Co. (including union employees)
January 1, 2008
Oregon Electric Construction, Inc.3
March 7, 2011
Wagner Industrial Electric, Inc.

January 1, 2008

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Participating Affiliate
Current Effective Date
(Original Effective Date)2
Wagner Smith Equipment Co.
January 1, 2008
(July 1, 2000)
WBI Energy, Inc.1/3
May 1, 2012
WBI Energy Midstream, LLC1/3
July 1, 2012
(January 1, 2001)
WBI Energy Midstream Utah, LLC1/3
August 1, 2014
WBI Energy Transmission, Inc.1/3
July 1, 2012
(January 1, 2009)
WHC, Ltd.
September 1, 2001

1/Eligible employees participating in a management incentive compensation plan
or an executive incentive compensation plan are not eligible for a Profit
Sharing Contribution. Employees of the WBI Energy Corrosion Services division of
WBI Energy Midstream, LLC are excluded from this feature.
2/In the event a Participating Affiliate adopts a Profit Sharing Feature on a
date other than January 1, effective as of the date of participation in the
Plan, the amount of any such contribution allocated to a Supplement D‑1
Participant shall be based upon Compensation, received while in the employ of
the Participating Affiliate after the date of acquisition by the Company or any
Affiliate.
3/Requirement to be an Active Employee on the last day of the Plan Year does not
apply.
4/The following participants of Kent’s Oil Service are granted vesting service
for prior years of service with Spirit Road Oils: Isaias Jaimes, Hideo Lewis,
Christopher Niffenegger, Jose Padilla, George Velador, and Anthony Willis.
5/Eligible JTL Casper hourly employees (both union and nonunion), including
those employees who participate in the Operating Engineers Local No. 800 & The
Wyoming Contractors’ Association, Inc. Pension Trust Fund for Wyoming (JTL MEP
employees.)
Explanation: This amendment adds Knife River Corporation – Northwest (Utah
Division) (“KR-Utah”) as a Participating Affiliate in Supplement D-1 (Profit
Sharing Feature) of the K‑Plan as of January 1, 2014, due to its desire to
participate in the Profit Sharing Feature.

2.
Effective January 1, 2015, by replacing 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, in its
entirety, with the following:

Participating Affiliate
Current Effective Date
(Original Effective Date)2
Anchorage Sand & Gravel Company, Inc. (excluding President)
January 1, 1999

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Participating Affiliate
Current Effective Date
(Original Effective Date)2
Baldwin Contracting Company, Inc.
January 1, 1999
Capital Electric Line Builders, Inc.1
January 1, 2014
Cascade Natural Gas Corporation
January 1, 2011
(July 2, 2007)
Concrete, Inc.
January 1, 2001
Connolly-Pacific Co.
January 1, 2007
DSS Company
January 1, 2004
(July 8, 1999)
E.S.I., Inc.
January 1, 2008
(January 1, 2003)
Fairbanks Materials, Inc.
May 1, 2008
Granite City Ready Mix, Inc.
June 1, 2002
Great Plains Natural Gas Co.
January 1, 2008
Hawaiian Cement (non-union employees hired after December 31, 2005)
January 1, 2009
Intermountain Gas Company
January 1, 2011
JTL Group, Inc.5/6
January 1, 2015
January 1, 2014
Jebro Incorporated
November 1, 2005
Kent’s Oil Service4
January 1, 2007
Knife River Corporation – Northwest (the Central Oregon Division, f/k/a HTS)
January 1, 2010
(January 1, 1999)

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Participating Affiliate
Current Effective Date
(Original Effective Date)2
Knife River Corporation – Northwest (the Idaho Division)
January 1, 2015
Knife River Corporation – Northwest (the Southern Oregon Division)

January 1, 2012

Knife River Corporation – Northwest (the Western Oregon Division)
January 1, 2012
Knife River Corporation - South
(f/k/a Young Contractors, Inc.)
January 1, 2008
(January 1, 2007)
LTM, Incorporated
January 1, 2003
Montana-Dakota Utilities Co. (including union employees)
January 1, 2008
Oregon Electric Construction, Inc.3
March 7, 2011
Wagner Industrial Electric, Inc.

January 1, 2008

Wagner Smith Equipment Co.
January 1, 2008
(July 1, 2000)
WBI Energy, Inc.1/3
May 1, 2012
WBI Energy Midstream, LLC1/3
July 1, 2012
(January 1, 2001)
WBI Energy Midstream Utah, LLC1/3
August 1, 2014
WBI Energy Transmission, Inc.1/3
July 1, 2012
(January 1, 2009)
WHC, Ltd.
September 1, 2001

1/Eligible employees participating in a management incentive compensation plan
or an executive incentive compensation plan are not eligible for a Profit
Sharing Contribution. Employees of the WBI Energy Corrosion Services division of
WBI Energy Midstream, LLC are excluded from this feature.
2/In the event a Participating Affiliate adopts a Profit Sharing Feature on a
date other than January 1, effective as of the date of participation in the
Plan, the amount of any such contribution allocated to a

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Supplement D‑1 Participant shall be based upon Compensation, received while in
the employ of the Participating Affiliate after the date of acquisition by the
Company or any Affiliate.
3/Requirement to be an Active Employee on the last day of the Plan Year does not
apply.
4/The following participants of Kent’s Oil Service are granted vesting service
for prior years of service with Spirit Road Oils: Isaias Jaimes, Hideo Lewis,
Christopher Niffenegger, Jose Padilla, George Velador, and Anthony Willis.
5/Eligible JTL Casper hourly employees (both union and nonunion), including
those employees who participate in the Operating Engineers Local No. 800 & The
Wyoming Contractors’ Association, Inc. Pension Trust Fund for Wyoming (JTL MEP
employees.)
6/Eligible salaried employees of JTL hired after December 31, 2014 or any other
JTL employee who transfers to a salaried position after December 31, 2014.

Explanation: This amendment adds Knife River Corporation – Northwest (Idaho
Division) (“KR-Idaho”) and removes the SID Idaho Division, Spokane Division, and
Utah Division as Participating Affiliates in Supplement D-1 (Profit Sharing
Feature) of the K‑Plan as the result of consolidation of divisions within KRC –
NW as of January 1, 2015. This amendment adds a Profit Sharing Feature for
salaried employees of JTL Group, Inc. hired after December 31, 2014 and any
other JTL employee who transfers to a salaried position after December 31, 2014.

3.
Effective January 1, 2015, by replacing Section D-7-3, Amount of Retirement
Contribution Allocation, of Supplement D-7, Provisions Relating to the JTL
Group, Inc. Retirement Contribution Feature, in its entirety, with the
following:

For each Plan Year, JTL shall provide eligible hourly Participants $1.55
(effective April 1, 2014) per hour of service as a Retirement Contribution. The
amount of any such contribution for a Plan Year will be allocated to Supplement
D-7 hourly Participants for each hour of service for which the Participant
receives compensation, excluding Hours of Service pursuant to a prevailing wage
agreement. In addition, JTL will credit eligible salaried Participants with a
contribution equal to eight percent (8%) of Compensation. Salaried Participants
must have been hired and classified as a salaried employee prior to January 1,
2015 in order to receive a Retirement Contribution allocation. The amount of any
such Retirement Contribution for a Plan Year shall be allocated to Supplement
D‑7 Participants based upon their Compensation, excluding bonuses received while
employed by the identified Participating Affiliate.

Explanation: This amendment closes the group of employees who receive the 8
percent Retirement Contribution. Any employee hired or who becomes classified as
salaried employee after December 31, 2014 will not be eligible to participate in
the Retirement Contribution Feature.

IN WITNESS WHEREOF, MDU Resources Group, Inc., as Sponsoring Employer of the
Plan, has caused this amendment to be duly executed by a member of the MDU
Resources Group, Inc. Employee Benefits Committee (“Committee”) on this 11th day
of

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December, 2014.

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

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