Wdesk | Document
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UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM 10-K
ý ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the fiscal year ended December 31, 2017
OR
o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from _____________ to ______________
Commission file number 1-03480
MDU RESOURCES GROUP, INC.
(Exact name of registrant as specified in its charter)
Delaware
 
41-0423660
(State or other jurisdiction of
incorporation or organization)
 
(I.R.S. Employer Identification No.)
1200 West Century Avenue
P.O. Box 5650
Bismarck, North Dakota 58506-5650
(Address of principal executive offices)
(Zip Code)
(701) 530-1000
(Registrant's telephone number, including area code)
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
 
Name of each exchange on which registered
Common Stock, par value $1.00
 
New York Stock Exchange
Securities registered pursuant to Section 12(g) of the Act: None
Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý No o.
Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Exchange Act. Yes o No ý.
Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý No o.
Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes ý No o.
Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of the registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act (Check one):
Large accelerated filer ý
Accelerated filer o
Non-accelerated filer o  (Do not check if a smaller reporting company)
Smaller reporting company o
 
Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No ý.
State the aggregate market value of the voting common stock held by nonaffiliates of the registrant as of June 30, 2017: $5,116,974,651.
Indicate the number of shares outstanding of the registrant's common stock, as of February 15, 2018: 195,304,376 shares.
DOCUMENTS INCORPORATED BY REFERENCE
Relevant portions of the registrant's 2018 Proxy Statement, to be filed no later than 120 days from December 31, 2017, are incorporated by reference in Part III, Items 10, 11, 12, 13 and 14 of this Report.




Contents
 

Part I
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Item 1A
 
 
 
Item 1B
 
 
 
Item 3
 
 
 
Item 4
 
 
 
Part II
 
 
 
 
Item 5
 
 
 
Item 6
 
 
 
Item 7
 
 
 
Item 7A
 
 
 
Item 8
 
 
 
Item 9
 
 
 
Item 9A
 
 
 
Item 9B
 
 
 
Part III
 
 
 
 
Item 10
 
 
 
Item 11
 
 
 
Item 12
 
 
 
Item 13
 
 
 
Item 14
 
 
 
Part IV
 
 
 
 
Item 15
 
 
 
Item 16
 
 
 
 
 
 
 
 

 
2 MDU Resources Group, Inc. Form 10-K



Definitions
 

The following abbreviations and acronyms used in this Form 10-K are defined below:
Abbreviation or Acronym
 
AFUDC
Allowance for funds used during construction
Andeavor Field Services LLC
Formerly QEP Field Services, LLC doing business as Tesoro Logistics Rockies LLC
Army Corps
U.S. Army Corps of Engineers
ASC
FASB Accounting Standards Codification
ATBs
Atmospheric tower bottoms
Bcf
Billion cubic feet
Big Stone Station
475-MW coal-fired electric generating facility near Big Stone City, South Dakota (22.7 percent ownership)
Brazilian Transmission Lines
Company's former investment in companies owning three electric transmission lines in Brazil
Btu
British thermal unit
Calumet
Calumet Specialty Products Partners, L.P.
Capital Electric
Capital Electric Construction Company, Inc., a direct wholly owned subsidiary of MDU Construction Services
Cascade
Cascade Natural Gas Corporation, an indirect wholly owned subsidiary of MDU Energy Capital
Centennial
Centennial Energy Holdings, Inc., a direct wholly owned subsidiary of the Company
Centennial Capital
Centennial Holdings Capital LLC, a direct wholly owned subsidiary of Centennial
Centennial's Consolidated EBITDA
Centennial's consolidated net income from continuing operations plus the related interest expense, taxes, depreciation, depletion, amortization of intangibles and any non-cash charge relating to asset impairment for the preceding 12-month period
Centennial Resources
Centennial Energy Resources LLC, a direct wholly owned subsidiary of Centennial
CERCLA
Comprehensive Environmental Response, Compensation and Liability Act
Clean Air Act
Federal Clean Air Act
Clean Water Act
Federal Clean Water Act
Company
MDU Resources Group, Inc.
Coyote Creek
Coyote Creek Mining Company, LLC, a subsidiary of The North American Coal Corporation
Coyote Station
427-MW coal-fired electric generating facility near Beulah, North Dakota (25 percent ownership)
Dakota Prairie Refinery
20,000-barrel-per-day diesel topping plant built by Dakota Prairie Refining in southwestern North Dakota
Dakota Prairie Refining
Dakota Prairie Refining, LLC, a limited liability company previously owned by WBI Energy and Calumet (previously included in the Company's refining segment)
D.C. Circuit Court
United States Court of Appeals for the District of Columbia Circuit
dk
Decatherm
Dodd-Frank Act
Dodd-Frank Wall Street Reform and Consumer Protection Act
EBITDA
Earnings before interest, taxes, depreciation, depletion and amortization
EIN
Employer Identification Number
EPA
United States Environmental Protection Agency
ERISA
Employee Retirement Income Security Act of 1974
ESA
Endangered Species Act
Exchange Act
Securities Exchange Act of 1934, as amended
FASB
Financial Accounting Standards Board
FERC
Federal Energy Regulatory Commission
Fidelity
Fidelity Exploration & Production Company, a direct wholly owned subsidiary of WBI Holdings (previously referred to as the Company's exploration and production segment)
FIP
Funding improvement plan
GAAP
Accounting principles generally accepted in the United States of America
GHG
Greenhouse gas
Great Plains
Great Plains Natural Gas Co., a public utility division of the Company
GVTC
Generation Verification Test Capacity
IBEW
International Brotherhood of Electrical Workers
ICWU
International Chemical Workers Union
IFRS
International Financial Reporting Standards

 
MDU Resources Group, Inc. Form 10-K 3



Definitions
 

Intermountain
Intermountain Gas Company, an indirect wholly owned subsidiary of MDU Energy Capital
IPUC
Idaho Public Utilities Commission
Item 8
Financial Statements and Supplementary Data
Knife River
Knife River Corporation, a direct wholly owned subsidiary of Centennial
Knife River - Northwest
Knife River Corporation - Northwest, an indirect wholly owned subsidiary of Knife River
K-Plan
Company's 401(k) Retirement Plan
kW
Kilowatts
kWh
Kilowatt-hour
LWG
Lower Willamette Group
MD&A
Management's Discussion and Analysis of Financial Condition and Results of Operations
Mdk
Thousand dk
MDU Construction Services
MDU Construction Services Group, Inc., a direct wholly owned subsidiary of Centennial
MDU Energy Capital
MDU Energy Capital, LLC, a direct wholly owned subsidiary of the Company
MEPP
Multiemployer pension plan
MISO
Midcontinent Independent System Operator, Inc.
MMBtu
Million Btu
MMdk
Million dk
MNPUC
Minnesota Public Utilities Commission
Montana-Dakota
Montana-Dakota Utilities Co., a public utility division of the Company
Montana DEQ
Montana Department of Environmental Quality
MPPAA
Multiemployer Pension Plan Amendments Act of 1980
MTPSC
Montana Public Service Commission
MW
Megawatt
NDPSC
North Dakota Public Service Commission
NGL
Natural gas liquids
Oil
Includes crude oil and condensate
OPUC
Oregon Public Utility Commission
Oregon DEQ
Oregon State Department of Environmental Quality
PCBs
Polychlorinated biphenyls
Pronghorn
Natural gas processing plant located near Belfield, North Dakota (WBI Energy Midstream's 50 percent ownership interests were sold effective January 1, 2017)
Proxy Statement
Company's 2018 Proxy Statement
PRP
Potentially Responsible Party
RCRA
Resource Conservation and Recovery Act
ROD
Record of Decision
RP
Rehabilitation plan
SDPUC
South Dakota Public Utilities Commission
SEC
United States Securities and Exchange Commission
SEC Defined Prices
The average price of oil and natural gas during the applicable 12-month period, determined as an unweighted arithmetic average of the first-day-of-the-month price for each month within such period, unless prices are defined by contractual arrangements, excluding escalations based upon future conditions
Securities Act
Securities Act of 1933, as amended
Securities Act Industry Guide 7
Description of Property by Issuers Engaged or to be Engaged in Significant Mining Operations
Sheridan System
A separate electric system owned by Montana-Dakota
South Dakota DENR
South Dakota Department of Environment and Natural Resources
SSIP
System Safety and Integrity Program
Stock Purchase Plan
Company's Dividend Reinvestment and Direct Stock Purchase Plan which was terminated effective December 5, 2016
TCJA
Tax Cuts and Jobs Act
Tesoro
Tesoro Refining & Marketing Company LLC
Thurston County Superior Court
State of Washington Thurston County Superior Court

 
4 MDU Resources Group, Inc. Form 10-K



Definitions
 

UA
United Association of Journeyman and Apprentices of the Plumbing and Pipefitting Industry of the United States and Canada
United States Supreme Court
Supreme Court of the United States
VIE
Variable interest entity
Washington DOE
Washington State Department of Ecology
WBI Energy
WBI Energy, Inc., a direct wholly owned subsidiary of WBI Holdings
WBI Energy Midstream
WBI Energy Midstream, LLC, an indirect wholly owned subsidiary of WBI Holdings
WBI Energy Transmission
WBI Energy Transmission, Inc., an indirect wholly owned subsidiary of WBI Holdings
WBI Holdings
WBI Holdings, Inc., a direct wholly owned subsidiary of Centennial
WUTC
Washington Utilities and Transportation Commission
Wygen III
100-MW coal-fired electric generating facility near Gillette, Wyoming (25 percent ownership)
WYPSC
Wyoming Public Service Commission
ZRCs
Zonal resource credits - a MW of demand equivalent assigned to generators by MISO for meeting system reliability requirements

 
MDU Resources Group, Inc. Form 10-K 5



Part I
 


Forward-Looking Statements
This Form 10-K contains forward-looking statements within the meaning of Section 21E of the Exchange Act. Forward-looking statements are all statements other than statements of historical fact, including without limitation those statements that are identified by the words "anticipates," "estimates," "expects," "intends," "plans," "predicts" and similar expressions, and include statements concerning plans, objectives, goals, strategies, future events or performance, and underlying assumptions (many of which are based, in turn, upon further assumptions) and other statements that are other than statements of historical facts. From time to time, the Company may publish or otherwise make available forward-looking statements of this nature, including statements contained within Item 7 - MD&A - Business Segment Financial and Operating Data.
Forward-looking statements involve risks and uncertainties, which could cause actual results or outcomes to differ materially from those expressed. The Company's expectations, beliefs and projections are expressed in good faith and are believed by the Company to have a reasonable basis, including without limitation, management's examination of historical operating trends, data contained in the Company's records and other data available from third parties. Nonetheless, the Company's expectations, beliefs or projections may not be achieved or accomplished.
Any forward-looking statement contained in this document speaks only as of the date on which the statement is made, and the Company undertakes no obligation to update any forward-looking statement or statements to reflect events or circumstances that occur after the date on which the statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time, and it is not possible for management to predict all of the factors, nor can it assess the effect of each factor on the Company's business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statement. All forward-looking statements, whether written or oral and whether made by or on behalf of the Company, are expressly qualified by the risk factors and cautionary statements in this Form 10-K, including statements contained within Item 1A - Risk Factors.
Items 1 and 2. Business and Properties
General
The Company is a regulated energy delivery and construction materials and services business, which was incorporated under the laws of the state of Delaware in 1924. Its principal executive offices are at 1200 West Century Avenue, P.O. Box 5650, Bismarck, North Dakota 58506-5650, telephone (701) 530-1000.
The Company operates with a two-platform business model. Its regulated energy delivery platform and its construction materials and services platform are each comprised of different operating segments. Some of these segments experience seasonality related to the industries in which they operate. The two-platform approach helps balance this seasonality and the risk associated with each type of industry. Through its regulated energy delivery platform, the Company provides electric and natural gas services to customers, generates, transmits and distributes electricity, and provides natural gas transportation, storage and gathering services. These businesses are regulated by state public service commissions and/or the FERC. The construction materials and services platform provides construction services to a variety of industries, including commercial, industrial and governmental, and provides construction materials through aggregate mining and marketing of related products, such as ready-mix concrete and asphalt.
The Company is organized into five reportable business segments. These business segments include: electric, natural gas distribution, pipeline and midstream, construction materials and contracting, and construction services. The Company's reportable segments are determined based on the Company's method of internal reporting, which generally segregates the strategic business units due to differences in products, services and regulation. The internal reporting of these segments is defined based on the reporting and review process used by the Company's chief executive officer.
Montana-Dakota, Great Plains, Cascade and Intermountain comprise the natural gas distribution segment. Montana-Dakota also comprises the electric segment.
The Company, through its wholly owned subsidiary, Centennial, owns WBI Holdings, Knife River, MDU Construction Services, Centennial Resources and Centennial Capital. WBI Holdings is the pipeline and midstream segment, Knife River is the construction materials and contracting segment, MDU Construction Services is the construction services segment, and Centennial Resources and Centennial Capital are both reflected in the Other category.
On November 21, 2017, the Company announced that its board of directors has directed senior management to explore reorganization to a holding company structure. The purpose of a potential reorganization would be to make Montana-Dakota and Great Plains, which today are

 
6 MDU Resources Group, Inc. Form 10-K



Part I
 

divisions of the Company, into a subsidiary of the holding company, just as the Company’s other operating companies are wholly owned subsidiaries.
For more information on the Company's business segments and discontinued operations, see Item 8 - Notes 2 and 13.
As of December 31, 2017, the Company had 10,140 employees with 205 employed at MDU Resources Group, Inc., 963 at Montana-Dakota, 35 at Great Plains, 348 at Cascade, 240 at Intermountain, 319 at WBI Holdings, 3,466 at Knife River and 4,564 at MDU Construction Services. The number of employees at certain Company operations fluctuates during the year depending upon the number and size of construction projects. The Company considers its relations with employees to be satisfactory.
The following information regarding the number of employees represented by labor contracts is as of December 31, 2017.
At Montana-Dakota and WBI Energy Transmission, 353 and 68 employees, respectively, are represented by the IBEW. Labor contracts with such employees are in effect through April 30, 2018, and March 31, 2018, respectively.
At Cascade, 192 employees are represented by the ICWU. The labor contract with the field operations group is effective through March 31, 2018.
At Intermountain, 127 employees are represented by the UA. Labor contracts with such employees are in effect through September 30, 2019.
Knife River operates under 43 labor contracts that represent 685 of its construction materials and contracting employees. Knife River is in negotiations on one of its labor contracts.
MDU Construction Services has 130 labor contracts representing the majority of its employees. MDU Construction Services is in negotiations on 10 of its labor contracts.
The majority of the labor contracts contain provisions that prohibit work stoppages or strikes and provide for binding arbitration dispute resolution in the event of an extended disagreement.
The Company's principal properties, which are of varying ages and are of different construction types, are generally in good condition, are well maintained and are generally suitable and adequate for the purposes for which they are used.
The financial results and data applicable to each of the Company's business segments, as well as their financing requirements, are set forth in Item 7 - MD&A and Item 8 - Note 13 and Supplementary Financial Information.
The operations of the Company and certain of its subsidiaries are subject to federal, state and local laws and regulations providing for air, water and solid waste pollution control; state facility-siting regulations; zoning and planning regulations of certain state and local authorities; federal health and safety regulations and state hazard communication standards. The Company believes that it is in substantial compliance with these regulations, except as to what may be ultimately determined with regard to items discussed in Environmental matters in Item 8 - Note 17. There are no pending CERCLA actions for any of the Company's properties, other than the Portland, Oregon, Harbor Superfund Site and the Bremerton Gasworks Superfund Site.
The Company produces GHG emissions primarily from its fossil fuel electric generating facilities, as well as from natural gas pipeline and storage systems, and operations of equipment and fleet vehicles. GHG emissions also result from customer use of natural gas for heating and other uses. As interest in reductions in GHG emissions has grown, the Company has developed renewable generation with lower or no GHG emissions. Governmental legislative and regulatory initiatives regarding environmental and energy policy are continuously evolving and could negatively impact the Company's operations and financial results. Until legislation and regulation are finalized, the impact of these measures cannot be accurately predicted. The Company will continue to monitor legislative and regulatory activity related to environmental and energy policy initiatives. Disclosure regarding specific environmental matters applicable to each of the Company's businesses is set forth under each business description later. In addition, for a discussion of the Company's risks related to environmental laws and regulations, see Item 1A - Risk Factors.
This annual report on Form 10-K, the Company's quarterly reports on Form 10-Q and current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act are available free of charge through the Company's Web site as soon as reasonably practicable after the Company has electronically filed such reports with, or furnished such reports to, the SEC. The Company's Web site address is www.mdu.com. The information available on the Company's Web site is not part of this annual report on Form 10-K.

 
MDU Resources Group, Inc. Form 10-K 7



Part I
 

Electric
General Montana-Dakota provides electric service at retail, serving 142,901 residential, commercial, industrial and municipal customers in 178 communities and adjacent rural areas as of December 31, 2017. For more information on the retail customer classes served, see the table below. The principal properties owned by Montana-Dakota for use in its electric operations include interests in 16 electric generating units at 11 facilities and three small portable diesel generators, as further described under System Supply, System Demand and Competition, approximately 3,200 and 4,900 miles of transmission and distribution lines, respectively, and 73 transmission and 296 distribution substations. Montana-Dakota has obtained and holds, or is in the process of renewing, valid and existing franchises authorizing it to conduct its electric operations in all of the municipalities it serves where such franchises are required. Montana-Dakota intends to protect its service area and seek renewal of all expiring franchises. At December 31, 2017, Montana-Dakota's net electric plant investment was $1.4 billion, and rate base was $1.1 billion.

The retail customers served and respective revenues by class for the electric business were as follows:
 
2017
2016
2015
 
Customers
Served

Revenues

Customers
Served

Revenues

Customers
Served

Revenues

 
(Dollars in thousands)
Residential
118,379

$
121,171

118,483

$
117,014

118,413

$
107,767

Commercial
22,764

140,856

22,693

135,390

22,423

121,463

Industrial
242

34,417

244

31,913

240

32,786

Other
1,516

8,275

1,528

7,580

1,511

6,791

 
142,901

$
304,719

142,948

$
291,897

142,587

$
268,807

Other electric revenues for Montana-Dakota were $38.1 million, $30.4 million and $11.8 million for the years ended December 31, 2017, 2016 and 2015, respectively.
The percentage of electric retail revenues by jurisdiction was as follows:
 
2017

2016

2015

North Dakota
66
%
68
%
65
%
Montana
20
%
19
%
21
%
Wyoming
9
%
8
%
9
%
South Dakota
5
%
5
%
5
%
Retail electric rates, service, accounting and certain security issuances are subject to regulation by the MTPSC, NDPSC, SDPUC and WYPSC. The interstate transmission and wholesale electric power operations of Montana-Dakota also are subject to regulation by the FERC under provisions of the Federal Power Act, as are interconnections with other utilities and power generators, the issuance of securities, accounting and other matters.
Through MISO, Montana-Dakota has access to wholesale energy, ancillary services and capacity markets for its interconnected system. MISO is a regional transmission organization responsible for operational control of the transmission systems of its members. MISO provides security center operations, tariff administration and operates day-ahead and real-time energy markets, ancillary services and capacity markets. As a member of MISO, Montana-Dakota's generation is sold into the MISO energy market and its energy needs are purchased from that market.
System Supply, System Demand and Competition Through an interconnected electric system, Montana-Dakota serves markets in portions of western North Dakota, including Bismarck, Mandan, Dickinson, Williston and Watford City; eastern Montana, including Sidney, Glendive and Miles City; and northern South Dakota, including Mobridge. The interconnected system consists of 15 electric generating units at 10 facilities and three small portable diesel generators, which have an aggregate nameplate rating attributable to Montana-Dakota's interest of 704,143 kW and total net ZRCs of 528.2 in 2017. ZRCs are a MW of demand equivalent measure and are allocated to individual generators to meet planning reserve margin requirements within MISO. For 2017, Montana-Dakota's total ZRCs, including its firm purchase power contracts, were 553.1. Montana-Dakota's planning reserve margin requirement within MISO was 530.2 for 2017. The maximum electric peak demand experienced to date attributable to Montana-Dakota's sales to retail customers on the interconnected system was 611,542 kW in August 2015. Montana-Dakota's latest forecast for its interconnected system indicates that its annual peak will continue to occur during the summer and the sales growth rate through 2022 will approximate two percent annually. Montana-Dakota's interconnected system electric generating capability includes five steam-turbine generating units at four facilities using coal for fuel, four combustion

 
8 MDU Resources Group, Inc. Form 10-K



Part I
 

turbine units at three facilities, three wind electric generating facilities, two reciprocating internal combustion engines at one facility, a heat recovery electric generating facility and three small portable diesel generators.
In June 2016, Montana-Dakota and a partner began construction on a 345-kilovolt transmission line within the footprint of MISO from Ellendale, North Dakota, to Big Stone City, South Dakota, a distance of about 160 miles, which will facilitate public policy goals and objectives, including delivery of renewable wind energy from North Dakota to eastern markets. The project has been approved as a MISO multivalue project. All necessary easements have been secured and the project is expected to be completed in 2019.
In December 2016, Montana-Dakota signed a 25-year agreement to purchase power from the expansion of the Thunder Spirit Wind farm in southwest North Dakota. In November 2017, the NDPSC approved the advance determination of prudence for the purchase of the Thunder Spirit Wind farm expansion. Montana-Dakota expects to soon have a purchase agreement in place and finalize the purchase when the construction is complete in late 2018. With the addition of the expansion, Montana-Dakota's total wind farm generation capacity will be approximately 155 MW and increase Montana-Dakota's electric generation portfolio to approximately 27 percent renewables. The original 107.5-MW wind farm includes 43 turbines; it was purchased by Montana-Dakota in December 2015. The expansion will include 16 turbines. Acquisition costs for the project are estimated to be approximately $85 million.
Additional energy will be purchased as needed, or if more economical, from the MISO market. In 2017, Montana-Dakota purchased approximately 26 percent of its net kWh needs for its interconnected system through the MISO market.
Approximately 24 percent of the electricity delivered to customers from Montana-Dakota's owned generation in 2017 was from renewable resources. Although Montana-Dakota's generation resource capacity has increased to serve the needs of customers, the carbon dioxide emission intensity of the electric generation resource fleet has been reduced by more than 25 percent since 2003 and is expected to continue to decline.
Through the Sheridan System, Montana-Dakota serves Sheridan, Wyoming, and neighboring communities. The maximum peak demand experienced to date attributable to Montana-Dakota sales to retail customers on that system was approximately 61,501 kW in July 2012. Montana-Dakota has a power supply contract with Black Hills Power, Inc. to purchase up to 49,000 kW of capacity annually through December 31, 2023. Wygen III serves a portion of the needs of its Sheridan-area customers.

 
MDU Resources Group, Inc. Form 10-K 9



Part I
 

The following table sets forth details applicable to the Company's electric generating stations:
Generating Station
Type
Nameplate Rating (kW)

2017 ZRCs

(a) 
2017 Net Generation (kWh in thousands)

Interconnected System:
 
 
 
 
 
North Dakota:
 
 
 
 
 
Coyote (b)
Steam
103,647

83.4

 
652,071

Heskett
Steam
86,000

87.1

 
454,134

Heskett
Combustion Turbine
89,038

59.0

 
3,400

Glen Ullin
Heat Recovery
7,500

4.0

 
45,548

Cedar Hills
Wind
19,500

5.0

 
59,385

Diesel Units
Oil
5,475

3.7

 
9

Thunder Spirit
Wind
107,500

20.6

 
428,528

South Dakota:
 
 
 
 
 
Big Stone (b)
Steam
94,111

101.8

 
469,709

Montana:
 
 
 
 
 
Lewis & Clark
Steam
44,000

50.9

 
225,984

Lewis & Clark
Reciprocating Internal Combustion Engine
18,700

16.1

 
5,453

Glendive
Combustion Turbine
75,522

68.8

 
2,333

Miles City
Combustion Turbine
23,150

21.5

 
406

Diamond Willow
Wind
30,000

6.3

 
93,696

 
 
704,143

528.2

 
2,440,656

Sheridan System:
 
 

 

 
 

Wyoming:
 
 
 
 
 

Wygen III (b)
Steam
28,000

N/A

 
189,984

 
 
732,143

528.2

 
2,630,640

(a)
Interconnected system only. MISO requires generators to obtain their summer capability through the GVTC. The GVTC is then converted to ZRCs by applying each generator's forced outage factor against its GVTC. Wind generator's ZRCs are calculated based on a wind capacity study performed annually by MISO. ZRCs are used to meet supply obligations within MISO.
(b)
Reflects Montana-Dakota's ownership interest.
 
Virtually all of the current fuel requirements of the Heskett and Lewis & Clark stations are met with coal supplied by subsidiaries of Westmoreland Coal Company under contracts that expire in December 2021 and December 2020, respectively. The Heskett and Lewis & Clark coal supply agreements provide for the purchase of coal necessary to supply the coal requirements of these stations at contracted pricing. Montana-Dakota estimates the Heskett and Lewis & Clark coal requirement to be in the range of 425,000 to 460,000 tons and 250,000 to 350,000 tons per contract year, respectively.
The owners of Coyote Station, including Montana-Dakota, have a contract with Coyote Creek for coal supply to the Coyote Station that expires December 2040. Montana-Dakota estimates the Coyote Station coal supply agreement to be approximately 2.5 million tons per contract year. For more information, see Item 8 - Note 17.
The owners of Big Stone Station, including Montana-Dakota, have coal supply agreements, which meet a portion of the Big Stone Station's fuel requirements, for the purchase of 250,000 tons in 2018 and 2019 from Contura Coal Sales, LLC and 550,000 tons in 2018 from Peabody COALSALES, LLC both at contracted pricing. The remainder of the Big Stone Station fuel requirements will be secured through separate future contracts.
Montana-Dakota has a coal supply agreement with Wyodak Resources Development Corp., to supply the coal requirements of Wygen III at contracted pricing through June 1, 2060. Montana-Dakota estimates the maximum annual coal consumption of the facility to be 585,000 tons.
The average cost of coal purchased, including freight, at Montana-Dakota's electric generating stations (including the Big Stone, Coyote and Wygen III stations) was as follows:
Years ended December 31,
2017

2016

2015

Average cost of coal per MMBtu
$
2.07

$
1.89

$
1.75

Average cost of coal per ton
$
30.04

$
27.45

$
25.41


 
10 MDU Resources Group, Inc. Form 10-K



Part I
 

Montana-Dakota expects that it has secured adequate capacity available through existing baseload generating stations, renewable generation, turbine peaking stations, demand reduction programs and firm contracts to meet the peak customer demand requirements of its customers through 2024. Future capacity that is needed to replace contracts and meet system growth requirements is expected to be met by constructing new generation resources, or acquiring additional capacity through power purchase contracts or the MISO capacity auction.
Montana-Dakota has major interconnections with its neighboring utilities and considers these interconnections adequate for coordinated planning, emergency assistance, exchange of capacity and energy and power supply reliability.
Montana-Dakota is subject to competition in varying degrees, in certain areas, from rural electric cooperatives, on-site generators, co-generators and municipally owned systems. In addition, competition in varying degrees exists between electricity and alternative forms of energy such as natural gas.
Regulatory Matters and Revenues Subject to Refund In North Dakota, Montana-Dakota's results of operations reflect monthly increases or decreases in electric fuel and purchased power costs (including demand charges) and Montana-Dakota is deferring those electric fuel and purchased power costs that are greater or less than amounts presently being recovered through its existing rate schedules. In Montana, a monthly Fuel and Purchased Power Tracking Adjustment mechanism allows Montana-Dakota's results of operations to reflect 90 percent of the increases or decreases in electric fuel and purchased power costs (including demand charges) and Montana-Dakota is deferring 90 percent of costs that are greater or less than amounts presently being recovered through its existing rate schedules. A fuel adjustment clause contained in South Dakota jurisdictional electric rate schedules allows Montana-Dakota's results of operations to reflect monthly increases or decreases in electric fuel and purchased power costs. In Wyoming, an annual Electric Power Supply Cost Adjustment mechanism allows Montana-Dakota's results of operations to reflect increases or decreases in purchased power costs (including demand charges) related to power supply and Montana-Dakota is deferring costs that are greater or less than amounts presently being recovered through its existing rate schedules. Such orders generally provide that these amounts are recoverable or refundable through rate adjustments which are filed annually. Montana-Dakota's results of operations reflect 95 percent of the increases or decreases from the base purchased power costs and in addition also reflects 85 percent of the increases or decreases from the base coal price, which is also recovered through the Electric Power Supply Cost Adjustment. For more information, see Item 8 - Note 4.
For the Thunder Spirit Wind project, Montana-Dakota implemented a renewable resource cost adjustment rider, and all of Montana-Dakota's wind resources pertaining to North Dakota electric operations were placed in this rider upon a final order of the most recent North Dakota electric general rate case. Montana-Dakota also has in place in North Dakota a transmission tracker to recover transmission costs associated with MISO and the Southwest Power Pool, regional transmission systems serving Montana-Dakota, along with certain of the transmission investments not recovered through retail rates. The tracking mechanism has an annual true-up.
In South Dakota, Montana-Dakota recovers the South Dakota investment in the Thunder Spirit Wind project through an Infrastructure Rider tracking mechanism that is subject to an annual true-up. Montana-Dakota also has in place in South Dakota a transmission tracker to recover transmission costs associated with MISO and the Southwest Power Pool, regional transmission systems serving Montana-Dakota, along with certain of the transmission investments not recovered through retail rates. The tracking mechanism has an annual true-up.
In Montana, Montana-Dakota recovers in rates through a tracking mechanism the increases associated with its allocated share of Montana state and local taxes assessed to electric operations on an after tax basis.
For more information on regulatory matters, see Item 8 - Note 16.
Environmental Matters Montana-Dakota's electric operations are subject to federal, state and local laws and regulations providing for air, water and solid waste pollution control; state facility-siting regulations; zoning and planning regulations of certain state and local authorities; federal health and safety regulations; and state hazard communication standards. Montana-Dakota believes it is in substantial compliance with these regulations.
Montana-Dakota's electric generating facilities have Title V Operating Permits, under the Clean Air Act, issued by the states in which they operate. Each of these permits has a five-year life. Near the expiration of these permits, renewal applications are submitted. Permits continue in force beyond the expiration date, provided the application for renewal is submitted by the required date, usually six months prior to expiration. The Title V Operating Permit renewal application for Big Stone Station was submitted timely to the South Dakota DENR in November 2013, and a final permit was issued in May 2017. An application to modify the Title V Operating Permit for incorporation of two new natural gas-fired engines at Lewis & Clark Station was submitted to the Montana DEQ timely in December 2016, and a final permit was issued in July 2017. The Title V Operating Permit renewal application for Coyote Station was submitted timely to the North Dakota Department of Health in September 2017, with the permit expected to be issued in 2018. Wygen III is allowed to operate under the facility's construction permit until the Title V Operating Permit is issued by the Wyoming Department of Environmental Quality. The Title V Operating Permit application for Wygen III was submitted timely in January 2011, with the permit expected to be issued in 2018.

 
MDU Resources Group, Inc. Form 10-K 11



Part I
 

State water discharge permits issued under the requirements of the Clean Water Act are maintained for power production facilities on the Yellowstone and Missouri rivers. These permits also have five-year lives. Montana-Dakota renews these permits as necessary prior to expiration. Other permits held by these facilities may include an initial siting permit, which is typically a one-time, preconstruction permit issued by the state; state permits to dispose of combustion by-products; state authorizations to withdraw water for operations; and Army Corps permits to construct water intake structures. Montana-Dakota's Army Corps permits grant one-time permission to construct and do not require renewal. Other permit terms vary and the permits are renewed as necessary.
Montana-Dakota's electric operations are conditionally exempt small-quantity hazardous waste generators and subject only to minimum regulation under the RCRA. Montana-Dakota routinely handles PCBs from its electric operations in accordance with federal requirements. PCB storage areas are registered with the EPA as required.
Montana-Dakota incurred $3.7 million of environmental capital expenditures in 2017, mainly for coal ash management projects at Lewis & Clark Station, Big Stone Station and Coyote Station. Environmental capital expenditures are estimated to be $9.6 million, $9.2 million and $1.5 million in 2018, 2019 and 2020, respectively, for various environmental upgrades and improvements for air emission and water and coal ash management at power plants. Montana-Dakota's capital and operational expenditures could also be affected by future air emission regulations, including a future regulation that may replace the Clean Power Plan rule published by the EPA in October 2015. The Clean Power Plan requires existing fossil fuel-fired electric generating facilities to reduce carbon dioxide emissions. On February 9, 2016, the United States Supreme Court granted an application for a stay of the Clean Power Plan pending disposition of the applicants' petition for review in the D.C. Circuit Court and disposition of the applicants' petition for a writ of certiorari if such a writ is sought. The EPA filed a motion with the D.C. Circuit Court on March 28, 2017, requesting the Clean Power Plan's case be held in abeyance. The D.C. Circuit Court granted the EPA’s motion to hold the case in abeyance for 60 days. On August 8, 2017, the D.C. Circuit Court issued an order holding the case in abeyance for an additional 60-day period and directed the EPA to file status reports at 30-day intervals. In parallel, the EPA published a proposal on October 16, 2017, to repeal the Clean Power Plan in its entirety and followed with an advance notice of proposed rulemaking published in the Federal Register on December 28, 2017, requesting comment on replacing the Clean Power Plan through new rulemaking.
Natural Gas Distribution
General The Company's natural gas distribution operations consist of Montana-Dakota, Great Plains, Cascade and Intermountain, which sell natural gas at retail, serving 938,867 residential, commercial and industrial customers in 335 communities and adjacent rural areas across eight states as of December 31, 2017, and provide natural gas transportation services to certain customers on the Company's systems. For more information on the retail customer classes served, see the table below. These services are provided through distribution systems aggregating approximately 19,600 miles. The natural gas distribution operations have obtained and hold, or are in the process of renewing, valid and existing franchises authorizing them to conduct their natural gas operations in all of the municipalities they serve where such franchises are required. These operations intend to protect their service areas and seek renewal of all expiring franchises. At December 31, 2017, the natural gas distribution operations' net natural gas distribution plant investment was $1.5 billion, and rate base was $975 million.
The retail customers served and respective revenues by class for the natural gas distribution operations were as follows:
 
2017
2016
2015
 
Customers
Served

Revenues

Customers
Served

Revenues

Customers
Served

Revenues

 
(Dollars in thousands)
Residential
833,255

$
477,699

818,163

$
429,828

803,846

$
455,301

Commercial
104,795

283,899

103,438

253,333

101,688

277,022

Industrial
817

24,030

807

23,337

811

26,568

 
938,867

$
785,628

922,408

$
706,498

906,345

$
758,891

Transportation and other revenues for the natural gas distribution operations were $62.8 million, $59.6 million and $58.5 million for the years ended December 31, 2017, 2016 and 2015, respectively.

 
12 MDU Resources Group, Inc. Form 10-K



Part I
 

The percentage of the natural gas distribution operations' retail sales revenues by jurisdiction was as follows:
 
2017

2016

2015

Idaho
33
%
34
%
32
%
Washington
26
%
26
%
26
%
North Dakota
13
%
13
%
15
%
Montana
9
%
8
%
8
%
Oregon
8
%
8
%
8
%
South Dakota
6
%
6
%
6
%
Minnesota
3
%
3
%
3
%
Wyoming
2
%
2
%
2
%
The natural gas distribution operations are subject to regulation by the IPUC, MNPUC, MTPSC, NDPSC, OPUC, SDPUC, WUTC and WYPSC regarding retail rates, service, accounting and certain security issuances.
System Supply, System Demand and Competition The natural gas distribution operations serve retail natural gas markets, consisting principally of residential and firm commercial space and water heating users, in portions of Idaho, including Boise, Nampa, Twin Falls, Pocatello and Idaho Falls; western Minnesota, including Fergus Falls, Marshall and Crookston; eastern Montana, including Billings, Glendive and Miles City; North Dakota, including Bismarck, Mandan, Dickinson, Wahpeton, Williston, Watford City, Minot and Jamestown; central and eastern Oregon, including Bend, Pendleton, Ontario and Baker City; western and north-central South Dakota, including Rapid City, Pierre, Spearfish and Mobridge; western, southeastern and south-central Washington, including Bellingham, Bremerton, Longview, Aberdeen, Wenatchee/Moses Lake, Mount Vernon, Tri-Cities, Walla Walla and Yakima; and northern Wyoming, including Sheridan and Lovell. These markets are highly seasonal and sales volumes depend largely on the weather, the effects of which are mitigated in certain jurisdictions by a weather normalization mechanism discussed in Regulatory Matters. In addition to the residential and commercial sales, the utilities transport natural gas for larger commercial and industrial customers who purchase their own supply of natural gas.
Competition in varying degrees exists between natural gas and other fuels and forms of energy. The natural gas distribution operations have established various natural gas transportation service rates for their distribution businesses to retain interruptible commercial and industrial loads. These services have enhanced the natural gas distribution operations' competitive posture with alternative fuels, although certain customers have bypassed the distribution systems by directly accessing transmission pipelines within close proximity. These bypasses did not have a material effect on results of operations.
The natural gas distribution operations and various distribution transportation customers obtain their system requirements directly from producers, processors and marketers. The Company's purchased natural gas is supplied by a portfolio of contracts specifying market-based pricing and is transported under transportation agreements with WBI Energy Transmission, Northern Border Pipeline Company, Northwest Pipeline LLC, South Dakota Intrastate Pipeline, TransCanada Corporation, Northern Natural Gas, Gas Transmission Northwest LLC, Northwestern Energy, Viking Gas Transmission Company, Westcoast Energy Inc., Ruby Pipeline LLC, Foothills Pipe Lines Ltd. and NOVA Gas Transmission Ltd. The natural gas distribution operations have contracts for storage services to provide gas supply during the winter heating season and to meet peak day demand with various storage providers, including WBI Energy Transmission, Questar Pipeline Company, Northwest Pipeline LLC and Northern Natural Gas. In addition, certain of the operations have entered into natural gas supply management agreements with various parties. Demand for natural gas, which is a widely traded commodity, has historically been sensitive to seasonal heating and industrial load requirements as well as changes in market price. The natural gas distribution operations believe that, based on current and projected domestic and regional supplies of natural gas and the pipeline transmission network currently available through their suppliers and pipeline service providers, supplies are adequate to meet their system natural gas requirements for the next decade.
Regulatory Matters The natural gas distribution operations' retail natural gas rate schedules contain clauses permitting adjustments in rates based upon changes in natural gas commodity, transportation and storage costs. Current tariffs allow for recovery or refunds of under- or over-recovered gas costs through rate adjustments which are filed annually.
Montana-Dakota's North Dakota and South Dakota natural gas tariffs contain weather normalization mechanisms applicable to certain firm customers that adjust the distribution delivery charge revenues to reflect weather fluctuations during the November 1 through May 1 billing periods.
In Montana, Montana-Dakota recovers in rates through a tracking mechanism the increases associated with Montana state and local taxes assessed to natural gas operations on an after tax basis.

 
MDU Resources Group, Inc. Form 10-K 13



Part I
 

On December 28, 2015, the OPUC approved an extension of Cascade's decoupling mechanism until January 1, 2020, with an agreement that Cascade would initiate a review of the mechanism by September 30, 2019. Cascade also has an earnings sharing mechanism with respect to its Oregon jurisdictional operations as required by the OPUC.
On July 7, 2016, the WUTC approved a full decoupling mechanism where Cascade is allowed recovery of an average revenue per customer regardless of actual consumption. The mechanism also includes an earnings sharing component if Cascade earns beyond its authorized return. The decoupling mechanism will be reviewed following the end of 2019.
On December 22, 2016, the MNPUC approved a request by Great Plains to implement a full revenue decoupling mechanism pilot project. The decoupling mechanism will reflect the period October 1 through September 30 with the first adjustment to be billed to customers effective December 1 each year for the 3 year pilot project.
For more information on regulatory matters, see Item 8 - Note 16.
Environmental Matters The natural gas distribution operations are subject to federal, state and local environmental, facility-siting, zoning and planning laws and regulations. The natural gas distribution operations believe it is in substantial compliance with those regulations.
The Company's natural gas distribution operations are conditionally exempt small-quantity hazardous waste generators and subject only to minimum regulation under the RCRA. Certain locations of the natural gas distribution operations routinely handle PCBs from their natural gas operations in accordance with federal requirements. PCB storage areas are registered with the EPA as required. Capital and operational expenditures for natural gas distribution operations could be affected in a variety of ways by potential new GHG legislation or regulation. In particular, such legislation or regulation would likely increase capital expenditures for energy efficiency and conservation programs and operational costs associated with GHG emissions compliance. Natural gas distribution operations expect to recover the operational and capital expenditures for GHG regulatory compliance in rates consistent with the recovery of other reasonable costs of complying with environmental laws and regulations.
The natural gas distribution operations did not incur any material environmental expenditures in 2017. Except as to what may be ultimately determined with regard to the issues described in the following paragraph, the natural gas distribution operations do not expect to incur any material capital expenditures related to environmental compliance with current laws and regulations through 2020.
Montana-Dakota and Great Plains have ties to six historic manufactured gas plants as a successor corporation or through direct ownership of the plant. Montana-Dakota is investigating one of these former manufactured gas plant sites and providing input on another site investigation conducted by a third party. To the extent not covered by insurance, Montana-Dakota may seek recovery in its natural gas rates charged to customers for certain investigation and remediation costs incurred for these sites. Cascade has ties to nine historic manufactured gas plants as a successor corporation or through direct ownership of the plant. Cascade is involved in the investigation and remediation of three of these manufactured gas plants in Washington and Oregon. See Item 8 - Note 17 for a further discussion of these three manufactured gas plants. To the extent not covered by insurance, Cascade will seek recovery of investigation and remediation costs through its natural gas rates charged to customers.
Pipeline and Midstream
General WBI Energy owns and operates both regulated and nonregulated businesses. The regulated business of this segment, WBI Energy Transmission, owns and operates approximately 4,000 miles of natural gas transmission, gathering and storage lines in Montana, North Dakota, South Dakota and Wyoming. Three underground storage fields in Montana and Wyoming provide storage services to local distribution companies, industrial customers, natural gas marketers and others, and serve to enhance system reliability. Its system is strategically located near five natural gas producing basins, making natural gas supplies available to its transportation and storage customers. The system has 13 interconnecting points with other pipeline facilities allowing for the receipt and/or delivery of natural gas to and from other regions of the country and from Canada. Under the Natural Gas Act, as amended, WBI Energy Transmission is subject to the jurisdiction of the FERC regarding certificate, rate, service and accounting matters, and at December 31, 2017, its net plant investment was $404.6 million.
The nonregulated business of this segment owns and operates gathering facilities in Montana and Wyoming. In total, facilities include approximately 800 miles of operated field gathering lines, some of which interconnect with WBI Energy's regulated pipeline system. The nonregulated business provides natural gas gathering services and a variety of other energy-related services, including cathodic protection and energy efficiency product sales and installation services to large end-users. In November 2016, the Company entered into an agreement to sell its ownership in the Pronghorn assets, which included a 50 percent undivided interest in a natural gas processing plant, both oil and gas gathering pipelines, an oil storage terminal and an oil pipeline in western North Dakota. The transaction closed in January 2017.

 
14 MDU Resources Group, Inc. Form 10-K



Part I
 

A majority of its pipeline and midstream business is transacted in the northern Great Plains and Rocky Mountain regions of the United States.
System Supply, System Demand and Competition Natural gas supplies emanate from traditional and nontraditional production activities in the region from both on-system and off-system supply sources. New incremental supply from nontraditional sources have developed, such as the Bakken area in Montana and North Dakota, which has helped offset declines in traditional regional supply sources and supports WBI Energy Transmission's transportation and storage services. In addition, off-system supply sources are available through the Company's interconnections with other pipeline systems. WBI Energy Transmission will continue to look for opportunities to increase transportation, gathering and storage services through system expansion and/or other pipeline interconnections or enhancements that could provide substantial future benefits.
WBI Energy Transmission's underground natural gas storage facilities have a certificated storage capacity of approximately 353 Bcf, including 193 Bcf of working gas capacity, 85 Bcf of cushion gas and 75 Bcf of native gas. These storage facilities enable customers to purchase natural gas throughout the year and meet winter peak requirements.
WBI Energy Transmission competes with several pipelines for its customers' transportation, storage and gathering business and at times may discount rates in an effort to retain market share. However, the strategic location of its system near five natural gas producing basins and the availability of underground storage and gathering services, along with interconnections with other pipelines, serve to enhance its competitive position.
Although certain of WBI Energy Transmission's firm customers, including its largest firm customer Montana-Dakota, serve relatively secure residential, commercial and industrial end-users, they generally all have some price-sensitive end-users that could switch to alternate fuels.
WBI Energy Transmission transports substantially all of Montana-Dakota's natural gas, primarily utilizing firm transportation agreements, which for 2017 represented 34 percent of WBI Energy Transmission's subscribed firm transportation contract demand. The majority of the firm transportation agreements with Montana-Dakota expire in June 2022. In addition, Montana-Dakota has contracts with WBI Energy Transmission to provide firm storage services to facilitate meeting Montana-Dakota's winter peak requirements expiring in July 2035.
The nonregulated business competes for existing customers in the fields in which it operates. Its focus on customer service and the variety of services it offers serve to enhance its competitive position.
Environmental Matters The pipeline and midstream operations are generally subject to federal, state and local environmental, facility-siting, zoning and planning laws and regulations. The Company believes it is in substantial compliance with those regulations.
Ongoing operations are subject to the Clean Air Act, the Clean Water Act, the RCRA and other state and federal regulations. Administration of many provisions of these laws has been delegated to the states where WBI Energy and its subsidiaries operate. Permit terms vary and all permits carry operational compliance conditions. Some permits require annual renewal, some have terms ranging from one to five years and others have no expiration date. Permits are renewed and modified, as necessary, based on defined permit expiration dates, operational demand and/or regulatory changes.
Detailed environmental assessments and/or environmental impact statements as required by the National Environmental Policy Act are included in the FERC's environmental review process for both the construction and abandonment of WBI Energy Transmission's natural gas transmission pipelines, compressor stations and storage facilities.
The pipeline and midstream operations did not incur any material environmental expenditures in 2017 and do not expect to incur any material capital expenditures related to environmental compliance with current laws and regulations through 2020.
Construction Materials and Contracting
General Knife River operates construction materials and contracting businesses headquartered in Alaska, California, Hawaii, Idaho, Iowa, Minnesota, Montana, North Dakota, Oregon, Texas, Washington and Wyoming. These operations mine, process and sell construction aggregates (crushed stone, sand and gravel); produce and sell asphalt mix; and supply ready-mixed concrete. These products are used in most types of construction, performed by Knife River and other companies, including roads, freeways and bridges, as well as homes, schools, shopping centers, office buildings and industrial parks. Knife River focuses on vertical integration of construction services to support the aggregate based product lines including aggregate placement, asphalt and concrete paving, and site development and grading. Although not common to all locations, other products include the sale of cement, liquid asphalt for various commercial and roadway applications, various finished concrete products and other building materials and related contracting services.

 
MDU Resources Group, Inc. Form 10-K 15



Part I
 

Knife River's backlog was approximately $486 million, $538 million and $491 million at December 31, 2017, 2016 and 2015, respectively. The decrease in backlog at December 31, 2017, compared to backlog at December 31, 2016, was primarily attributable to a lower backlog of state agency work. Backlog increases with awards of new contracts and decreases as work is performed on existing contracts. Knife River expects to complete a significant amount of the backlog at December 31, 2017, during the next 12 months.
Knife River's backlog is comprised of the anticipated revenues from the uncompleted portion of services to be performed under job-specific contracts. A project is included in backlog when a contract is awarded and agreement on contract terms has been reached. However, backlog does not contain contracts for time and material projects that a fixed amount cannot be determined. Backlog is comprised of: (a) original contract amounts, (b) change orders for which customers have approved and (c) claim amounts that have been made against customers for which are determined to have a legal basis under existing contractual arrangements and as to which recovery is considered to be probable. Such claim amounts were immaterial for all periods presented. Backlog may be subject to delay, default or cancellation at the election of the customers. Historically, cancellations have not had a materially adverse effect on backlog. Due to the nature of its contractual arrangements, in many instances Knife River's customers are not committed to the specific volumes of services to be purchased under a contract, but rather Knife River is committed to perform these services if and to the extent requested by the customer. Therefore, there can be no assurance as to the customers' requirements during a particular period or that such estimates at any point in time are predictive of future revenues.
Competition Knife River's construction materials products and contracting services are marketed under highly competitive conditions. Price is the principal competitive force to which these products and services are subject, with service, quality, delivery time and proximity to the customer also being significant factors. Knife River focuses on markets located near aggregate sites to reduce transportation costs which allows Knife River to remain competitive with the pricing of aggregate products. The number and size of competitors varies in each of Knife River's principal market areas and product lines.
The demand for construction materials products and contracting services is significantly influenced by the cyclical nature of the construction industry in general. In addition, construction materials and contracting services activity in certain locations may be seasonal in nature due to the effects of weather. The key economic factors affecting product demand are changes in the level of local, state and federal governmental spending on roads and infrastructure projects, general economic conditions within the market area that influence both the commercial and residential sectors, and prevailing interest rates.
Knife River's customers are a diverse group which includes federal, state and municipal government agencies, commercial and residential developers, and private parties. The mix of sales by customer will vary each year depending on the work available. Knife River is not dependent on any single customer or group of customers for sales of its products and services, the loss of which would have a material adverse effect on its construction materials businesses.
Reserve Information Aggregate reserve estimates are calculated based on the best available data. This data is collected from drill holes and other subsurface investigations, as well as investigations of surface features such as mine high walls and other exposures of the aggregate reserves. Mine plans, production history and geologic data also are utilized to estimate reserve quantities.
Estimates are based on analyses of the data described above by experienced internal mining engineers, operating personnel and geologists. Property setbacks and other regulatory restrictions and limitations are identified to determine the total area available for mining. Data described previously are used to calculate the thickness of aggregate materials to be recovered. Topography associated with alluvial sand and gravel deposits is typically flat and volumes of these materials are calculated by applying the thickness of the resource over the areas available for mining. Volumes are then converted to tons by using an appropriate conversion factor. Typically, 1.5 tons per cubic yard in the ground is used for sand and gravel deposits.
Topography associated with the hard rock reserves is typically much more diverse. Therefore, using available data, a final topography map is created and computer software is utilized to compute the volumes between the existing and final topographies. Volumes are then converted to tons by using an appropriate conversion factor. Typically, 2 tons per cubic yard in the ground is used for hard rock quarries.
Estimated reserves are probable reserves as defined in Securities Act Industry Guide 7. Remaining reserves are based on estimates of volumes that can be economically extracted and sold to meet current market and product applications. The reserve estimates include only salable tonnage and thus exclude waste materials that are generated in the crushing and processing phases of the operation. Approximately 891 million tons of the 965 million tons of aggregate reserves are permitted reserves. The remaining reserves are on properties that are expected to be permitted for mining under current regulatory requirements. The data used to calculate the remaining reserves may require revisions in the future to account for changes in customer requirements and unknown geological occurrences. The years remaining were calculated by dividing remaining reserves by the three-year average sales from 2015 through 2017. Actual useful lives of these reserves will be subject to, among other things, fluctuations in customer demand, customer specifications, geological conditions and changes in mining plans.

 
16 MDU Resources Group, Inc. Form 10-K



Part I
 

The following table sets forth details applicable to the Company's aggregate reserves under ownership or lease as of December 31, 2017, and sales for the years ended December 31, 2017, 2016 and 2015:
 
Number of Sites
(Crushed Stone)
 
Number of Sites
(Sand & Gravel)
 
Tons Sold (000's)
Estimated Reserves
(000's tons)

Lease Expiration
Reserve
Life
(years)

Production Area
owned

leased

 
owned

leased

 
2017

2016

2015

Anchorage, AK


 
1


 
1,425

1,343

1,837

14,548

N/A
9

Hawaii

5

 


 
1,614

1,901

1,892

50,659

2018-2064
28

Northern CA


 
9

1

 
1,785

1,604

1,580

43,812

2018
26

Southern CA

2

 


 
55

224

118

91,567

2035
Over 100

Portland, OR
1

3

 
5

3

 
4,694

4,044

3,562

213,018

2025-2057
52

Eugene, OR
3

4

 
6


 
633

662

819

153,975

2021-2049
Over 100

Central OR/WA/ID

1

 
5

2

 
2,160

1,685

1,493

86,307

2020-2087
49

Southwest OR
5

5

 
10

6

 
2,367

2,689

1,872

100,875

2019-2053
44