UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 10-K

Annual Report
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

For the fiscal year ended December 31, 2010

Commission file number: 333-107569-03

Arch Western Resources, LLC

(Exact name of registrant as specified in its charter)


Delaware (State or other jurisdiction of incorporation or organization)		43-1811130 (I.R.S. Employer Identification Number)

One CityPlace Drive, Ste. 300, St. Louis, Missouri (Address of principal executive offices)		63141 (Zip code)

Registrant’s telephone number, including area code: (314) 994-2700

Securities registered pursuant to Section 12(b) of the Act: None

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 o No þ

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes þ No o

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 o No þ

(Note: As a voluntary filer not subject to the filing requirements of Section 13 or 15(d) of the Exchange Act, the registrant has filed all reports pursuant to Section 13 or 15(d) of the Exchange Act during the preceding 12 months as if it were subject to such filing requirements.)

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Date 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 o 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 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. o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definition of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):


Large Accelerated Filer o	Accelerated Filer o	Non-Accelerated Filer þ	Smaller Reporting Company o
		(Do not check if a smaller reporting company)

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o No þ

At March 28, 2011, the registrant’s common equity consisted solely of undenominated membership interests, 99.5% of which were held by Arch Western Acquisition Corporation and 0.5% of which were held by a subsidiary of BP p.l.c.

TABLE OF CONTENTS


	Page
PART I
ITEM 1. BUSINESS		3
ITEM 1A. RISK FACTORS		22
ITEM 1B. UNRESOLVED STAFF COMMENTS		29
ITEM 2. PROPERTIES		29
ITEM 3. LEGAL PROCEEDINGS		32
ITEM 4. RESERVED		32
PART II
ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES		34
ITEM 6. SELECTED FINANCIAL DATA		35
ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS		35
ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK		45
ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA		45
ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE		45
ITEM 9A. CONTROLS AND PROCEDURES		45
ITEM 9B. OTHER INFORMATION		46
PART III
ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE		46
ITEM 11. EXECUTIVE COMPENSATION		47
ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS		47
ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE		48
ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES		48
PART IV
ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES		48
EX-21.1
EX-31.1
EX-31.2
EX-32.1
EX-32.2

If you are not familiar with any of the mining terms used in this report, we have provided explanations of many of them under the caption “Glossary of Selected Mining Terms” on page 21 of this report. Unless the context otherwise requires, all references in this report to “Arch Western,” “we,” “us,” or “our” are to Arch Western Resources, LLC and its subsidiaries.

CAUTIONARY STATEMENTS REGARDING FORWARD-LOOKING INFORMATION

This report contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, such as our expected future business and financial performance, and are intended to come within the safe harbor protections provided by those sections. The words “anticipates,” “believes,” “could,” “estimates,” “expects,” “intends,” “may,” “plans,” “predicts,” “projects,” “seeks,” “should,” “will” or other comparable words and phrases identify forward-looking statements, which speak only as of the date of this report. Forward-looking statements by their nature address matters that are, to different degrees, uncertain. Actual results may vary significantly from those anticipated due to many factors, including:

	•		market demand for coal and electricity;

	•		geologic conditions, weather and other inherent risks of coal mining that are beyond our control;

	•		competition within our industry and with producers of competing energy sources;

	•		excess production and production capacity;

	•		our ability to acquire or develop coal reserves in an economically feasible manner;

	•		inaccuracies in our estimates of our coal reserves;

	•		availability and price of mining and other industrial supplies;

	•		availability of skilled employees and other workforce factors;

	•		our ability to collect payments from our customers;

	•		defects in title or the loss of a leasehold interest;

	•		railroad, barge, truck and other transportation performance and costs;

	•		our ability to successfully integrate the operations that we acquire;

	•		our ability to secure new coal supply arrangements or to renew existing coal supply arrangements;

	•		our relationships with, and other conditions affecting, our customers;

	•		the deferral of contracted shipments of coal by our customers;

	•		our ability to service our outstanding indebtedness;

	•		our ability to comply with the restrictions imposed by our financing arrangements;

	•		the availability and cost of surety bonds;

	•		terrorist attacks, military action or war;

	•		our ability to obtain and renew various permits, including permits authorizing the disposition of certain mining waste;

	•		existing and future legislation and regulations affecting both our coal mining operations and our customers’ coal usage, governmental policies and taxes, including those aimed at reducing emissions of elements such as mercury, sulfur dioxides, nitrogen oxides, particulate matter or greenhouse gases;

	•		the accuracy of our estimates of reclamation and other mine closure obligations;

	•		the existence of hazardous substances or other environmental contamination on property owned or used by us; and

	•		the other factors affecting our business described below under the caption “Risk Factors.”

All forward-looking statements in this report, as well as all other written and oral forward-looking statements attributable to us or persons acting on our behalf, are expressly qualified in their entirety by the cautionary statements contained in this section and elsewhere in this report. See Items 1A “Risk Factors,” 7 “Management’s Discussion and Analysis of Financial Condition and Results of Operations” and 7A “Quantitative and Qualitative Disclosures About Market Risk” for additional information about

factors that may affect our businesses and operating results. These factors are not necessarily all of the important factors that could affect us. These risks and uncertainties, as well as other risks of which we are not aware or which we currently do not believe to be material, may cause our actual future results to be materially different than those expressed in our forward-looking statements. We do not undertake to update our forward-looking statements, whether as a result of new information, future events or otherwise, except as may be required by law.

PART I


ITEM 1.		BUSINESS.

Introduction

We are a subsidiary of Arch Coal, Inc., one of the world’s largest coal producers. For the year ended December 31, 2010, we sold approximately 144 million tons of coal, representing roughly 13% of the U.S. coal supply. We sell substantially all of our coal to power plants and industrial facilities. At December 31, 2010, we operated seven active mines located in two of the three major low-sulfur coal-producing regions of the United States.

Significant federal and state environmental regulations affect the demand for coal. Existing environmental regulations limiting the emission of certain impurities caused by coal combustion and new regulations have had and are likely to continue to have a considerable impact on our business. For example, certain federal and state environmental regulations currently limit the amount of sulfur dioxide that may be emitted as a result of combustion. As a result, we focus on mining, processing and marketing coal with low sulfur content.

Despite these and other regulations, we expect worldwide coal demand to increase over time, particularly in developing countries such as China and India, where electricity demand is increasing much faster than in developed parts of the world. Although the global economic recession has had a significant impact on certain regions of the world, we expect worldwide energy demand to increase over the next 20 years.

Our History

We were formed as a joint venture on June 1, 1998 when Arch Coal acquired certain coal assets of Atlantic Richfield Company and combined those operations with Arch Coal’s existing western operations and Atlantic Richfield’s remaining Wyoming operations.

On August 20, 2004, Arch Coal acquired Vulcan Coal Holdings, L.L.C., which owned all of the common equity of Triton Coal Company, LLC, and all of the preferred units of Triton for a purchase price of $382.1 million, including transaction costs and working capital adjustments. Following the acquisition, Arch Coal contributed the assets and liabilities of Triton’s North Rochelle mine (excluding coal reserves) to us. Following that contribution, we integrated the operations of the North Rochelle mine with our existing Black Thunder mine in the Powder River Basin.

On October 1, 2009, Arch Coal acquired the Jacobs Ranch mining operations for a purchase price of $768.8 million including transaction costs and working capital adjustments. The acquisition included approximately 345 million tons of coal reserves located adjacent to our Black Thunder mining complex. Arch Coal contributed the acquired assets and liabilities (excluding coal reserves) to us, which we immediately merged with our Black Thunder mining operations. We lease the Jacobs Ranch coal reserves from a subsidiary of Arch Coal.

Coal Characteristics

In general, end users characterize coal as steam coal or metallurgical coal. Heat value, sulfur, ash, moisture content, and volatility in the case of metallurgical coal, are important variables in the marketing and transportation of coal. These characteristics help producers determine the best end use of a particular type of coal. The following is a description of these general coal characteristics:

Heat Value. In general, the carbon content of coal supplies most of its heating value, but other factors also influence the amount of energy it contains per unit of weight. The heat value of coal is commonly measured in Btus. Coal is generally classified into four categories, ranging from lignite, subbituminous, bituminous and anthracite, reflecting the progressive response of individual deposits of coal to increasing heat and pressure. Anthracite is coal with the highest carbon content and, therefore, the highest heat value, nearing 15,000 Btus per pound. Bituminous coal, used primarily to generate electricity and to make coke for the steel industry, has a heat value ranging between 10,500 and 15,500 Btus per pound. Subbituminous coal ranges from 8,300 to 13,000

Btus per pound and is generally used for electric power generation. Lignite coal is a geologically young coal which has the lowest carbon content and a heat value ranging between 4,000 and 8,300 Btus per pound.

Sulfur Content. Federal and state environmental regulations, including regulations that limit the amount of sulfur dioxide that may be emitted as a result of combustion, have affected and may continue to affect the demand for certain types of coal. The sulfur content of coal can vary from seam to seam and within a single seam. The chemical composition and concentration of sulfur in coal affects the amount of sulfur dioxide produced in combustion. Coal-fueled power plants can comply with sulfur dioxide emission regulations by burning coal with low sulfur content, blending coals with various sulfur contents, purchasing emission allowances on the open market and/or using sulfur-dioxide emission reduction technology.

All of our identified coal reserves have been subject to preliminary coal seam analysis to test sulfur content. Of these reserves, approximately 93.5% consist of compliance coal, while an additional 3.2% could be sold as low-sulfur coal. The balance is classified as high-sulfur coal. Higher sulfur coal can be burned in plants equipped with sulfur-dioxide emission reduction technology, such as scrubbers, and in facilities that blend compliance and noncompliance coal.

Ash. Ash is the inorganic residue remaining after the combustion of coal. As with sulfur, ash content varies from seam to seam. Ash content is an important characteristic of coal because it impacts boiler performance and electric generating plants must handle and dispose of ash following combustion. The composition of the ash, including the proportion of sodium oxide and fusion temperature, are important characteristics of coal and help determine the suitability of the coal to end users. The absence of ash is also important to the process by which metallurgical coal is transformed into coke for use in steel production.

Moisture. Moisture content of coal varies by the type of coal, the region where it is mined and the location of the coal within a seam. In general, high moisture content decreases the heat value and increases the weight of the coal, thereby making it more expensive to transport. Moisture content in coal, on an as-sold basis, can range from approximately 2% to over 30% of the coal’s weight.

The Coal Industry

Global Coal Supply and Demand. Recovery from the 2008 upheaval in the global financial markets continued in 2010. Growth rates varied in 2010 in both emerging market economies and advanced market economies, as countries worked to rebalance their reliance on domestic consumption against export demand growth. Recovering international coal demand led to a substantial rise in the global demand for coal from the United States during 2010.

Coal is traded globally and can be transported to demand centers by ship, rail, barge, and truck. Worldwide coal production approximated 6.9 billion tonnes in 2009, up from 6.7 billion tonnes in 2008, according to the International Energy Agency (IEA). China remains the largest producer of coal in the world, producing over 2.97 billion tonnes in 2009, according to the IEA. China is followed in coal production by the USA at approximately 919 million tonnes and India at nearly 526 million tonnes. China’s coal exports have dwindled to approximately 20 million tonnes per year and imports have increased to over 160 million tones per year in 2010 as domestic demands exceed domestic supply. Japan maintained its ranking as the top importer of coal with 183 million tonnes in 2009, followed by China and South Korea at 118 million tonnes.

International demand for coal continues to be driven by growth in electrical power generation. Coal remains the leading fuel for power generation in the IEA’s World Energy Outlook scenarios. Coal’s share of global electricity generation remains between 41% and 43% through 2035 in the Current Policies Scenario. Growth is most significant in non-OECD countries where electricity from coal grows from approximately 46% of total electricity generation in 2008 to approximately 50% in 2035. China is the world’s largest consumer of coal, and China and India together account for 72% of the new coal-fired generation currently under construction and expected to come online in the next five years.

Metallurgical or coking coal is used in the steel making process. The steel industry uses metallurgical coal, which is distinguishable from other types of coal by its high carbon content, low expansion pressure, low sulfur content and various other chemical attributes. As such, the price offered by steel makers for metallurgical coal is generally higher than the price offered by power plants and industrial users for steam coal. Coal is used in nearly 70% of global steel production. In 2010, approximately 1.395 billion tonnes of steel was produced, which represented a recovery of 15% over 2009 reduced levels.

Supplying the global power and steel markets are Australia, historically the world’s largest coal exporter with exports of approximately 300 million tonnes in 2010, as well as Indonesia, Russia, United States, Colombia, and South Africa. Indonesia, in particular, has seen substantial growth in its coal exports in the last few years; however, its growing domestic energy demand may result in a decrease in exports as it moves toward greater self-sufficiency. Total U.S. exports were 81 million tonnes in 2010. As global economic conditions continue to improve and growth accelerates, putting pressure on global coal supply networks, we expect the demand for U.S. coal exports to continue to grow.

U.S. Coal Consumption. In the United States, coal is used primarily by power plants to generate electricity, by steel companies to produce coke for use in blast furnaces and by a variety of industrial users to heat and power foundries, cement plants, paper mills, chemical plants and other manufacturing or processing facilities. Coal consumption in the United States increased from 398.1 million tons in 1960 to approximately 1.0 billion tons in 2010, according to the Energy Information Administration’s (EIA) Short Term Energy Outlook. Although full-year data for 2010 is not yet available, coal consumption has improved over what was lost during the global downturn that affected U.S. coal consumption in 2009. In 2010, coal consumption in the United States improved through stronger electricity demand driven by both a recovering economy and favorable weather.

The following chart shows historical and projected demand trends for U.S. coal by consuming sector for the periods indicated, according to the EIA:


	Actual		Estimated		Forecast						Annual Growth
Sector	2005		2010		2011		2020		2035		2009-2035
					(Tons, in millions)
Electric power		1,037		977		950		986		1,129		0.7	%
Other industrial		60		47		48		49		47		0.1	%
Coke plants		23		21		22		22		18		0.6	%
Residential/commercial		4		3		3		3		3		-0.2	%
Coal-to-liquids		—		—		—		16		105		n/a

Total U.S. coal consumption		1,126		1,048		1,022		1,076		1,302		1.0	%


Source: EIA Annual Energy Outlook 2011

		EIA Short Term Energy Outlook (January 2011)

		EIA Monthly Energy Review (December 2010)

According to the EIA, coal accounted for approximately 45% of U.S. electricity generation in 2010, and based on a projected 25% growth in electricity demand, coal consumption is expected to grow about 19% by 2035, reaching 1.1 billion tons. These amounts assume no future federal or state carbon emissions legislation is enacted and do not take into account subsequent market conditions. Historically, coal has been considerably less expensive than natural gas or oil.

The following chart shows the breakdown of U.S. electricity generation by energy source for 2010, according to the EIA:


		Source: EIA Monthly Flash Estimate of Electric Power Data (January 2011).

Average prices for oil in the United States increased during 2010 following the effects of the worldwide economic recession. Historically, volatile oil prices and global energy security concerns have increased interest in converting coal into liquid fuel, a process known as liquefaction. Liquid fuel produced from coal can be further refined to produce transportation fuels, such as low-sulfur diesel fuel, gasoline and other oil products, such as plastics and solvents. Currently, there are only a limited number of projects moving forward because of lower oil and natural gas prices.

U.S. Coal Production. The United States is the second largest coal producer in the world, exceeded only by China. According to the EIA, there are over 200 billion tons of recoverable coal in the United States. The U.S. Department of Energy estimates that current domestic recoverable coal reserves could supply enough electricity to satisfy domestic demand for approximately

200 years. Annual coal production in the United States has increased from 434 million tons in 1960 to approximately 1.1 billion tons in 2010.

Coal is mined from coal fields throughout the United States, with the major production centers located in the western United States, the Appalachian region and the Illinois Basin.

Major regions in the West include the Powder River Basin and the Western Bituminous region. According to the EIA, coal produced in the western United States increased from 408 million tons in 1994 to an estimated 636 million tons in 2010, as competitive mining costs and regulations limiting sulfur-dioxide emissions have continued to increase demand for low-sulfur coal over this period. The Powder River Basin is located in northeastern Wyoming and southeastern Montana. Coal from this region is sub-bituminous coal with low sulfur content ranging from 0.2% to 0.9% and heating values ranging from 8,000 to 9,500 Btu. The price of Powder River Basin coal is generally less than that of coal produced in other regions because Powder River Basin coal exists in greater abundance, is easier to mine and thus has a lower cost of production. In addition, Powder River Basin coal is generally lower in heat value, which requires some electric power generation facilities to blend it with higher Btu coal or retrofit some existing coal plants to accommodate lower Btu coal. The Western Bituminous region includes Colorado, Utah and southern Wyoming. Coal from this region typically has low sulfur content ranging from 0.4% to 0.8% and heating values ranging from 10,000 to 12,200 Btu.

Regions in the East include the north, central and southern Appalachian regions. According to the EIA, coal produced in the Appalachian region decreased from 445 million tons in 1994 to an estimated 338 million tons in 2010 primarily as a result of the depletion of economically attractive reserves, permitting issues and increasing costs of production. Central Appalachia includes eastern Kentucky, Tennessee, Virginia and southern West Virginia. Coal mined from this region generally has a high heat value ranging from 11,400 to 13,200 Btu and a low sulfur content ranging from 0.2% to 2.0%. Northern Appalachia includes Maryland, Ohio, Pennsylvania and northern West Virginia. Coal from this region generally has a high heat value ranging from 10,300 to 13,500 Btu and a high sulfur content ranging from 0.8% to 4.0%. Southern Appalachia primarily covers Alabama and generally has a heat content ranging from 11,300 to 12,300 Btu and a sulfur content ranging from 0.7% to 3.0%.

The Illinois Basin includes Illinois, Indiana and western Kentucky and is the major coal production center in the interior region of the United States. According to the EIA, coal produced in the interior region decreased from 180 million tons in 1994 to approximately 105 million tons in 2010. Coal from the Illinois Basin generally has a heat value ranging from 10,100 to 12,600 Btu and has a high sulfur content ranging from 1.0% to 4.3%. Despite its high sulfur content, coal from the Illinois basin can generally be used by some electric power generation facilities that have installed pollution control devices, such as scrubbers, to reduce emissions. Other coal-producing states in the interior include Arkansas, Kansas, Louisiana, Mississippi, Missouri, North Dakota, Oklahoma and Texas.

U.S. Coal Exports and Imports. U.S exports increased substantially over 2009, supported by recovering global economies and continued growth in Chinese and Indian steel markets in particular. This is a trend we expect to continue. Because of this, we believe that the United States will continue to be an increasingly important supplier of coal to the global marketplace in the near term.

Historically, coal imported from abroad has represented a relatively small share of total U.S. coal consumption, and this remained the case in 2010. According to the EIA, coal imports increased from 9 million tons in 1994 to an estimated 19 million tons in 2010. Imports did reach close to 36 million tons in 2007, but have fallen since then. The decline is mostly attributed to more competitive pricing for domestic coal and stronger demand from non-U.S. markets for seaborne coal. Coal is imported into the United States primarily from Colombia, Indonesia and Venezuela. Imported coal generally serves coastal states along the Gulf of Mexico, such as Alabama and Florida, and states along the eastern seaboard. We do not expect imports to be significant in 2011 and beyond, as more and more global coal will likely be directed to Asia.

Coal Mining Methods

The geological characteristics of our coal reserves largely determine the coal mining method we employ. We use two primary methods of mining coal: surface mining and underground mining.

Surface Mining. We use surface mining when coal is found close to the surface. We have included the identity and location of our surface mining operations below under “Our Mining Operations — General.” In 2010, approximately 89% of the coal that we produced came from surface mining operations.

Surface mining involves removing the topsoil then drilling and blasting the overburden (earth and rock covering the coal) with explosives. We then remove the overburden with heavy earth-moving equipment, such as draglines, power shovels, excavators and loaders. Once exposed, we drill, fracture and systematically remove the coal using haul trucks or conveyors to transport the coal to

a preparation plant or to a loadout facility. We reclaim disturbed areas as part of our normal mining activities. After final coal removal, we use draglines, power shovels, excavators or loaders to backfill the remaining pits with the overburden removed at the beginning of the process. Once we have replaced the overburden and topsoil, we reestablish vegetation and plant life into the natural habitat and make other improvements that have local community and environmental benefits.

The following diagram illustrates a typical dragline surface mining operation:

Underground Mining. We use underground mining methods when coal is located deep beneath the surface. We have included the identity and location of our underground mining operations in the table “Our Mining Operations — General.” In 2010, approximately 11% of the coal that we produced came from underground mining operations.

Our underground mines are typically operated using longwall mining techniques. Longwall mining involves using mechanical shearer to extract coal from long rectangular blocks of medium to thick seams. Ultimate seam recovery using longwall mining techniques can exceed 75%. In longwall mining, we use continuous miners to develop access to these long rectangular coal blocks. Hydraulically powered supports temporarily hold up the roof of the mine while a rotating drum mechanically advances across the face of the coal seam, cutting the coal from the face. Chain conveyors then move the loosened coal to an underground mine conveyor system for delivery to the surface. Once coal is extracted from an area, the roof is allowed to collapse in a controlled fashion.

The following diagram illustrates a typical underground mining operation using longwall mining techniques:

Coal Preparation and Blending. We crush the coal mined from our Powder River Basin mining complexes and ship it directly from our mines to the customer. Typically, no additional preparation is required for a saleable product. Coal extracted from some of our underground mining operations contains impurities, such as rock, shale and clay, and occurs in a wide range of particle sizes. A few of our mines in the Western Bituminous region use a coal preparation plant located near the mine or connected to the mine by a conveyor. These coal preparation plants allow us to treat the coal we extract from those mines to ensure a consistent quality and to enhance its suitability for particular end-users.

The treatments we employ at our preparation plants depend on the size of the raw coal. For course material, the separation process relies on the difference in the density between coal and waste rock where, for the very fine fractions, the separation process relies on the difference in surface chemical properties between coal and the waste minerals. To remove impurities, we crush raw coal and classify it into various sizes. For the largest size fractions, we use dense media vessel separation techniques in which we float coal in a tank containing a liquid of a pre-determined specific gravity. Since coal is lighter than its impurities, it floats, and we can separate it from rock and shale. We treat intermediate sized particles with dense medium cyclones, in which a liquid is spun at high speeds to separate coal from rock. Fine coal is treated in spirals, in which the differences in density between coal and rock allow them, when suspended in water, to be separated. Ultra fine coal is recovered in column flotation cells utilizing the differences in surface chemistry between coal and rock. By injecting stable air bubbles through a suspension of ultra fine coal and rock, the coal particles adhere to the bubbles and rise to the surface of the column where they are removed. To minimize the moisture content in coal, we process most coal sizes through centrifuges. A centrifuge spins coal very quickly, causing water accompanying the coal to separate.

For more information about the preparation plants used at our mining operations, you should see the section entitled “Our Mining Operations” below.

OUR MINING OPERATIONS

General

At December 31, 2010, we operated seven active mines at seven mining complexes located in the United States. We have two reportable business segments, which are based on the low-sulfur coal producing regions in the United States in which we operate — the Powder River Basin and the Western Bituminous region. These geographically distinct areas are characterized by geology, coal transportation routes to consumers, regulatory environments and coal quality. These regional similarities have caused market and contract pricing environments to develop by coal region and form the basis for the segmentation of our operations. We incorporate by reference the information about the operating results of each of our segments for the years ended December 31, 2010, 2009 and 2008 contained in Note 15 — Segment Information to our consolidated financial statements beginning on page F-16.

Our operations in the Powder River Basin are located in Wyoming and include two surface mining complexes (Black Thunder and Coal Creek). Our operations in the Western Bituminous region are located in southern Wyoming, Colorado and Utah and

include four underground mining complexes (Dugout Canyon, Skyline, Sufco and West Elk) and one surface mining complex (Arch of Wyoming).

In general, we have developed our mining complexes and preparation plants at strategic locations in close proximity to rail facilities. Coal is transported from our mining complexes to customers by means of railroads, trucks, barge lines, and ocean-going vessels from terminal facilities. We currently own or lease under long-term arrangements a substantial portion of the equipment utilized in our mining operations. We employ sophisticated preventative maintenance and rebuild programs and upgrade our equipment to ensure that it is productive, well-maintained and cost-competitive. Our maintenance programs also employ procedures designed to enhance the efficiencies of our operations.

The following map shows the locations of our mining operations:

The following table provides a summary of information regarding our active mining complexes at December 31, 2010, the total sales associated with these complexes for the years ended December 31, 2008, 2009 and 2010 and the total reserves associated with these complexes at December 31, 2010. The amount disclosed below for the total cost of property, plant and equipment of each mining complex does not include the costs of the coal reserves that we have assigned to an individual complex. The information included below in the following table describes in more detail our mining operations, the coal mining methods used, certain characteristics of our coal and the method by which we transport coal from our mining operations to our customers or other third parties.

Total Cost

of Property,

Plant and

Equipment

Mining

Tons Sold

at December 31,

Assigned

Mining Complex

Mines

Equipment

Railroad

2008

2009

2010

Reserves

(Million tons)

($ in millions)

(Million tons)

Powder River Basin:

Black Thunder

D, S

UP/BN

88.5

81.2

116.2

1,039.2

1,405.7

Coal Creek

D, S

UP/BN

11.5

9.8

11.4

149.0

184.8

Western Bituminous:

Arch of Wyoming

0.2

0.1

22.8

14.8

Dugout Canyon

LW, CM

4.3

3.2

2.3

138.4

10.8

Total Cost

of Property,

Plant and

Equipment

Mining

Tons Sold

at December 31,

Assigned

Mining Complex

Mines

Equipment

Railroad

2008

2009

2010

Reserves

(Million tons)

($ in millions)

(Million tons)

Skyline

LW, CM

3.3

2.8

2.9

164.3

17.1

Sufco

LW, CM

7.4

6.6

6.1

225.3

56.5

West Elk

LW, CM

5.3

4.0

4.8

466.9

63.7

Totals

120.5

107.7

143.8

2,205.9

1,753.4


S	= Surface mine
U	= Underground mine
D	= Dragline
L	= Loader/truck
S	= Shovel/truck
LW	= Longwall
CM	= Continuous miner
UP	= Union Pacific Railroad
BN	= Burlington Northern Santa Fe Railway

Powder River Basin

Black Thunder. Black Thunder is a surface mining complex located on approximately 33,800 acres in Campbell County, Wyoming. The Black Thunder mining complex extracts steam coal from the Upper Wyodak and Main Wyodak seams. The Black Thunder mining complex shipped 116.2 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal and state leases. The Black Thunder mining complex had approximately 1,405.7 million tons of proven and probable reserves at December 31, 2010. The air quality permit for the Black Thunder mine allows for the mining of coal at a rate of 190.0 million tons per year. Without the addition of more coal reserves, the current reserves could sustain current production levels until 2021 before annual output starts to significantly decline, although in practice production would drop in phases extending the ultimate mine life. Several large tracts of coal adjacent to the Black Thunder mining complex have been nominated for lease, and other potential large areas of unleased coal remain available for nomination by us or other mining operations. The U.S. Department of Interior Bureau of Land Management, which we refer to as the BLM, will determine if the tracts will be leased and, if so, the final boundaries of, and the coal tonnage for, these tracts.

The Black Thunder mining complex currently consists of seven active pit areas and three loadout facilities. We ship all of the coal raw to our customers via the Burlington Northern-Santa Fe and Union Pacific railroads. We do not process the coal mined at this complex. Each of the loadout facilities can load a 15,000-ton train in less than two hours.

Coal Creek. Coal Creek is a surface mining complex located on approximately 7,400 acres in Campbell County, Wyoming. The Coal Creek mining complex extracts steam coal from the Wyodak-R1 and Wyodak-R3 seams. The Coal Creek mining complex shipped 11.4 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal and state leases. The Coal Creek mining complex had approximately 184.8 million tons of proven and probable reserves at December 31, 2010. The air quality permit for the Coal Creek mine allows for the mining of coal at a rate of 50.0 million tons per year. Without the addition of more coal reserves, the current reserves will sustain current production levels until 2025 before annual output starts to significantly decline. One tract of coal adjacent to the Coal Creek mining complex has been nominated for lease, and other potential areas of unleased coal remain available for nomination by us or other mining operations. The BLM will determine if these tracts will be leased and, if so, the final boundaries of, and the coal tonnage for, these tracts.

The Coal Creek complex currently consists of two active pit areas and a loadout facility. We ship all of the coal raw to our customers via the Burlington Northern-Santa Fe and Union Pacific railroads. We do not process the coal mined at this complex. The loadout facility can load a 15,000-ton train in less than three hours.

Western Bituminous

Arch of Wyoming. Arch of Wyoming is a surface mining complex located in Carbon County, Wyoming. The Arch of Wyoming complex currently consists of one active surface mine and four inactive mines located on approximately 58,000 acres that are in the final process of reclamation and bond release. The Arch of Wyoming mining complex extracts coal from the Johnson seam. The Arch of Wyoming complex shipped 0.1 million tons of coal in 2010.

We control a significant portion of the coal reserves associated with this complex through federal, state and private leases. The active Arch of Wyoming mining operations had approximately 14.8 million tons of proven and probable reserves at December 31, 2010. The air quality permit for the active Arch of Wyoming mining operation allows for the mining of coal at a rate of 2.5 million

tons per year. Without the addition of more coal reserves, the current reserves will sustain current production levels until 2018 before annual output starts to significantly decline.

The active Arch of Wyoming mining operations currently consist of one active pit area. We ship all of the coal raw to our customers via the Union Pacific railroad and by truck. We do not process the coal mined at this complex.

Dugout Canyon. Dugout Canyon mine is an underground mining complex located on approximately 18,572 acres in Carbon County, Utah. The Dugout Canyon mining complex has extracted steam coal from the Rock Canyon and Gilson seams. The Dugout Canyon mining complex shipped 2.3 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal and state leases. The Dugout Canyon mining complex had approximately 10.8 million tons of proven and probable reserves at December 31, 2010. The coal seam currently being mined will sustain current production levels until approximately mid-2012, at which point we will need to transition to another coal seam to continue mining.

The complex currently consists of a longwall, three continuous miner sections and a truck loadout facility. We ship all of the coal to our customers via the Union Pacific railroad or by highway trucks. We wash a portion of the coal we produce at a 400-ton-per-hour preparation plant. The loadout facility can load approximately 20,000 tons of coal per day into highway trucks. Coal shipped by rail is loaded through a third-party facility capable of loading an 11,000-ton train in less than three hours.

Skyline. Skyline is an underground mining complex located on approximately 13,230 acres in Carbon and Emery Counties, Utah. The Skyline mining complex extracts steam coal from the Lower O’Conner A seam. The Skyline mining complex shipped 2.9 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal leases and smaller portions through county and private leases. The Skyline mining complex had approximately 17.1 million tons of proven and probable reserves at December 31, 2010. The reserve area currently being mined will sustain current production levels through 2012, at which point we plan to transition to a new reserve area in order to continue mining.

The Skyline complex currently consists of a longwall, two continuous miner sections and a loadout facility. We ship most of the coal raw to our customers via the Union Pacific railroad or by highway trucks. We process a portion of the coal mined at this complex at a nearby preparation plant. The loadout facility can load a 12,000-ton train in less than four hours.

Sufco. Sufco is an underground mining complex located on approximately 27,550 acres in Sevier County, Utah. The Sufco mining complex extracts steam coal from the Upper Hiawatha seam. The Sufco mining complex shipped 6.1 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal and state leases. The Sufco mining complex had approximately 56.5 million tons of proven and probable reserves at December 31, 2010. The coal seam currently being mined will sustain current production levels through 2020, at which point a new coal seam will have to be accessed in order to continue mining.

The Sufco complex currently consists of a longwall, three continuous miner sections and a loadout facility located approximately 80 miles from the mine. We ship all of the coal raw to our customers via the Union Pacific railroad or by highway trucks. Processing at the mine site consists of crushing and sizing. The rail loadout facility is capable of loading an 11,000-ton train in less than three hours.

West Elk. West Elk is an underground mining complex located on approximately 17,900 acres in Gunnison County, Colorado. The West Elk mining complex extracts steam coal from the E seam. The West Elk mining complex shipped 4.8 million tons of coal in 2010.

We control a significant portion of the coal reserves through federal and state leases. The West Elk mining complex had approximately 63.7 million tons of proven and probable reserves at December 31, 2010. Without the addition of more coal reserves, the current reserves will sustain current production levels through 2019 before annual output starts to significantly decline.

The West Elk complex currently consists of a longwall, two continuous miner sections and a loadout facility. We ship most of the coal raw to our customers via the Union Pacific railroad. In 2010, we finished constructing a new coal preparation plant with supporting coal handling facilities at the West Elk mine site. The loadout facility can load an 11,000-ton train in less than three hours.

Sales and Marketing

Overview. Coal prices are influenced by a number of factors and vary materially by region. As a result of these regional characteristics, prices of coal by product type within a given major coal producing region tend to be relatively consistent with each other. The price of coal within a region is influenced by market conditions, coal quality, transportation costs involved in moving coal from the mine to the point of use and mine operating costs. For example, higher carbon and lower ash content generally result in higher prices, and higher sulfur and higher ash content generally result in lower prices within a given geographic region.

The cost of coal at the mine is also influenced by geologic characteristics such as seam thickness, overburden ratios and depth of underground reserves. It is generally cheaper to mine coal seams that are thick and located close to the surface than to mine thin underground seams. Within a particular geographic region, underground mining, which is the primary mining method we use in the Western Bituminous region, is generally more expensive than surface mining, which is the mining method we use in the Powder River Basin and at one Western Bituminous mine. This is the case because of the higher capital costs, including costs for construction of extensive ventilation systems, and higher per unit labor costs due to lower productivity associated with underground mining.

We rely on Arch Coal’s sales and marketing force, which is principally based in St. Louis, Missouri and consists of sales personnel, transportation and distribution personnel, quality control personnel and contract administration personnel, and we pay Arch Coal for the use of their sales and marketing force under a marketing services agreement.

Customers. In 2010, we sold coal to domestic customers located in 31 different states. For the year ended December 31, 2010, we derived approximately 25% of our total coal revenues from sales to our three largest customers — Ameren Corporation, Tennessee Valley Authority and Pacificorp — and approximately 49% of our total coal revenues from sales to our 10 largest customers.

Long-Term Coal Supply Arrangements

As is customary in the coal industry, we enter into fixed price, fixed volume long-term supply contracts, the terms of which are more than one year, with many of our customers. Multiple year contracts usually have specific and possibly different volume and pricing arrangements for each year of the contract. Long-term contracts allow customers to secure a supply for their future needs and provide us with greater predictability of sales volume and sales prices. In 2010, we sold approximately 81% of our coal under long-term supply arrangements. The majority of our supply contracts include a fixed price for the term of the agreement or a pre-determined escalation in price for each year. Some of our long-term supply agreements may include a variable pricing system. While most of our sales contracts are for terms of one to five years, some are as short as one month and other contracts have terms up to 7 years. At December 31, 2010, the average volume-weighted remaining term of our long-term contracts was approximately 2.6 years, with remaining terms ranging from one to seven years. At December 31, 2010, remaining tons under long-term supply agreements, including those subject to price re-opener or extension provisions, were approximately 246 million tons.

We typically sell coal to customers under long-term arrangements through a “request-for-proposal” process. The terms of our coal sales agreements result from competitive bidding and negotiations with customers. Consequently, the terms of these contracts vary by customer, including base price adjustment features, price re-opener terms, coal quality requirements, quantity parameters, permitted sources of supply, future regulatory changes, extension options, force majeure, termination, damages and assignment provisions. Our long-term supply contracts typically contain provisions to adjust the base price due to new statutes, ordinances or regulations, such as the Mine Improvement and New Emergency Response Act of 2006, which we refer to as the MINER Act, that affect our costs related to performance of the agreement. Additionally, some of our contracts contain provisions that allow for the recovery of costs affected by modifications or changes in the interpretations or application of any applicable statute by local, state or federal government authorities. These provisions only apply to the base price of coal contained in these supply contracts. In some circumstances, a significant adjustment in base price can lead to termination of the contract.

Certain of our contracts contain index provisions that change the price based on changes in market based indices and or changes in economic indices. Certain of our contracts contain price re-opener provisions that may allow a party to commence a renegotiation of the contract price at a pre-determined time. Price re-opener provisions may automatically set a new price based on prevailing market price or, in some instances, require us to negotiate a new price, sometimes within a specified range of prices. In a limited number of agreements, if the parties do not agree on a new price, either party has an option to terminate the contract. Under some of our contracts, we have the right to match lower prices offered to our customers by other suppliers. In addition, certain of our contracts contain clauses that may allow customers to terminate the contract in the event of certain changes in environmental laws and regulations that impact their operations.

Coal quality and volumes are stipulated in coal sales agreements. In most cases, the annual pricing and volume obligations are fixed, although in some cases the volume specified may vary depending on the customer consumption requirements. Most of our coal sales agreements contain provisions requiring us to deliver coal within certain ranges for specific coal characteristics such as heat content, sulfur, ash and moisture content as well as others. Failure to meet these specifications can result in economic penalties, suspension or cancellation of shipments or termination of the contracts.

Our coal sales agreements also typically contain force majeure provisions allowing temporary suspension of performance by us or our customers, during the duration of events beyond the control of the affected party, including events such as strikes, adverse mining conditions, mine closures or serious transportation problems that affect us or unanticipated plant outages that may affect the buyer. Our contracts also generally provide that in the event a force majeure circumstance exceeds a certain time period, the unaffected party may have the option to terminate the purchase or sale in whole or in part. Some contracts stipulate that this tonnage can be made up by mutual agreement or at the discretion of the buyer. Agreements between our customers and the railroads servicing our mines may also contain force majeure provisions. Generally, our coal sales agreements allow our customer to suspend performance in the event that the railroad fails to provide its services due to circumstances that would constitute a force majeure.

In most of our contracts, we have a right of substitution (unilateral or subject to counterparty approval), allowing us to provide coal from different mines, including third-party mines, as long as the replacement coal meets quality specifications and will be sold at the same equivalent delivered cost.

In some of our coal supply contracts, we agree to indemnify or reimburse our customers for damage to their or their rail carrier’s equipment while on our property, which result from our or our agents’ negligence, and for damage to our customer’s equipment due to non-coal materials being included with our coal while on our property.

Transportation. We ship our coal to domestic customers by means of railroad, barges or trucks, or a combination of these means of transportation. We generally sell coal used for domestic consumption free on board at the mine or nearest loading facility. Our domestic customers normally bear the costs of transporting coal by rail or barge.

We generally sell coal to international customers at the export terminal, and we are usually responsible for the cost of transporting coal to the export terminals. We transport our coal to Pacific coast terminals or terminals along the Gulf of Mexico for transportation to international customers. Our international customers are generally responsible for paying the cost of ocean freight.

Historically, most domestic electricity generators have arranged long-term shipping contracts with rail or barge companies to assure stable delivery costs. Transportation can be a large component of a purchaser’s total cost. Although the purchaser pays the freight, transportation costs still are important to coal mining companies because the purchaser may choose a supplier largely based on cost of transportation. Transportation costs borne by the customer vary greatly based on each customer’s proximity to the mine and our proximity to the loadout facilities. Trucks and overland conveyors haul coal over shorter distances, while barges, Great Lake carriers and ocean vessels move coal to export markets and domestic markets requiring shipment over the Great Lakes and several river systems.

Most coal mines are served by a single rail company, but much of the Powder River Basin is served by two rail carriers: the Burlington Northern-Santa Fe railroad and the Union Pacific railroad. In the Western Bituminous region our customers are largely served by the Union Pacific railroad or by truck delivery.

Competition

The coal industry is intensely competitive. The most important factors on which we compete are coal quality, delivered costs to the customer and reliability of supply. Our principal domestic competitors include Alpha Natural Resources, Inc., Cloud Peak Energy, CONSOL Energy Inc., Massey Energy Company, Patriot Coal Corporation, and Peabody Energy Corp. Some of these coal producers are larger than we are and have greater financial resources and larger reserve bases than we do. We also compete directly with a number of smaller producers in each of the geographic regions in which we operate. As the price of domestic coal increases, we also compete with companies that produce coal from one or more foreign countries, such as Colombia, Indonesia and Venezuela.

Additionally, coal competes with other fuels, such as natural gas, nuclear energy, hydropower, wind, solar and petroleum, for steam and electrical power generation. Costs and other factors relating to these alternative fuels, such as safety and environmental considerations, affect the overall demand for coal as a fuel.

Suppliers

Principal supplies used in our business include petroleum-based fuels, explosives, tires, steel and other raw materials as well as spare parts and other consumables used in the mining process. We use third-party suppliers for a significant portion of our equipment rebuilds and repairs, drilling services and construction. We use sole source suppliers for certain parts of our business such as explosives and fuel, and preferred suppliers for other parts at our business such as dragline and shovel parts and related services. We believe adequate substitute suppliers are available. For more information about our suppliers, you should see “Risk Factors — Increases in the costs of mining and other industrial supplies, including steel-based supplies, diesel fuel and rubber tires, or the inability to obtain a sufficient quantity of those supplies, could negatively affect our operating costs or disrupt or delay our production.”

Environmental and Other Regulatory Matters.

Federal, state and local authorities regulate the U.S. coal mining industry with respect to matters such as employee health and safety and the environment, including protection of air quality, water quality, wetlands, special status species of plants and animals, land uses, cultural and historic properties and other environmental resources identified during the permitting process. Reclamation is required during production and after mining has been completed. Materials used and generated by mining operations must also be managed according to applicable regulations and law. These laws have, and will continue to have, a significant effect on our production costs and our competitive position.

We endeavor to conduct our mining operations in compliance with all applicable federal, state and local laws and regulations. However, due in part to the extensive and comprehensive regulatory requirements, violations during mining operations occur from time to time. We cannot assure you that we have been or will be at all times in complete compliance with such laws and regulations. While it is not possible to accurately quantify the expenditures we incur to maintain compliance with all applicable federal and state laws, those costs have been and are expected to continue to be significant. Federal and state mining laws and regulations require us to obtain surety bonds to guarantee performance or payment of certain long-term obligations, including mine closure and reclamation costs, federal and state workers’ compensation benefits, coal leases and other miscellaneous obligations. Compliance with these laws has substantially increased the cost of coal mining for domestic coal producers.

Future laws, regulations or orders, as well as future interpretations and more rigorous enforcement of existing laws, regulations or orders, may require substantial increases in equipment and operating costs and delays, interruptions or a termination of operations, the extent to which we cannot predict. Future laws, regulations or orders may also cause coal to become a less attractive fuel source, thereby reducing coal’s share of the market for fuels and other energy sources used to generate electricity. As a result, future laws, regulations or orders may adversely affect our mining operations, cost structure or our customers’ demand for coal.

The following is a summary of the various federal and state environmental and similar regulations that have a material impact on our business:

Mining Permits and Approvals. Numerous governmental permits or approvals are required for mining operations. When we apply for these permits and approvals, we may be required to prepare and present to federal, state or local authorities data pertaining to the effect or impact that any proposed production or processing of coal may have upon the environment. For example, in order to obtain a federal coal lease, an environmental impact statement must be prepared to assist the BLM in determining the potential environmental impact of lease issuance, including any collateral effects from the mining, transportation and burning of coal. The authorization, permitting and implementation requirements imposed by federal, state and local authorities may be costly and time consuming and may delay commencement or continuation of mining operations. In the states where we operate, the applicable laws and regulations also provide that a mining permit or modification can be delayed, refused or revoked if officers, directors, shareholders with specified interests or certain other affiliated entities with specified interests in the applicant or permittee have, or are affiliated with another entity that has, outstanding permit violations. Thus, past or ongoing violations of applicable laws and regulations could provide a basis to revoke existing permits and to deny the issuance of additional permits.

In order to obtain mining permits and approvals from federal and state regulatory authorities, mine operators must submit a reclamation plan for restoring, upon the completion of mining operations, the mined property to its prior condition or other authorized use. Typically, we submit the necessary permit applications several months or even years before we plan to begin mining a new area. Some of our required permits are becoming increasingly more difficult and expensive to obtain, and the application review processes are taking longer to complete and becoming increasingly subject to challenge, even after a permit has been issued.

Under some circumstances, substantial fines and penalties, including revocation or suspension of mining permits, may be imposed under the laws described above. Monetary sanctions and, in severe circumstances, criminal sanctions may be imposed for failure to comply with these laws.

Surface Mining Control and Reclamation Act. The Surface Mining Control and Reclamation Act, which we refer to as SMCRA, establishes mining, environmental protection, reclamation and closure standards for all aspects of surface mining as well as many aspects of underground mining. Mining operators must obtain SMCRA permits and permit renewals from the Office of Surface Mining, which we refer to as OSM, or from the applicable state agency if the state agency has obtained regulatory primacy. A state agency may achieve primacy if the state regulatory agency develops a mining regulatory program that is no less stringent than the federal mining regulatory program under SMCRA. All states in which we conduct mining operations have achieved primacy and issue permits in lieu of OSM.

SMCRA permit provisions include a complex set of requirements which include, among other things, coal prospecting; mine plan development; topsoil or growth medium removal and replacement; selective handling of overburden materials; mine pit backfilling and grading; disposal of excess spoil; protection of the hydrologic balance; subsidence control for underground mines; surface runoff and drainage control; establishment of suitable post mining land uses; and revegetation. We begin the process of preparing a mining permit application by collecting baseline data to adequately characterize the pre-mining environmental conditions of the permit area. This work is typically conducted by third-party consultants with specialized expertise and includes surveys and/or assessments of the following: cultural and historical resources; geology; soils; vegetation; aquatic organisms; wildlife; potential for threatened, endangered or other special status species; surface and ground water hydrology; climatology; riverine and riparian habitat; and wetlands. The geologic data and information derived from the other surveys and/or assessments are used to develop the mining and reclamation plans presented in the permit application. The mining and reclamation plans address the provisions and performance standards of the state’s equivalent SMCRA regulatory program, and are also used to support applications for other authorizations and/or permits required to conduct coal mining activities. Also included in the permit application is information used for documenting surface and mineral ownership, variance requests, access roads, bonding information, mining methods, mining phases, other agreements that may relate to coal, other minerals, oil and gas rights, water rights, permitted areas, and ownership and control information required to determine compliance with OSM’s Applicant Violator System, including the mining and compliance history of officers, directors and principal owners of the entity.

Once a permit application is prepared and submitted to the regulatory agency, it goes through an administrative completeness review and a thorough technical review. Also, before a SMCRA permit is issued, a mine operator must submit a bond or otherwise secure the performance of all reclamation obligations. After the application is submitted, a public notice or advertisement of the proposed permit is required to be given, which begins a notice period that is followed by a public comment period before a permit can be issued. It is not uncommon for a SMCRA mine permit application to take over a year to prepare, depending on the size and complexity of the mine, and anywhere from six months to two years or even longer for the permit to be issued. The variability in time frame required to prepare the application and issue the permit can be attributed primarily to the various regulatory authorities’ discretion in the handling of comments and objections relating to the project received from the general public and other agencies. Also, it is not uncommon for a permit to be delayed as a result of litigation related to the specific permit or another related company’s permit.

In addition to the bond requirement for an active or proposed permit, the Abandoned Mine Land Fund, which was created by SMCRA, requires a fee on all coal produced. The proceeds of the fee are used to restore mines closed or abandoned prior to SMCRA’s adoption in 1977. The current fee is $0.315 per ton of coal produced from surface mines and $0.135 per ton of coal produced from underground mines. In 2010, we recorded $41.9 million of expense related to these reclamation fees.

Surety Bonds. Mine operators are often required by federal and/or state laws, including SMCRA, to assure, usually through the use of surety bonds, payment of certain long-term obligations including mine closure or reclamation costs, federal and state workers’ compensation costs, coal leases and other miscellaneous obligations. Although surety bonds are usually noncancelable during their term, many of these bonds are renewable on an annual basis.

The costs of these bonds have fluctuated in recent years while the market terms of surety bonds have generally become more unfavorable to mine operators. These changes in the terms of the bonds have been accompanied at times by a decrease in the number of companies willing to issue surety bonds. In order to address some of these uncertainties, we use self-bonding to secure performance of certain obligations in Wyoming. As of December 31, 2010, we have self-bonded an aggregate of approximately $403 million and have posted an aggregate of approximately $33 million in surety bonds for reclamation purposes. In addition, we had approximately $21 million of surety bonds and letters of credit outstanding at December 31, 2010 to secure workers’ compensation, coal lease and other obligations.

Mine Safety and Health. Stringent safety and health standards have been imposed by federal legislation since Congress adopted the Mine Safety and Health Act of 1969. The Mine Safety and Health Act of 1977 significantly expanded the enforcement of safety and health standards and imposed comprehensive safety and health standards on all aspects of mining operations. In addition to federal regulatory programs, all of the states in which we operate also have programs aimed at improving mine safety and health. Collectively, federal and state safety and health regulation in the coal mining industry is among the most comprehensive and pervasive systems for the protection of employee health and safety affecting any segment of U.S. industry. In

reaction to recent mine accidents, federal and state legislatures and regulatory authorities have increased scrutiny of mine safety matters and passed more stringent laws governing mining. For example, in 2006, Congress enacted the MINER Act. The MINER Act imposes additional obligations on coal operators including, among other things, the following:

	•		development of new emergency response plans that address post-accident communications, tracking of miners, breathable air, lifelines, training and communication with local emergency response personnel;

	•		establishment of additional requirements for mine rescue teams;

	•		notification of federal authorities in the event of certain events;

	•		increased penalties for violations of the applicable federal laws and regulations; and

	•		requirement that standards be implemented regarding the manner in which closed areas of underground mines are sealed.

In 2008, the U.S. House of Representatives approved additional federal legislation which would have required new regulations on a variety of mine safety issues such as underground refuges, mine ventilation and communication systems. Although the U.S. Senate failed to pass that legislation, it is possible that similar legislation may be proposed in the future. Various states, including West Virginia, have also enacted new laws to address many of the same subjects. The costs of implementing these new safety and health regulations at the federal and state level have been, and will continue to be, substantial. In addition to the cost of implementation, there are increased penalties for violations which may also be substantial. Expanded enforcement has resulted in a proliferation of litigation regarding citations and orders issued as a result of the regulations.

Under the Black Lung Benefits Revenue Act of 1977 and the Black Lung Benefits Reform Act of 1977, each coal mine operator must secure payment of federal black lung benefits to claimants who are current and former employees and to a trust fund for the payment of benefits and medical expenses to claimants who last worked in the coal industry prior to July 1, 1973. The trust fund is funded by an excise tax on production of up to $1.10 per ton for coal mined in underground operations and up to $0.55 per ton for coal mined in surface operations. These amounts may not exceed 4.4% of the gross sales price. This excise tax does not apply to coal shipped outside the United States. In 2010, we recorded $74.3 million of expense related to this excise tax.

Clean Air Act. The federal Clean Air Act and similar state and local laws that regulate air emissions affect coal mining directly and indirectly. Direct impacts on coal mining and processing operations include Clean Air Act permitting requirements and emissions control requirements relating to particulate matter which may include controlling fugitive dust. The Clean Air Act also indirectly affects coal mining operations by extensively regulating the emissions of fine particulate matter measuring 2.5 micrometers in diameter or smaller, sulfur dioxide, nitrogen oxides, mercury and other compounds emitted by coal-fueled power plants and industrial boilers, which are the largest end-users of our coal. Continued tightening of the already stringent regulation of emissions is likely, such as the Environmental Protection Agency’s (“EPA”) June 22, 2010, (75 Fed Reg 35520) revision of the national ambient air quality standard for sulfur dioxide and a similar proposal announced on January 6, 2010 for ozone that is now expected to be finalized in July of 2011. Regulation of additional emissions such as carbon dioxide or other greenhouse gases as proposed or determined by EPA on October 27, October 30 and December 15, 2009 may eventually be applied to stationary sources such as coal-fueled power plants and industrial boilers (see discussion of Climate Change, below). This application could eventually reduce the demand for coal.

Clean Air Act requirements that may directly or indirectly affect our operations include the following:

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Acid Rain. Title IV of the Clean Air Act, promulgated in 1990, imposed a two-phase reduction of sulfur dioxide emissions by electric utilities. Phase II became effective in 2000 and applies to all coal-fueled power plants with a capacity of more than 25-megawatts. Generally, the affected power plants have sought to comply with these requirements by switching to lower sulfur fuels, installing pollution control devices, reducing electricity generating levels or purchasing or trading sulfur dioxide emissions allowances. Although we cannot accurately predict the future effect of this Clean Air Act provision on our operations, we believe that implementation of Phase II has been factored into the pricing of the coal market.

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Particulate Matter. The Clean Air Act requires the U.S. Environmental Protection Agency, which we refer to as EPA, to set national ambient air quality standards, which we refer to as NAAQS, for certain pollutants associated with the combustion of coal, including sulfur dioxide, particulate matter, nitrogen oxides and ozone. Areas that are not in compliance with these standards, referred to as non-attainment areas, must take steps to reduce emissions levels. For example, NAAQS currently exist for particulate matter measuring 10 micrometers in diameter or smaller (PM10) and for fine particulate matter measuring 2.5 micrometers in diameter or smaller (PM2.5). The EPA designated all or part of 225 counties in 20 states as well as the District of Columbia as non-attainment areas with respect to the PM2.5 NAAQS. Those designations have been challenged. Individual states must identify the sources of emissions and develop emission reduction plans. These plans may

be state-specific or regional in scope. Under the Clean Air Act, individual states have up to 12 years from the date of designation to secure emissions reductions from sources contributing to the problem. In addition, EPA has announced that it intends to propose a revision to the PM2.5 NAAQS in February of 2011 with a final regulation being promulgated in October of 2011. Future regulation and enforcement of the new PM2.5 standard will affect many power plants, especially coal-fueled power plants, and all plants in non-attainment areas.

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Ozone. Significant additional emission control expenditures will be required at coal-fueled power plants to meet the new NAAQS for ozone. Nitrogen oxides, which are a byproduct of coal combustion, are classified as an ozone precursor. As a result, emissions control requirements for new and expanded coal-fueled power plants and industrial boilers will continue to become more demanding in the years ahead. For example, on March 27, 2008, EPA promulgated a new 75 parts per billion (ppb) ozone primary NAAQS. On September 16, 2009, EPA announced that it will reconsider the new standard, and on January 19, 2010, EPA proposed its reconsidered NAAQS (75 Fed Reg 2938), proposing to adopt a new, more stringent primary ambient air quality standard for ozone and to change the way in which the secondary standard is calculated. Should these NAAQS withstand scrutiny, additional emission control expenditures will likely be required at coal-fueled power plants.

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NOx SIP Call. The NOx SIP Call program was established by the EPA in October 1998 to reduce the transport of ozone on prevailing winds from the Midwest and South to states in the Northeast, which said that they could not meet federal air quality standards because of migrating pollution. The program was designed to reduce nitrous oxide emissions by one million tons per year in 22 eastern states and the District of Columbia. Phase II reductions were required by May 2007. As a result of the program, many power plants have been or will be required to install additional emission control measures, such as selective catalytic reduction devices. Installation of additional emission control measures will make it more costly to operate coal-fueled power plants, which could make coal a less attractive fuel.

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Clean Air Interstate Rule. The EPA finalized the Clean Air Interstate Rule, which we refer to as CAIR, in March 2005. CAIR calls for power plants in 28 eastern states and the District of Columbia to reduce emission levels of sulfur dioxide and nitrous oxide pursuant to a cap and trade program similar to the system now in effect for acid deposition control and to that proposed by the Clean Skies Initiative. The stringency of the cap may require some coal-fueled power plants to install additional pollution control equipment, such as wet scrubbers, which could decrease the demand for low-sulfur coal at these plants and thereby potentially reduce market prices for low-sulfur coal. Emissions are permanently capped and cannot increase. In July 2008, in State of North Carolina v. EPA and consolidated cases, the U.S. Court of Appeals for the District of Columbia Circuit disagreed with the EPA’s reading of the Clean Air Act and vacated CAIR in its entirety. In December 2008, the U.S. Court of Appeals for the District of Columbia Circuit revised its remedy and remanded the rule to the EPA. EPA proposed a revised transport rule on August 2, 2010, (75 Fed Reg 45209) and received thousands of comments on the proposal. The rule making is expected to be finalized in July of 2011 and it is possible that additional power plant controls may be required under the replacement rule, which may affect the market for coal.

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Mercury. In February 2008, the U.S. Court of Appeals for the District of Columbia Circuit vacated the EPA’s Clean Air Mercury Rule, which we refer to as CAMR, and remanded it to the EPA for reconsideration. The EPA is reviewing the court decision and evaluating its impacts. Before the court decision, some states had either adopted CAMR or adopted state-specific rules to regulate mercury emissions from power plants that are more stringent than CAMR. CAMR, as promulgated, would have permanently capped and reduced mercury emissions from coal-fueled power plants by establishing mercury emissions limits from new and existing coal-fueled power plants and creating a market-based cap-and-trade program that was expected to reduce nationwide emissions of mercury in two phases. Under CAMR, coal-fueled power plants would have had until 2010 to cut mercury emission levels from 48 tons to 38 tons a year and until 2018 to bring that level down to 15 tons, a 69% reduction. On December 24, 2009, the EPA announced that it had recommended to the Office of Management and Budget an Information Collection Request that would require all US power plants with coal or oil-fired generating units to submit emissions information. With this information the EPA intends to propose standards for all air toxic emissions, including mercury, for coal and oil-fired units by March 10, 2011. The EPA hopes to make these new standards final by November 16, 2011. Regardless of how the EPA responds on reconsideration or how states implement their state-specific mercury rules, rules imposing stricter limitations on mercury emissions from power plants will likely be promulgated and implemented. Any such rules may adversely affect the demand for coal.

•

Regional Haze. The EPA has initiated a regional haze program designed to protect and improve visibility at and around national parks, national wilderness areas and international parks, particularly those located in the southwest and southeast United States. Under the Regional Haze Rule, affected states were required to submit regional haze SIP’s by December 17, 2007, that, among other things, was to identify facilities that would have to reduce emissions and comply with stricter emission limitations. The vast majority of states failed to submit their plans by December 17, 2007, and EPA issued a Finding of Failure to Submit plans on January 15, 2009 (74 Fed. Reg. 2392), which could trigger Federal implementation plans. EPA has taken no enforcement action against states to finalize implementation plans. Nonetheless, this program may result in additional emissions restrictions from new coal-fueled power plants whose operations may impair visibility at and

around federally protected areas. This program may also require certain existing coal-fueled power plants to install additional control measures designed to limit haze-causing emissions, such as sulfur dioxide, nitrogen oxides, volatile organic chemicals and particulate matter. These limitations could affect the future market for coal.

•

New Source Review. A number of pending regulatory changes and court actions are affecting the scope of the EPA’s new source review program, which under certain circumstances requires existing coal-fueled power plants to install the more stringent air emissions control equipment required of new plants. The changes to the new source review program may impact demand for coal nationally, but as the final form of the requirements after their revision is not yet known, we are unable to predict the magnitude of the impact.

Climate Change. One by-product of burning coal is carbon dioxide, which is considered a greenhouse gas and is a major source of concern with respect to global warming. In November 2004, Russia ratified the Kyoto Protocol to the 1992 Framework Convention on Global Climate Change, which establishes a binding set of emission targets for greenhouse gases. With Russia’s acceptance, the Kyoto Protocol became binding on all those countries that had ratified it in February 2005. The United States has refused to ratify the Kyoto Protocol. Although the Kyoto targets varied from country to country, the United States Kyoto Protocol target reductions of greenhouse gas emissions would be to 93% of 1990 levels. Following the Kyoto meeting, multiple Conferences of the Parties have been held. None to date, including the most recent Conference of the Parties in Cancun, Mexico, in late November and early December of 2010, have resulted in any mandatory reduction requirements for the United States, but any such future conference may do so.

Future regulation of greenhouse gases in the United States could occur pursuant to future U.S. treaty obligations, statutory or regulatory changes under the Clean Air Act, federal or state adoption of a greenhouse gas regulatory scheme, or otherwise. The U.S. Congress has considered various proposals to reduce greenhouse gas emissions, but to date, none have become law. In April 2007, the U.S. Supreme Court rendered its decision in Massachusetts v. EPA, finding that the EPA has authority under the Clean Air Act to regulate carbon dioxide emissions from automobiles and can decide against regulation only if the EPA determines that carbon dioxide does not significantly contribute to climate change and does not endanger public health or the environment. On December 15, 2009, EPA published a formal determination that six greenhouse gases, including carbon dioxide and methane, endanger both the public health and welfare of current and future generations. In the same Federal Register rulemaking, EPA found that emission of greenhouse gases from new motor vehicles and their engines contribute to greenhouse gas pollution. Although Massachusetts v. EPA did not involve the EPA’s authority to regulate greenhouse gas emissions from stationary sources, such as coal-fueled power plants, the decision is likely to impact regulation of stationary sources.

For example, a challenge in the U.S. Court of Appeals for the District of Columbia with respect to the EPA’s decision not to regulate greenhouse gas emissions from power plants and other stationary sources under the Clean Air Act’s new source performance standards was remanded to the EPA for further consideration in light of Massachusetts v. EPA. Other pending cases regarding greenhouse gases may affect the market for coal. In AEP v. Connecticut (582 F. 3d, 309, 2d Cir, 2009) the Second Circuit Court of Appeals held that States and private plaintiffs may maintain actions under federal common law alleging that five electric utilities have created a “public nuisance” by contributing to global warming, and may seek injunctive relief capping the utilities’ CO₂ emissions at judicially-determined levels. However, the Supreme Court granted certiorari (10-174, US) on December 6, 2010, and argument has not yet been scheduled.

On October 27, 2009, the EPA announced how it will establish thresholds for phasing-in and regulating greenhouse gas emissions under various provisions of the Clean Air Act. Three days later, on October 30, 2009, the EPA published a final rule in the Federal Register that requires the reporting of greenhouse gas emissions from all sectors of the American economy, and reporting of emissions from underground coal mines and coal suppliers was promulgated on July 12, 2010 (75 Fed Reg 39736). If as a result of these actions the EPA were to set emission limits for carbon dioxide from electric utilities or steel mills, the demand for coal could decrease.

In the absence of federal legislation or regulation, many states and regions have adopted greenhouse gas initiatives. These state and regional climate change rules will likely require additional controls on coal-fueled power plants and industrial boilers and may even cause some users of coal to switch from coal to a lower carbon fuel. There can be no assurance at this time that a carbon dioxide cap and trade program, a carbon tax or other regulatory regime, if implemented by the states in which our customers operate or at the federal level, will not affect the future market for coal in those regions. The permitting of new coal-fueled power plants has also recently been contested by state regulators and environmental organizations based on concerns relating to greenhouse gas emissions. Increased efforts to control greenhouse gas emissions could result in reduced demand for coal.

Clean Water Act. The federal Clean Water Act and corresponding state and local laws and regulations affect coal mining operations by restricting the discharge of pollutants, including dredged and fill materials, into waters of the United States. The Clean Water Act provisions and associated state and federal regulations are complex and subject to amendments, legal challenges and changes in implementation. Recent court decisions and regulatory actions have created uncertainty over Clean Water Act

jurisdiction and permitting requirements that could variously increase or decrease the cost and time we expend on Clean Water Act compliance.

Clean Water Act requirements that may directly or indirectly affect our operations include the following:

•

Wastewater Discharge. Section 402 of the Clean Water Act creates a process for establishing effluent limitations for discharges to streams that are protective of water quality standards through the National Pollutant Discharge Elimination System, which we refer to as the NPDES, or an equally stringent program delegated to a state regulatory agency. Regular monitoring, reporting and compliance with performance standards are preconditions for the issuance and renewal of NPDES permits that govern discharges into waters of the United States, especially on selenium, sulfate and specific conductance. Discharges that exceed the limits specified under NPDES permits can lead to the imposition of penalties, and persistent non-compliance could lead to significant penalties, compliance costs and delays in coal production. In addition, the imposition of future restrictions on the discharge of certain pollutants into waters of the United States could increase the difficulty of obtaining and complying with NPDES permits, which could impose additional time and cost burdens on our operations.

Discharges of pollutants into waters that states have designated as impaired (i.e., as not meeting present water quality standards) are subject to Total Maximum Daily Load, which we refer to as TMDL, regulations. The TMDL regulations establish a process for calculating the maximum amount of a pollutant that a water body can receive while maintaining state water quality standards. Pollutant loads are allocated among the various sources that discharge pollutants into that water body. Mine operations that discharge into water bodies designated as impaired will be required to meet new TMDL allocations. The adoption of more stringent TMDL-related allocations for our coal mines could require more costly water treatment and could adversely affect our coal production.

The Clean Water Act also requires states to develop anti-degradation policies to ensure that non-impaired water bodies continue to meet water quality standards. The issuance and renewal of permits for the discharge of pollutants to waters that have been designated as “high quality” are subject to anti-degradation review that may increase the costs, time and difficulty associated with obtaining and complying with NPDES permits.

Resource Conservation and Recovery Act. The Resource Conservation and Recovery Act, which we refer to as RCRA, may affect coal mining operations through its requirements for the management, handling, transportation and disposal of hazardous wastes. Currently, certain coal mine wastes, such as overburden and coal cleaning wastes, are exempted from hazardous waste management. In addition, Subtitle C of RCRA exempted fossil fuel combustion wastes from hazardous waste regulation until the EPA completed a report to Congress and made a determination on whether the wastes should be regulated as hazardous. In its 1993 regulatory determination, the EPA addressed some high volume-low toxicity coal combustion products generated at electric utility and independent power producing facilities, such as coal ash, and left the exemption in place. In May 2000, the EPA concluded that coal combustion products do not warrant regulation as hazardous waste under RCRA and again retained the hazardous waste exemption for these wastes. The EPA also determined that national non-hazardous waste regulations under RCRA Subtitle D are needed for coal combustion products disposed in surface impoundments and landfills and used as mine-fill. In March of 2007 the Office of Surface Mining and EPA proposed regulations regarding the management of coal combustion products. The EPA concluded that beneficial uses of these wastes, other than for mine-filling, pose no significant risk and no additional national regulations are needed. As long as this exemption remains in effect, it is not anticipated that regulation of coal combustion waste will have any material effect on the amount of coal used by electricity generators. A final rule has not been promulgated. Most state hazardous waste laws also exempt coal combustion products, and instead treat it as either a solid waste or a special waste. Any costs associated with handling or disposal of hazardous wastes would increase our customers’ operating costs and potentially reduce their ability to purchase coal. In addition, contamination caused by the past disposal of ash can lead to material liability. In another development regarding coal combustion wastes, EPA conducted an assessment of impoundments and other units that manage residuals from coal combustion and that contain free liquids following a massive coal ash spill in Tennessee in 2008, EPA contractors conducted site assessments at many impoundments and is requiring appropriate remedial action at any facility that is found to have a unit posing a risk for potential failure. EPA is posting utility responses to the assessment on its web site as the responses are received. Future regulations resulting from the EPA coal combustion refuse assessments may impact the ability of the Company’s utility customers to continue to use coal in their power plants.

Comprehensive Environmental Response, Compensation and Liability Act. The Comprehensive Environmental Response, Compensation and Liability Act, which we refer to as CERCLA, and similar state laws affect coal mining operations by, among other things, imposing cleanup requirements for threatened or actual releases of hazardous substances that may endanger public health or welfare or the environment. Under CERCLA and similar state laws, joint and several liability may be imposed on waste generators, site owners and lessees and others regardless of fault or the legality of the original disposal activity. Although the EPA excludes most wastes generated by coal mining and processing operations from the hazardous waste laws, such wastes can, in certain circumstances, constitute hazardous substances for the purposes of CERCLA. In addition, the disposal, release or spilling of some products used by coal companies in operations, such as chemicals, could trigger the liability provisions of the statute. Thus, coal mines that we currently own or have previously owned or operated, and sites to which we sent waste materials, may be

subject to liability under CERCLA and similar state laws. In particular, we may be liable under CERCLA or similar state laws for the cleanup of hazardous substance contamination at sites where we own surface rights.

Endangered Species. The Endangered Species Act and other related federal and state statutes protect species threatened or endangered with possible extinction. Protection of threatened, endangered and other special status species may have the effect of prohibiting or delaying us from obtaining mining permits and may include restrictions on timber harvesting, road building and other mining or agricultural activities in areas containing the affected species. A number of species indigenous to our properties are protected under the Endangered Species Act or other related laws or regulations. Based on the species that have been identified to date and the current application of applicable laws and regulations, however, we do not believe there are any species protected under the Endangered Species Act that would materially and adversely affect our ability to mine coal from our properties in accordance with current mining plans. We have been able to continue our operations within the existing spatial, temporal and other restrictions associated with special status species. Should more stringent protective measures be applied to threatened, endangered or other special status species or to their critical habitat, then we could experience increased operating costs or difficulty in obtaining future mining permits.

Use of Explosives. Our surface mining operations are subject to numerous regulations relating to blasting activities. Pursuant to these regulations, we incur costs to design and implement blast schedules and to conduct pre-blast surveys and blast monitoring. In addition, the storage of explosives is subject to strict regulatory requirements established by four different federal regulatory agencies. For example, pursuant to a rule issued by the Department of Homeland Security in 2007, facilities in possession of chemicals of interest, including ammonium nitrate at certain threshold levels, must complete a screening review in order to help determine whether there is a high level of security risk such that a security vulnerability assessment and site security plan will be required.

Other Environmental Laws. We are required to comply with numerous other federal, state and local environmental laws in addition to those previously discussed. These additional laws include, for example, the Safe Drinking Water Act, the Toxic Substance Control Act and the Emergency Planning and Community Right-to-Know Act.

Employees

General. At March 28, 2011, we employed a total of approximately 3,000 persons. We believe that our relations with all employees are good.

Executive Officers

Our managing member is an indirect, wholly-owned subsidiary of Arch Coal. As a result, we are effectively managed by the management of Arch Coal. The following is a list of executive officers of Arch Coal, their ages as of February 22, 2011 and their positions and offices during the last five years:


Name	Age		Position
C. Henry Besten, Jr.		62	Mr. Besten has served as Arch Coal’s Senior Vice President-Strategic Development since 2002.

John T. Drexler		41	Mr. Drexler has served as Arch Coal’s Senior Vice President and Chief Financial Officer since April 2008. Mr. Drexler served as Arch Coal’s Vice President-Finance and Accounting from March 2006 to April 2008. From March 2005 to March 2006, Mr. Drexler served as Arch Coal’s Director of Planning and Forecasting. Prior to March 2005, Mr. Drexler held several other positions within Arch Coal’s finance and accounting department.

John W. Eaves		53	Mr. Eaves has served as Arch Coal’s President and Chief Operating Officer since April 2006. Mr. Eaves has also been a director of Arch Coal since February 2006. From 2002 to April 2006, Mr. Eaves served as Arch Coal’s Executive Vice President and Chief Operating Officer. Mr. Eaves also serves on the board of directors of ADA-ES, Inc. and CoaLogix.

Sheila B. Feldman		56	Ms. Feldman has served as Arch Coal’s Vice President-Human Resources since 2003. From 1997 to 2003, Ms. Feldman was the Vice President-Human Resources and Public Affairs of Solutia Inc.

Robert G. Jones		54	Mr. Jones has served as Arch Coal’s Senior Vice President-Law, General Counsel and Secretary since August 2008. Mr. Jones served as Vice President-Law, General Counsel and Secretary from 2000 to August 2008.


Name	Age		Position
Paul A. Lang		50	Mr. Lang has served as Arch Coal’s Senior Vice President-Operations since December 2006. Mr. Lang served as President of Western Operations from July 2005 through December 2006 and President and General Manager of Thunder Basin Coal Company, L.L.C. from 1998 through July 2005.

Steven F. Leer		58	Mr. Leer has served as Arch Coal’s Chairman and Chief Executive Officer since April 2006. Mr. Leer served as Arch Coal’s President and Chief Executive Officer from 1992 to April 2006. Mr. Leer also serves on the board of directors of the Norfolk Southern Corporation, USG Corp., the Business Roundtable, the University of the Pacific and Washington University and is past chairman of the Coal Industry Advisory Board. Mr. Leer is a past chairman and continues to serve on the board of directors of the Center for Energy and Economic Development, the National Coal Council and the National Mining Association.

David B. Peugh		56	Mr. Peugh has served as Arch Coal’s Vice President-Business Development since 1995.

Deck S. Slone		47	Mr. Slone has served as Arch Coal’s Vice President-Government, Investor and Public Affairs since August 2008. Mr. Slone served as Arch Coal’s Vice President-Investor Relations and Public Affairs from 2001 to August 2008.

David N. Warnecke		55	Mr. Warnecke is currently Arch Coal’s Senior Vice President–Marketing and Trading. He has served as Arch Coal’s Vice President-Marketing and Trading from August 2005 until February 2011. From June 2005 until March 2007, Mr. Warnecke served as President of Arch Coal Sales Company, Inc. and from April 2004 until June 2005, Mr. Warnecke served as Executive Vice President of Arch Coal Sales Company, Inc. Prior to June 2004, Mr. Warnecke was Senior Vice President-Sales, Trading and Transportation of Arch Coal Sales Company, Inc.

Available Information

We file annual, quarterly and current reports, and amendments to those reports, proxy statements and other information with the Securities and Exchange Commission. You may access and read our filings without charge through the SEC’s website, at sec.gov. You may also read and copy any document we file at the SEC’s public reference room located at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference room.

We also make the documents listed above available without charge through Arch Coal, Inc.’s website, archcoal.com, as soon as practicable after we file or furnish them with the SEC. You may also request copies of the documents, at no cost, by telephone at (314) 994-2700 or by mail at Arch Coal, Inc., One CityPlace Drive, Suite 300, St. Louis, Missouri, 63141 Attention: Vice President-Government, Investor and Public Affairs. The information on Arch Coal, Inc.’s website is not part of this Annual Report on Form 10-K.

GLOSSARY OF SELECTED MINING TERMS

Certain terms that we use in this document are specific to the coal mining industry and may be technical in nature. The following is a list of selected mining terms and the definitions we attribute to them.


Assigned reserves		Recoverable reserves designated for mining by a specific operation.

Btu		A measure of the energy required to raise the temperature of one pound of water one degree of Fahrenheit.

Compliance coal		Coal which, when burned, emits 1.2 pounds or less of sulfur dioxide per million Btus, requiring no blending or other sulfur dioxide reduction technologies in order to comply with the requirements of the Clean Air Act.

Continuous miner		A machine used in underground mining to cut coal from the seam and load it onto conveyors or into shuttle cars in a continuous operation.

Dragline		A large machine used in surface mining to remove the overburden, or layers of


		earth and rock, covering a coal seam. The dragline has a large bucket, suspended by cables from the end of a long boom, which is able to scoop up large amounts of overburden as it is dragged across the excavation area and redeposit the overburden in another area.

Longwall mining		One of two major underground coal mining methods, generally employing two rotating drums pulled mechanically back and forth across a long face of coal.

Low-sulfur coal		Coal which, when burned, emits 1.6 pounds or less of sulfur dioxide per million Btus.

Preparation plant		A facility used for crushing, sizing and washing coal to remove impurities and to prepare it for use by a particular customer.

Probable reserves		Reserves for which quantity and grade and/or quality are computed from information similar to that used for proven reserves, but the sites for inspection, sampling and measurement are farther apart or are otherwise less adequately spaced.

Proven reserves		Reserves for which (a) quantity is computed from dimensions revealed in outcrops, trenches, workings or drill holes; grade and/or quality are computed from the results of detailed sampling and (b) the sites for inspection, sampling and measurement are spaced so closely and the geologic character is so well defined that size, shape, depth and mineral content of reserves are well established.

Reclamation		The restoration of land and environmental values to a mining site after the coal is extracted. The process commonly includes “recontouring” or shaping the land to its approximate original appearance, restoring topsoil and planting native grass and ground covers.

Recoverable reserves		The amount of proven and probable reserves that can actually be recovered from the reserve base taking into account all mining and preparation losses involved in producing a saleable product using existing methods and under current law.

Reserves		That part of a mineral deposit which could be economically and legally extracted or produced at the time of the reserve determination.

Unassigned reserves		Recoverable reserves that have not yet been designated for mining by a specific operation.

ITEM 1A. RISK FACTORS.

Our business involves certain risks and uncertainties. In addition to the risks and uncertainties described below, we may face other risks and uncertainties, some of which may be unknown to us and some of which we may deem immaterial. If one or more of these risks or uncertainties occur, our business, financial condition or results of operations may be materially and adversely affected.

Risks Related to Our Business

Coal prices are subject to change and a substantial or extended decline in prices could materially and adversely affect our profitability and the value of our coal reserves.

Our profitability and the value of our coal reserves depend upon the prices we receive for our coal. The contract prices we may receive in the future for coal depend upon factors beyond our control, including the following:

	•		the domestic and foreign supply and demand for coal;

	•		the quantity and quality of coal available from competitors;

	•		competition for production of electricity from non-coal sources, including the price and availability of alternative fuels;

	•		domestic air emission standards for coal-fueled power plants and the ability of coal-fueled power plants to meet these standards by installing scrubbers or other means;

	•		adverse weather, climatic or other natural conditions, including natural disasters;

	•		domestic and foreign economic conditions, including economic slowdowns;

	•		legislative, regulatory and judicial developments, environmental regulatory changes or changes in energy policy and energy conservation measures that would adversely affect the coal industry, such as legislation limiting carbon emissions or providing for increased funding and incentives for alternative energy sources;

	•		the proximity to, capacity of and cost of transportation and port facilities; and

	•		market price fluctuations for sulfur dioxide emission allowances.

A substantial or extended decline in the prices we receive for our future coal sales contracts could materially and adversely affect us by decreasing our profitability and the value of our coal reserves.

Our coal mining operations are subject to operating risks that are beyond our control, which could result in materially increased operating expenses and decreased production levels and could materially and adversely affect our profitability.

We mine coal at underground and surface mining operations. Certain factors beyond our control, including those listed below, could disrupt our coal mining operations, adversely affect production and shipments and increase our operating costs:

	•		poor mining conditions resulting from geological, hydrologic or other conditions that may cause instability of highwalls or spoil piles or cause damage to nearby infrastructure or mine personnel;

	•		a major incident at the mine site that causes all or part of the operations of the mine to cease for some period of time;

	•		mining, processing and plant equipment failures and unexpected maintenance problems;

	•		adverse weather and natural disasters, such as heavy rains or snow, flooding and other natural events affecting operations, transportation or customers;

	•		unexpected or accidental surface subsidence from underground mining;

	•		accidental mine water discharges, fires, explosions or similar mining accidents; and

	•		competition and/or conflicts with other natural resource extraction activities and production within our operating areas, such as coalbed methane extraction or oil and gas development.

If any of these conditions or events occurs, particularly at our Black Thunder mining complex, which accounted for approximately 81% of the coal volume we sold in 2010, our coal mining operations may be disrupted, we could experience a delay or halt of production or shipments or our operating costs could increase significantly. In addition, if our insurance coverage is limited or excludes certain of these conditions or events, then we may not be able to recover any of the losses we may incur as a result of such conditions or events, some of which may be substantial.

Competition within the coal industry could put downward pressure on coal prices and, as a result, materially and adversely affect our revenues and profitability.

We compete with numerous other coal producers in various regions of the United States for domestic sales. International demand for U.S. coal also affects competition within our industry. The demand for U.S. coal exports depends upon a number of factors outside our control, including the overall demand for electricity in foreign markets, currency exchange rates, ocean freight rates, port and shipping capacity, the demand for foreign-priced steel, both in foreign markets and in the U.S. market, general economic conditions in foreign countries, technological developments and environmental and other governmental regulations. Foreign demand for certain U.S. coal has increased in recent periods. If foreign demand for U.S. coal were to decline, this decline could cause competition among coal producers for the sale of coal in the United States to intensify, potentially resulting in significant downward pressure on domestic coal prices.

In addition, during the mid-1970s and early 1980s, increased demand for coal attracted new investors to the coal industry, spurred the development of new mines and resulted in additional production capacity throughout the industry, all of which led to increased competition and lower coal prices. Increases in coal prices over the past several years have encouraged the development of expanded capacity by coal producers and may continue to do so. Any resulting overcapacity and increased production could materially reduce coal prices and therefore materially reduce our revenues and profitability.

Decreases in demand for electricity resulting from economic, weather changes or other conditions could adversely affect coal prices and materially and adversely affect our results of operations.

Our coal is primarily used as fuel for electricity generation. Overall economic activity and the associated demand for power by industrial users can have significant effects on overall electricity demand. An economic slowdown can significantly slow the growth of electrical demand and could result in contraction of demand for coal. Declines in international prices for coal generally will impact U.S. prices for coal. During the past several years, international demand for coal has been driven, in significant part, by fluctuations in demand due to economic growth in China and India as well as other developing countries. Significant declines in

the rates of economic growth in these regions could materially affect international demand for U.S. coal, which may have an adverse effect on U.S. coal prices.

Weather patterns can also greatly affect electricity demand. Extreme temperatures, both hot and cold, cause increased power usage and, therefore, increased generating requirements from all sources. Mild temperatures, on the other hand, result in lower electrical demand, which allows generators to choose the sources of power generation when deciding which generation sources to dispatch. Any downward pressure on coal prices, due to decreases in overall demand or otherwise, including changes in weather patterns, would materially and adversely affect our results of operations.

The use of alternative energy sources for power generation could reduce coal consumption by U.S. electric power generators, which could result in lower prices for our coal. Declines in the prices at which we sell our coal could reduce our revenues and materially and adversely affect our business and results of operations.

In 2010, approximately 78% of the tons we sold were to domestic electric power generators. The amount of coal consumed for U.S. electric power generation is affected by, among other things:

	•		the location, availability, quality and price of alternative energy sources for power generation, such as natural gas, fuel oil, nuclear, hydroelectric, wind, biomass and solar power; and

	•		technological developments, including those related to alternative energy sources.

Gas-fueled generation has the potential to displace coal-fueled generation, particularly from older, less efficient coal-powered generators. We expect that many of the new power plants needed to meet increasing demand for electricity generation will be fueled by natural gas because gas-fired plants are cheaper to construct and permits to construct these plants are easier to obtain as natural gas is seen as having a lower environmental impact than coal-fueled generators. In addition, state and federal mandates for increased use of electricity from renewable energy sources could have an impact on the market for our coal. Several states have enacted legislative mandates requiring electricity suppliers to use renewable energy sources to generate a certain percentage of power. There have been numerous proposals to establish a similar uniform, national standard although none of these proposals have been enacted to date. Possible advances in technologies and incentives, such as tax credits, to enhance the economics of renewable energy sources could make these sources more competitive with coal. Any reduction in the amount of coal consumed by domestic electric power generators could reduce the price of coal that we mine and sell, thereby reducing our revenues and materially and adversely affecting our business and results of operations.

Our inability to acquire additional coal reserves or our inability to develop coal reserves in an economically feasible manner may adversely affect our business.

Our profitability depends substantially on our ability to mine and process, in a cost-effective manner, coal reserves that possess the quality characteristics desired by our customers. As we mine, our coal reserves decline. As a result, our future success depends upon our ability to acquire additional coal that is economically recoverable. If we fail to acquire or develop additional coal reserves, our existing reserves will eventually be depleted. We may not be able to obtain replacement reserves when we require them. If available, replacement reserves may not be available at favorable prices, or we may not be capable of mining those reserves at costs that are comparable with our existing coal reserves. Our ability to obtain coal reserves in the future could also be limited by the availability of cash we generate from our operations or available financing, restrictions under our existing or future financing arrangements, and competition from other coal producers, the lack of suitable acquisition or lease-by-application, or LBA, opportunities or the inability to acquire coal properties or LBAs on commercially reasonable terms. If we are unable to acquire replacement reserves, our future production may decrease significantly and our operating results may be negatively affected. In addition, we may not be able to mine future reserves as profitably as we do at our current operations.

Inaccuracies in our estimates of our coal reserves could result in decreased profitability from lower than expected revenues or higher than expected costs.

Our future performance depends on, among other things, the accuracy of our estimates of our proven and probable coal reserves. We base our estimates of reserves on engineering, economic and geological data assembled, analyzed and reviewed by internal and third-party engineers and consultants. We update our estimates of the quantity and quality of proven and probable coal reserves annually to reflect the production of coal from the reserves, updated geological models and mining recovery data, the tonnage contained in new lease areas acquired and estimated costs of production and sales prices. There are numerous factors and assumptions inherent in estimating the quantities and qualities of, and costs to mine, coal reserves, including many factors beyond our control, including the following:

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quality of the coal;

	•		geological and mining conditions, which may not be fully identified by available exploration data and/or may differ from our experiences in areas where we currently mine;

	•		the percentage of coal ultimately recoverable;

	•		the assumed effects of regulation, including the issuance of required permits, taxes, including severance and excise taxes and royalties, and other payments to governmental agencies;

	•		assumptions concerning the timing for the development of the reserves; and

	•		assumptions concerning equipment and productivity, future coal prices, operating costs, including for critical supplies such as fuel, tires and explosives, capital expenditures and development and reclamation costs.

As a result, estimates of the quantities and qualities of economically recoverable coal attributable to any particular group of properties, classifications of reserves based on risk of recovery, estimated cost of production, and estimates of future net cash flows expected from these properties as prepared by different engineers, or by the same engineers at different times, may vary materially due to changes in the above factors and assumptions. Actual production recovered from identified reserve areas and properties, and revenues and expenditures associated with our mining operations, may vary materially from estimates. Any inaccuracy in our estimates related to our reserves could result in decreased profitability from lower than expected revenues and/or higher than expected costs.

Increases in the costs of mining and other industrial supplies, including steel-based supplies, diesel fuel and rubber tires, or the inability to obtain a sufficient quantity of those supplies, could negatively affect our operating costs or disrupt or delay our production.

Our coal mining operations use significant amounts of steel, diesel fuel, explosives, rubber tires and other mining and industrial supplies. The cost of roof bolts we use in our underground mining operations depend on the price of scrap steel. We also use significant amounts of diesel fuel and tires for the trucks and other heavy machinery we use, particularly at our Black Thunder mining complex. If the prices of mining and other industrial supplies, particularly steel-based supplies, diesel fuel and rubber tires, increase, our operating costs could be negatively affected. In addition, if we are unable to procure these supplies, our coal mining operations may be disrupted or we could experience a delay or halt in our production.

Our ability to collect payments from our customers could be impaired if their creditworthiness deteriorates.

We have contracts to supply coal to energy trading and brokering companies under which they purchase the coal for their own account or resell the coal to end users. Our ability to receive payment for coal sold and delivered depends on the continued creditworthiness of our customers. If we determine that a customer is not creditworthy, we may not be required to deliver coal under the customer’s coal sales contract. If this occurs, we may decide to sell the customer’s coal on the spot market, which may be at prices lower than the contracted price, or we may be unable to sell the coal at all. Furthermore, the bankruptcy of any of our customers could materially and adversely affect our financial position. In addition, our customer base may change with deregulation as utilities sell their power plants to their non-regulated affiliates or third parties that may be less creditworthy, thereby increasing the risk we bear for customer payment default. These new power plant owners may have credit ratings that are below investment grade, or may become below investment grade after we enter into contracts with them. In addition, competition with other coal suppliers could force us to extend credit to customers and on terms that could increase the risk of payment default.

A defect in title or the loss of a leasehold interest in certain property could limit our ability to mine our coal reserves or result in significant unanticipated costs.

We conduct a significant part of our coal mining operations on properties that we lease. A title defect or the loss of a lease could adversely affect our ability to mine the associated coal reserves. We may not verify title to our leased properties or associated coal reserves until we have committed to developing those properties or coal reserves. We may not commit to develop property or coal reserves until we have obtained necessary permits and completed exploration. As such, the title to property that we intend to lease or coal reserves that we intend to mine may contain defects prohibiting our ability to conduct mining operations. Similarly, our leasehold interests may be subject to superior property rights of other third parties. In order to conduct our mining operations on properties where these defects exist, we may incur unanticipated costs. In addition, some leases require us to produce a minimum quantity of coal and require us to pay minimum production royalties. Our inability to satisfy those requirements may cause the leasehold interest to terminate.

The availability and reliability of transportation facilities and fluctuations in transportation costs could affect the demand for our coal or impair our ability to supply coal to our customers.

We depend upon barge, ship, rail, truck and belt transportation systems to deliver coal to our customers. Disruptions in transportation services due to weather-related problems, mechanical difficulties, strikes, lockouts, bottlenecks, and other events could impair our ability to supply coal to our customers. As we do not have long-term contracts with transportation providers to

ensure consistent and reliable service, decreased performance levels over longer periods of time could cause our customers to look to other sources for their coal needs. In addition, increases in transportation costs, including the price of gasoline and diesel fuel, could make coal a less competitive source of energy when compared to alternative fuels or could make coal produced in one region of the United States less competitive than coal produced in other regions of the United States or abroad. If we experience disruptions in our transportation services or if transportation costs increase significantly and we are unable to find alternative transportation providers, our coal mining operations may be disrupted, we could experience a delay or halt of production or our profitability could decrease significantly.

Our profitability depends upon the long-term coal supply agreements we have with our customers. Changes in purchasing patterns in the coal industry could make it difficult for us to extend our existing long-term coal supply agreements or to enter into new agreements in the future.

We sell a portion of our coal under long-term coal supply agreements, which we define as contracts with terms greater than one year. Under these arrangements, we fix the prices of coal shipped during the initial year and may adjust the prices in later years. As a result, at any given time the market prices for similar-quality coal may exceed the prices for coal shipped under these arrangements. Changes in the coal industry may cause some of our customers not to renew, extend or enter into new long-term coal supply agreements with us or to enter into agreements to purchase fewer tons of coal than in the past or on different terms or prices. In addition, uncertainty caused by federal and state regulations, including the Clean Air Act, could deter our customers from entering into long-term coal supply agreements.

Because we sell a portion of our coal production under long-term coal supply agreements, our ability to capitalize on more favorable market prices may be limited. Conversely, at any given time we are subject to fluctuations in market prices for the quantities of coal that we have produced but which we have not committed to sell. As described above under “A substantial or extended decline in coal prices could negatively affect our profitability and the value of our coal reserves,” the market prices for coal may be volatile and may depend upon factors beyond our control. Our profitability may be adversely affected if we are unable to sell uncommitted production at favorable prices or at all. For more information about our long-term coal supply agreements, you should see the section entitled “Long-Term Coal Supply Arrangements.”

The loss of, or significant reduction in, purchases by our largest customers could adversely affect our profitability.

For the year ended December 31, 2010, we derived approximately 25% of our total coal revenues from sales to our three largest customers and approximately 49% of our total coal revenues from sales to our ten largest customers. We expect to renew, extend or enter into new long-term coal supply agreements with those and other customers. However, we may be unsuccessful in obtaining long-term coal supply agreements with those customers, and those customers may discontinue purchasing coal from us. If any of those customers, particularly any of our three largest customers, was to significantly reduce the quantities of coal it purchases from us, or if we are unable to sell coal to those customers on terms as favorable to us as the terms under our current long-term coal supply agreements, our profitability could suffer significantly. We have limited protection during adverse economic conditions and may face economic penalties if we are unable to satisfy certain quality specifications under our long-term coal supply agreements.

Our long-term coal supply agreements typically contain force majeure provisions allowing the parties to temporarily suspend performance during specified events beyond their control. Most of our long-term coal supply agreements also contain provisions requiring us to deliver coal that satisfies certain quality specifications, such as heat value, sulfur content, ash content, hardness and ash fusion temperature. These provisions in our long-term coal supply agreements could result in negative economic consequences to us, including price adjustments, purchasing replacement coal in a higher-priced open market, the rejection of deliveries or, in the extreme, contract termination. Our profitability may be negatively affected if we are unable to seek protection during adverse economic conditions or if we incur financial or other economic penalties as a result of these provisions of our long-term supply agreements.

Failure to obtain or renew surety bonds on acceptable terms could affect our ability to secure reclamation and coal lease obligations and, therefore, our ability to mine or lease coal.

Federal and state laws require us to obtain surety bonds to secure performance or payment of certain long-term obligations, such as mine closure or reclamation costs, federal and state workers’ compensation costs, coal leases and other obligations. We may have difficulty procuring or maintaining our surety bonds. Our bond issuers may demand higher fees, additional collateral, including letters of credit or other terms less favorable to us upon those renewals. Because we are required by state and federal law to have these bonds in place before mining can commence or continue, or failure to maintain surety bonds, letters of credit or other guarantees or security arrangements would materially and adversely affect our ability to mine or lease coal. That failure could result from a variety of factors, including lack of availability, higher expense or unfavorable market terms, the exercise by third

party surety bond issuers of their right to refuse to renew the surety and restrictions on availability on collateral for current and future third party surety bond issuers under the terms of our financing arrangements.

Our ability to repay our remaining 6.75% senior notes may require funding from our parent company, Arch Coal, Inc.

Our parent company, Arch Coal, manages our cash transactions. Cash distributed by us to Arch Coal is generally recorded as a note receivable to us and payable by Arch Coal. As of December 31, 2010, we had a note receivable from Arch Coal in the amount of $1.5 billion. Our ability to redeem, or repay at maturity in 2013, our remaining 6.75% senior notes may be dependent on Arch Coal’s ability to pay to us a portion of their outstanding note receivable balance. In the event that Arch Coal would be unable to pay to us the amounts they owe to us, we may be unable to redeem, or repay at maturity in 2013, all or a portion of the outstanding 6.75% senior notes, and might have to seek alternative financing arrangements, which could impose additional restrictions on our operations and business.

Risks Related to Environmental, Other Regulations and Legislation

Extensive environmental regulations, including existing and potential future regulatory requirements relating to air emissions, affect our customers and could reduce the demand for coal as a fuel source and cause coal prices and sales of our coal to materially decline.

Coal contains impurities, including but not limited to sulfur, mercury, chlorine, carbon and other elements or compounds, many of which are released into the air when coal is burned. The operations of our customers are subject to extensive environmental regulation particularly with respect to air emissions. For example, the federal Clean Air Act and similar state and local laws extensively regulate the amount of sulfur dioxide, particulate matter, nitrogen oxides, and other compounds emitted into the air from electric power plants, which are the largest end-users of our coal. A series of more stringent requirements relating to particulate matter, ozone, haze, mercury, sulfur dioxide, nitrogen oxide and other air pollutants are expected to be proposed or become effective in coming years. In addition, concerted conservation efforts that result in reduced electricity consumption could cause coal prices and sales of our coal to materially decline.

Considerable uncertainty is associated with these air emissions initiatives. The content of regulatory requirements in the U.S. is in the process of being developed, and many new regulatory initiatives remain subject to review by federal or state agencies or the courts. Stringent air emissions limitations are either in place or are likely to be imposed in the short to medium term, and these limitations will likely require significant emissions control expenditures for many coal-fueled power plants. As a result, these power plants may switch to other fuels that generate fewer of these emissions or may install more effective pollution control equipment that reduces the need for low sulfur coal, possibly reducing future demand for coal and a reduced need to construct new coal-fueled power plants. The EIA’s expectations for the coal industry assume there will be a significant number of as yet unplanned coal-fired plants built in the future which may not occur. Any switching of fuel sources away from coal, closure of existing coal-fired plants, or reduced construction of new plants could have a material adverse effect on demand for and prices received for our coal. Alternatively, less stringent air emissions limitations, particularly related to sulfur, to the extent enacted could make low sulfur coal less attractive, which could also have a material adverse effect on the demand for and prices received for our coal.

You should see “Environmental and Other Regulatory Matters” for more information about the various governmental regulations affecting us.

Our failure to obtain and renew permits necessary for our mining operations could negatively affect our business.

Mining companies must obtain numerous permits that impose strict regulations on various environmental and operational matters in connection with coal mining. These include permits issued by various federal, state and local agencies and regulatory bodies. The permitting rules, and the interpretations of these rules, are complex, change frequently and are often subject to discretionary interpretations by the regulators, all of which may make compliance more difficult or impractical, and may possibly preclude the continuance of ongoing operations or the development of future mining operations. The public, including non-governmental organizations, anti-mining groups and individuals, have certain statutory rights to comment upon and submit objections to requested permits and environmental impact statements prepared in connection with applicable regulatory processes, and otherwise engage in the permitting process, including bringing citizens’ lawsuits to challenge the issuance of permits, the validity of environmental impact statements or performance of mining activities. Accordingly, required permits may not be issued or renewed in a timely fashion or at all, or permits issued or renewed may be conditioned in a manner that may restrict our ability to efficiently and economically conduct our mining activities, any of which would materially reduce our production, cash flow and profitability.

Federal or state regulatory agencies have the authority to order certain of our mines to be temporarily or permanently closed under certain circumstances, which could materially and adversely affect our ability to meet our customers’ demands.

Federal or state regulatory agencies have the authority under certain circumstances following significant health and safety incidents, such as fatalities, to order a mine to be temporarily or permanently closed. If this occurred, we may be required to incur capital expenditures to re-open the mine. In the event that these agencies order the closing of our mines, our coal sales contracts generally permit us to issue force majeure notices which suspend our obligations to deliver coal under these contracts. However, our customers may challenge our issuances of force majeure notices. If these challenges are successful, we may have to purchase coal from third-party sources, if it is available, to fulfill these obligations, incur capital expenditures to re-open the mines and/or negotiate settlements with the customers, which may include price reductions, the reduction of commitments or the extension of

time for delivery or terminate customers’ contracts. Any of these actions could have a material adverse effect on our business and results of operations.

Extensive environmental regulations impose significant costs on our mining operations, and future regulations could materially increase those costs or limit our ability to produce and sell coal.

The coal mining industry is subject to increasingly strict regulation by federal, state and local authorities with respect to environmental matters such as:

	•		limitations on land use;

	•		mine permitting and licensing requirements;

	•		reclamation and restoration of mining properties after mining is completed;

	•		management of materials generated by mining operations;

	•		the storage, treatment and disposal of wastes;

	•		remediation of contaminated soil and groundwater;

	•		air quality standards;

	•		water pollution;

	•		protection of human health, plant-life and wildlife, including endangered or threatened species;

	•		protection of wetlands;

	•		the discharge of materials into the environment;

	•		the effects of mining on surface water and groundwater quality and availability; and

	•		the management of electrical equipment containing polychlorinated biphenyls.

The costs, liabilities and requirements associated with the laws and regulations related to these and other environmental matters may be costly and time-consuming and may delay commencement or continuation of exploration or production operations. We cannot assure you that we have been or will be at all times in compliance with the applicable laws and regulations. Failure to comply with these laws and regulations may result in the assessment of administrative, civil and criminal penalties, the imposition of cleanup and site restoration costs and liens, the issuance of injunctions to limit or cease operations, the suspension or revocation of permits and other enforcement measures that could have the effect of limiting production from our operations. We may incur material costs and liabilities resulting from claims for damages to property or injury to persons arising from our operations. If we are pursued for sanctions, costs and liabilities in respect of these matters, our mining operations and, as a result, our profitability could be materially and adversely affected.

New legislation or administrative regulations or new judicial interpretations or administrative enforcement of existing laws and regulations, including proposals related to the protection of the environment that would further regulate and tax the coal industry, may also require us to change operations significantly or incur increased costs. Such changes could have a material adverse effect on our financial condition and results of operations. You should see the section entitled “Environmental and Other Regulatory Matters” for more information about the various governmental regulations affecting us.

If the assumptions underlying our estimates of reclamation and mine closure obligations are inaccurate, our costs could be greater than anticipated.

SMCRA and counterpart state laws and regulations establish operational, reclamation and closure standards for all aspects of surface mining, as well as most aspects of underground mining. We base our estimates of reclamation and mine closure liabilities on permit requirements, engineering studies and our engineering expertise related to these requirements. Our management and engineers periodically review these estimates. The estimates can change significantly if actual costs vary from our original assumptions or if governmental regulations change significantly. We are required to record new obligations as liabilities at fair value under generally accepted accounting principles. In estimating fair value, we considered the estimated current costs of reclamation and mine closure and applied inflation rates and a third-party profit, as required. The third-party profit is an estimate of the approximate markup that would be charged by contractors for work performed on our behalf. The resulting estimated reclamation and mine closure obligations could change significantly if actual amounts change significantly from our assumptions, which could have a material adverse effect on our results of operations and financial condition.

Our operations may impact the environment or cause exposure to hazardous substances, and our properties may have environmental contamination, which could result in material liabilities to us.

Our operations currently use hazardous materials and generate limited quantities of hazardous wastes from time to time. We could become subject to claims for toxic torts, natural resource damages and other damages as well as for the investigation and clean up of soil, surface water, groundwater, and other media. Such claims may arise, for example, out of conditions at sites that we currently own or operate, as well as at sites that we previously owned or operated, or may acquire. Our liability for such claims

may be joint and several, so that we may be held responsible for more than our share of the contamination or other damages, or even for the entire share.

We maintain extensive coal refuse areas and slurry impoundments at a number of our mining complexes. Such areas and impoundments are subject to extensive regulation. Slurry impoundments have been known to fail, releasing large volumes of coal slurry into the surrounding environment. Structural failure of an impoundment can result in extensive damage to the environment and natural resources, such as bodies of water that the coal slurry reaches, as well as liability for related personal injuries and property damages, and injuries to wildlife. Some of our impoundments overlie mined out areas, which can pose a heightened risk of failure and of damages arising out of failure. If one of our impoundments were to fail, we could be subject to substantial claims for the resulting environmental contamination and associated liability, as well as for fines and penalties.

Drainage flowing from or caused by mining activities can be acidic with elevated levels of dissolved metals, a condition referred to as “acid mine drainage,” which we refer to as AMD. The treating of AMD can be costly. Although we do not currently face material costs associated with AMD, it is possible that we could incur significant costs in the future.

These and other similar unforeseen impacts that our operations may have on the environment, as well as exposures to hazardous substances or wastes associated with our operations, could result in costs and liabilities that could materially and adversely affect us.

Changes in the legal and regulatory environment, particularly in light of developments in 2010, could complicate or limit our business activities, increase our operating costs or result in litigation.

The conduct of our businesses is subject to various laws and regulations administered by federal, state and local governmental agencies in the United States. These laws and regulations may change, sometimes dramatically, as a result of political, economic or social events or in response to significant events. Certain recent developments particularly may cause changes in the legal and regulatory environment in which we operate and may impact our results or increase our costs or liabilities. Such legal and regulatory environment changes may include changes in: the processes for obtaining or renewing permits; costs associated with providing healthcare benefits to employees; health and safety standards; accounting standards; taxation requirements; and competition laws.

In response to the April 2010 explosion at Massey Energy Company’s Upper Big Branch Mine and the ensuing tragedy, we expect that safety matters pertaining to underground coal mining operations will be the topic of new legislation and regulation, as well as the subject of heightened enforcement efforts. For example, federal and West Virginia state authorities have announced special inspections of coal mines to evaluate several safety concerns, including the accumulation of coal dust and the proper ventilation of gases such as methane. In addition, both federal and West Virginia state authorities have announced that they are considering changes to mine safety rules and regulations which could potentially result in additional or enhanced required safety equipment, more frequent mine inspections, stricter and more thorough enforcement practices and enhanced reporting requirements. Any new environmental, health and safety requirements may increase the costs associated with obtaining or maintain permits necessary to perform our mining operations or otherwise may prevent, delay or reduce our planned production, any of which could adversely affect our financial condition, results of operations and cash flows.

Further, mining companies are entitled a tax deduction for percentage depletion, which may allow for depletion deductions in excess of the basis in the mineral reserves. The deduction is currently being reviewed by the federal government for repeal. If repealed, the inability to take a tax deduction for percentage depletion could have a material impact on our financial condition, results of operations, cash flows and future tax payments.

ITEM 1B. UNRESOLVED STAFF COMMENTS.

None.

ITEM 2. PROPERTIES.

Our Properties

General

At December 31, 2010, we owned or controlled primarily through long-term leases approximately 107,812 acres of coal land in Wyoming, 64,673 acres of coal land in Utah, 21,798 acres of coal land in New Mexico and 18,521 acres of coal land in Colorado. We lease a significant portion of our coal land from Arch Coal. Arch Coal leases a portion of that property from the federal government and from various state governments. Certain of our loadout facilities are located on properties held under leases which expire at varying dates over the next 30 years. Most of the leases contain options to renew. Our remaining loadout facilities are located on property owned by Arch Coal or for which we have a special use permit.

Our Coal Reserves

We estimate that we owned or controlled approximately 2.3 billion tons of proven and probable recoverable reserves at December 31, 2010. We had approximately 1.24 billion tons of reserves under lease with Arch Coal at December 31, 2010. Our coal reserve estimates at December 31, 2010 were prepared by our engineers and geologists and reviewed by Weir International, Inc., a mining and geological consultant. Our coal reserve estimates are based on data obtained from our drilling activities and other available geologic data. Our coal reserve estimates are periodically updated to reflect past coal production and other geologic and mining data. Acquisitions or sales of coal properties will also change these estimates. Changes in mining methods or the utilization of new technologies may increase or decrease the recovery basis for a coal seam.

Our coal reserve estimates include reserves that can be economically and legally extracted or produced at the time of their determination. In determining whether our reserves meet this standard, we take into account, among other things, our potential inability to obtain a mining permit, the possible necessity of revising a mining plan, changes in estimated future costs, changes in future cash flows caused by changes in costs required to be incurred to meet regulatory requirements and obtaining mining permits, variations in quantity and quality of coal, and varying levels of demand and their effects on selling prices. We use various assumptions in preparing our estimates of our coal reserves. You should see “Inaccuracies in our estimates of our coal reserves could result in decreased profitability from lower than expected revenues or higher than expected costs” contained under the heading “Risk Factors.”

The following tables present our estimated assigned and unassigned recoverable coal reserves at December 31, 2010:

Total Assigned Reserves

(Tons in millions)


	Total												As
	Assigned						Sulfur Content						Received						Mining Method				Past Reserve
	Recoverable						(lbs. per million Btus)						Btus		Reserve Control						Under-		Estimates
	Reserves		Proven		Probable		<1.2		1.2-2.5		>2.5		per lb.(1)		Leased		Owned		Surface		ground		2008		2009
Wyoming		1,605		1,581		24		1,514		91		—		8,852		1,592		13		1,605		—		1,476		1,733
Utah		84		50		34		74		9		1		11,337		83		1		—		84		89		105
Colorado		64		52		12		64		—		—		11,278		64		—		—		64		71		75

Total		1,753		1,683		70		1,652		100		1		9,060		1,739		14		1,605		148		1,636		1,913


(1)		As received Btus per lb. includes the weight of moisture in the coal on an as sold basis.

Total Unassigned Reserves

(Tons in millions)


	Total
	Unassigned						Sulfur Content
	Recoverable						(lbs. per million Btus)						As Received		Reserve Control				Mining Method
	Reserves		Proven		Probable		<1.2		1.2-2.5		>2.5		Btus per lb.(1)		Leased		Owned		Surface		Underground
Wyoming		489		405		84		440		49		—		9,567		396		93		314		175
Utah		35		14		21		35		—		—		10,799		34		1		—		35
Colorado		45		37		8		45		—		—		11,384		45		—		—		45

Total		569		456		113		520		49		—		9,785		475		94		314		255


(1)		As received Btus per lb. includes the weight of moisture in the coal on an as sold basis.

Federal and state legislation controlling air pollution affects the demand for certain types of coal by limiting the amount of sulfur dioxide which may be emitted as a result of fuel combustion and encourages a greater demand for low-sulfur coal. All of our identified coal reserves have been subject to preliminary coal seam analysis to test sulfur content. Of these reserves, approximately 93.5% consist of compliance coal, or coal which emits 1.2 pounds or less of sulfur dioxide per million Btus upon combustion, while an additional 3.2% could be sold as low-sulfur coal.

The carrying cost of our coal reserves at December 31, 2010 was $346.3 million.

Reserve Acquisition Process

A significant portion of the coal we control in the western United States was acquired by Arch Coal through the LBA process. Under this process, before a mining company can obtain new coal reserves, the coal tract must be nominated for lease, and the company must win the lease through a competitive bidding process. The LBA process can last anywhere from two to five years from the time the coal tract is nominated to the time a final bid is accepted by the BLM. After the LBA is awarded, the company then conducts the necessary testing to determine what amount can be classified as reserves.

To initiate the LBA process, companies wanting to acquire additional coal must file an application with the BLM’s state office indicating interest in a specific coal tract. The BLM reviews the initial application to determine whether the application conforms to existing land-use plans for that particular tract of land and that the application would provide for maximum coal recovery. The application is further reviewed by a regional coal team at a public meeting. Based on a review of the available information and public comment, the regional coal team will make a recommendation to the BLM whether to continue, modify or reject the application.

If the BLM determines to continue the application, the company that submitted the application will pay for a BLM-directed environmental analysis or an environmental impact statement to be completed. This analysis or impact statement is subject to publication and public comment. The BLM may consult with other governmental agencies during this process, including state and federal agencies, surface management agencies, Native American tribes or bands, the U.S. Department of Justice or others as needed. The public comment period for an analysis or impact statement typically occurs over a 60-day period.

After the environmental analysis or environmental impact statement has been issued and a recommendation has been published that supports the lease sale of the LBA tract, the BLM schedules a public competitive lease sale. The BLM prepares an internal estimate of the fair market value of the coal that is based on its economic analysis and comparable sales analysis. Prior to the lease sale, companies interested in acquiring the lease must send sealed bids to the BLM. The bid amounts for the lease are payable in five annual installments, with the first 20% installment due when the mining operator submits its initial bid for an LBA. Before the lease is approved by the BLM, the company must first furnish to the BLM an initial rental payment for the first year of rent along with either a bond for the next 20% annual installment payment for the bid amount, or an application for history of timely payment, in which case the BLM may waive the bond requirement if the company successfully meets all the qualifications of a timely payor. The bids are opened at the lease sale. If the BLM decides to grant a lease, the lease is awarded to the company that submitted the highest total bid meeting or exceeding the BLM’s fair market value estimate, which is not published. The BLM, however, is not required to grant a lease even if it determines that a bid meeting or exceeding the fair market value of the coal has been submitted. The winning bidder must also submit a report setting forth the nature and extent of its coal holdings to the U.S. Department of Justice for a 30-day antitrust review of the lease. If the successful bidder was not the initial applicant, the BLM will refund the initial applicant certain fees it paid in connection with the application process, for example the fees associated with

the environmental analysis or environmental impact statement, and the winning bidder will bear those costs. Coal won through the LBA process and subject to federal leases are administered by the U.S. Department of Interior under the Federal Coal Leasing Amendment Act of 1976. In addition, we occasionally add small coal tracts adjacent to our existing LBAs through an agreed upon lease modification with the BLM. Once the BLM has issued a lease, the company must also complete the permitting process before it can mine the coal. You should see the section entitled “Environmental and Other Regulatory Matters.”

Most of the federal coal leases governing the property we control have an initial term of 20 years and are renewable for subsequent 10-year periods and for so long thereafter as coal is produced in commercial quantities. These leases require diligent development within the first ten years of the lease award with a required coal extraction of 1.0% of the total coal under the lease by the end of that 10-year period. At the end of the 10-year development period, the lessee is required to maintain continuous operations, as defined in the applicable leasing regulations. In certain cases a lessee may combine contiguous leases into a logical mining unit, which we refer to as an LMU. This allows the production of coal from any of the leases within the LMU to be used to meet the continuous operation requirements for the entire LMU. Some of our mines are also subject to coal leases with applicable state regulatory agencies and have different terms and conditions that we must adhere to in a similar way to our federal leases. Under these federal and state leases, if the leased coal is not diligently developed during the initial 10-year development period or if certain other terms of the leases are not complied with, including the requirement to produce a minimum quantity of coal or pay a minimum production royalty, if applicable, the BLM or the applicable state regulatory agency can terminate the lease prior to the expiration of its term.

Title to Coal Property

Title to coal properties held by lessors or grantors to us and our subsidiaries and the boundaries of properties are normally verified at the time of leasing or acquisition. However, in cases involving less significant properties and consistent with industry practices, title and boundaries are not completely verified until such time as our independent operating subsidiaries prepare to mine such reserves. If defects in title or boundaries of undeveloped reserves are discovered in the future, control of and the right to mine such reserves could be adversely affected. You should see “A defect in title or the loss of a leasehold interest in certain property could limit our ability to mine our coal reserves or result in significant unanticipated costs” contained under the heading “Risk Factors” for more information.

At December 31, 2010, approximately 4.6% of our coal reserves were held in fee, with the balance controlled by leases, most of which do not expire until the exhaustion of mineable and merchantable coal. Under current mining plans, substantially all reported leased reserves will be mined out within the period of existing leases or within the time period of assured lease renewals. Royalties are paid to lessors either as a fixed price per ton or as a percentage of the gross sales price of the mined coal. The majority of the significant leases are on a percentage royalty basis. In some cases, a payment is required, payable either at the time of execution of the lease or in annual installments. In most cases, the prepaid royalty amount is applied to reduce future production royalties.

From time to time, lessors or sublessors of land leased by our subsidiaries have sought to terminate such leases on the basis that such subsidiaries have failed to comply with the financial terms of the leases or that the mining and related operations conducted by such subsidiaries are not authorized by the leases. Some of these allegations relate to leases upon which we conduct operations material to our consolidated financial position, results of operations and liquidity, but we do not believe any pending claims by such lessors or sublessors have merit or will result in the termination of any material lease or sublease.

ITEM 3. LEGAL PROCEEDINGS.

We are involved in various claims and legal actions arising in the ordinary course of business, including employee injury claims. After conferring with counsel, it is the opinion of management that the ultimate resolution of these claims, to the extent not previously provided for, will not have a material adverse effect on our consolidated financial condition, results of operations or liquidity.

ITEM 4. RESERVED

Mine Safety and Health Administration Safety Data

We believe that we have some of the safest producing operations in the world. Safety is a core value at our parent company, Arch Coal, and at each of its subsidiary operations. We have in place a comprehensive safety program that includes extensive health & safety training for all employees, site inspections, emergency response preparedness, crisis communications training, incident investigation, regulatory compliance training and process auditing, as well as an open dialogue between all levels of employees. The goals of our processes are to eliminate exposure to hazards in the workplace, ensure that we comply with all mine safety regulations, and support regulatory and industry efforts to improve the health and safety of our employees along with the industry as a whole.

Under the Dodd-Frank Wall Street Reform and Consumer Protection Act passed in 2010, each operator of a coal or other mine is required to include certain mine safety results in its periodic reports filed with the Securities and Exchange Commission. The operation of our mines is subject to regulation by the federal Mine Safety and Health Administration (“MSHA”) under the Federal Mine Safety and Health Act of 1977 (the “Mine Act”). Below we present the following items regarding certain mine safety and health matters, broken down by mining complex owned and operated by Arch Western or our subsidiaries, for the three-month and twelve-month periods ended December 31, 2010:

	•		Section 104 Citations: Total number of violations of mandatory health or safety standards that could significantly and substantially contribute to the cause and effect of a coal or other mine safety or health hazard under section 104 of the Mine Act for which we have received a citation from MSHA;

	•		Section 104(b) Orders: Total number of orders issued under section 104(b) of the Mine Act;

	•		Section 104(d) Citations/Orders: Total number of citations and orders for unwarrantable failure of the mine operator to comply with mandatory health or safety standards under Section 104(d) of the Mine Act;

	•		Section 107(a) Orders: Total number of imminent danger orders issued under section 107(a) of the Mine Act; and

	•		Total Dollar Value of Proposed MSHA Assessments: Total dollar value of proposed assessments from MSHA under the Mine Act.

Three-Month Period Ended December 31, 2010


									Total Dollar Value of
	Section 104		Section 104(b)		Section 10k4(d)		Section 107(a)		Proposed MSHA
Mining complex(1)	Citations		Orders		Citations/Orders		Orders		Assessments
									(In thousands)(2)
Power River Basin:
Black Thunder		—		—		—		—	$	0
Coal Creek		—		—		—		—	$	0
Western Bituminous:
Arch of Wyoming		—		—		—		—	$	0.1
Dugout Canyon		17		1		3		1	$	0
Skyline		8		—		1		—	$	10.5
Sufco		6		—		2		—	$	8.3
West Elk		10		—		1		—	$	22.9


1)		MSHA assigns an identification number to each coal mine and may or may not assign separate identification numbers to related facilities such as preparation plants. We are providing the information in this table by mining complex rather than MSHA identification number because we believe this format will be more useful to investors than providing information based on MSHA identification numbers. For descriptions of each of these mining operations please refer to the descriptions under Item 1. Business, in Part I.

2)		Amounts included under the heading “Total Dollar Value of Proposed MSHA Assessments” are the total dollar amounts for proposed assessments received from MSHA on or before February 1, 2011 for citations and orders occurring during the three-month period ended December 31, 2010.

For the three-month period ended December 31, 2010, none of our mining complexes received written notice from MSHA of (i) a flagrant violation under section 110(b)(2) of the Mine Act; (ii) a pattern of violations of mandatory health or safety standards that are of such nature as could have significantly and substantially contributed to the cause and effect of coal or other mine health or safety hazards under section 104(e) of the Mine Act; or (iii) the potential to have such a pattern. For the three-month period ended December 31, 2010, none of our mining complexes experienced a mining-related fatality.

Twelve-Month Period Ended December 31, 2010


									Total Dollar Value of
	Section 104		Section 104(b)		Section 104(d)		Section 107(a)		Proposed MSHA
Mining complex(1)	Citations		Orders		Citations/Orders		Orders		Assessments
									(In thousands)(2)
Power River Basin:
Black Thunder		8		—		—		—	$	19.5
Coal Creek		—		—		—		—	$	2.2
Western Bituminous:
Arch of Wyoming		2		—		—		—	$	1.4
Dugout Canyon		52		2		3		1	$	90.1
Skyline		30		—		1		—	$	42.2
Sufco		37		—		6		1	$	94.4
West Elk		50		—		1		3	$	332.4


1)		MSHA assigns an identification number to each coal mine and may or may not assign separate identification numbers to related facilities such as preparation plants. We are providing the information in this table by mining complex rather than MSHA identification number because we believe this format will be more useful to investors than providing information based on MSHA identification numbers. For descriptions of each of these mining operations please refer to the descriptions under Item 1. Business, in Part I.

2)		Amounts included under the heading “Total Dollar Value of Proposed MSHA Assessments” are the total dollar amounts for proposed assessments received from MSHA on or before February 1, 2011 for citations and orders occurring during the twelve-month period ended December 31, 2010.

For the twelve-month period ended December 31, 2010 none of our mining complexes received written notice from MSHA of (i) a flagrant violation under section 110(b)(2) of the Mine Act; (ii) a pattern of violations of mandatory health or safety standards that are of such nature as could have significantly and substantially contributed to the cause and effect of coal or other mine health or safety hazards under section 104(e) of the Mine Act; or (iii) the potential to have such a pattern. During the twelve-month period ended December 31, 2010, none of our mining complexes experienced a mining-related fatality.

As of December 31, 2010, we had a total of 49 matters pending before the Federal Mine Safety and Health Review Commission. This includes legal actions that were initiated prior to the twelve-month period ended December 31, 2010 and which do not necessarily relate to the citations, orders or proposed assessments issued by MSHA during such twelve-month period.

In evaluating the above information regarding mine safety and health, investors should take into account factors such as: (i) the number of citations and orders will vary depending on the size of a coal mine, (ii) the number of citations issued will vary from inspector to inspector and mine to mine, and (iii) citations and orders can be contested and appealed, and in that process are often reduced in severity and amount, and are sometimes dismissed.

PART II

ITEM 5. MARKET FOR REGISTRANT’S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES.

There is no market for our common equity.

ITEM 6. SELECTED FINANCIAL DATA.


	Year Ended December 31
	2010⁽¹⁾			2009⁽²⁾		2008			2007			2006⁽³⁾
	(Amounts in thousands, except per ton data)
Statement of Operations Data:
Coal sales revenue	$	2,048,287		$	1,651,389	$	1,758,008		$	1,541,066		$	1,491,362
Income from operations		134,349			39,310		180,392			197,271			314,263
Net income		118,403			18,276		188,705			221,661			315,915
Balance Sheet Data:
Cash and cash equivalents	$	79,817		$	6,819	$	2,851		$	248		$	186
Receivable from Arch Coal, Inc.		1,493,181			1,541,243		1,528,068			1,427,833			1,152,102
Total assets		3,246,630			3,307,913		3,105,084			2,852,187			2,557,772
Total debt, including note payable to Arch Coal		733,522			1,004,234		1,021,819			1,032,473			958,881
Redeemable membership interests		10,444			8,962		8,765			8,000			6,934
Non-redeemable membership interests		1,836,070			1,706,710		1,495,613			1,330,202			1,097,067
Cash Flow Data:
Cash provided by operating activities	$	438,376		$	178,119	$	396,582		$	324,764		$	539,666
Depreciation, depletion and amortization		167,260			159,755		155,400			136,927			119,014
Amortization of acquired sales contracts, net		35,606			19,623		(705	)		(1,633	)		(10,742	)
Capital expenditures		102,612			125,454		286,607			147,423			260,368
Repayments of long-term debt, including redemption premium		(505,627	)		—		—			—			—
Operating Data:
Tons sold		143,953			107,649		120,361			115,743			113,759
Tons produced		144,101			108,213		119,494			115,841			114,928
Average sales price per ton	$	14.23		$	15.34	$	14.61		$	13.31		$	13.11


⁽¹⁾		On September 8, 2010, we redeemed $500.0 million aggregate principal amount of the outstanding 6.75% senior notes due in 2013 at a redemption price of 101.125%. We funded this redemption with cash transferred from Arch Coal in the form of a loan of $225.0 million and a repayment of a portion of the balance receivable from Arch Coal. We recognized a loss on the redemption of $6.8 million, including the payment of $5.6 million redemption premium, the write-off of $3.3 million of unamortized debt financing costs, partially offset by the write-off of $2.1 million of the original issue premium on the senior notes.

⁽²⁾		On October 1, 2009, Arch Coal acquired the Jacobs Ranch mining operations for a purchase price of $768.8 million. The acquisition included approximately 345 million tons of coal reserves located adjacent to our Black Thunder mining complex. Arch Coal contributed the acquired employees, inventories and supply parts, equipment and other personal property to us, which we immediately merged with our Black Thunder mining operations. We lease the related coal reserves of approximately 345 million tons from a subsidiary of Arch Coal.

⁽³⁾		On October 27, 2005, we conducted a precautionary evacuation of our West Elk mine after we detected elevated readings of combustion-related gases in an area of the mine where we had completed mining activities but had not yet removed final longwall equipment. We estimate that the idling resulted in $30.0 million of lost profits during the first quarter of 2006, in addition to the effect of the idling and fire-fighting costs incurred during the fourth quarter of 2005 of $33.3 million. We recognized insurance recoveries related to the event of $41.9 million during the year ended December 31, 2006.

ITEM 7. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

Overview

We are a subsidiary of Arch Coal, Inc., one of the world’s largest coal producers by volume. We sell substantially all of our coal to power plants and industrial facilities. Our two reportable business segments are based on the low-sulfur U.S. coal producing regions in which we operate — the Powder River Basin and the Western Bituminous region. These geographically distinct areas are characterized by geology, coal transportation routes to consumers, regulatory environments and coal quality. These regional similarities have caused market and contract pricing environments to develop by coal region and form the basis for the segmentation of our operations.

The Powder River Basin is located in northeastern Wyoming and southeastern Montana. The coal we mine from surface operations in this region is very low in sulfur content and has a low heat value compared to the other regions in which we operate. The price of Powder River Basin coal is generally less than that of coal produced in other regions because Powder River Basin coal exists in greater abundance, is easier to mine and thus has a lower cost of production. In addition, Powder River Basin coal is generally lower in heat content, which requires some electric power generation facilities to blend it with higher Btu coal or retrofit some existing coal plants to accommodate lower Btu coal. The Western Bituminous region includes Colorado, Utah and southern Wyoming. Coal we mine from underground and surface mines in this region typically is low in sulfur content and varies in heat content.

Growth in domestic and global coal demand combined with coal supply constraints in many traditional coal exporting countries benefited coal markets during 2010. U.S. power generation increased more than 4% in 2010, in response to improving economic conditions, as well as favorable weather trends across most regions of the U.S. We estimate that U.S. steam coal consumption grew by 5.6% in 2010, driven by the increase in power generation as well as improving industrial demand. Growth in global coal demand, coupled with weather and infrastructure-driven supply constraints in major coal exporting countries, has also positively influenced the U.S. coal markets. As a result, U.S. coal exports reached 81 million tons in 2010, a 35% increase over 2009.

U.S. coal production overall increased 10 million tons in 2010, but declined by 12 millio+n tons in Central Appalachia. Looking ahead, we expect continued supply pressures in Central Appalachia to create opportunities for other coal basins, particularly the Powder River Basin. Coal production in the Powder River Basin increased 11 million tons in 2010, and forward prices for Powder River Basin coal have improved since the beginning of 2010.

We expect growing global demand and continuing supply constraints in traditional coal exporting countries to continue to fuel seaborne coal markets for steam coal from the U.S.

In January 2011, Arch Coal took steps towards accomplishing a strategic objective of expanding sales of Powder River Basin coal into the Asia-Pacific region. Arch Coal acquired a 38% interest in Millennium Bulk Terminals-Longview, LLC (“Millennium Terminal”), which owns a brownfield bulk commodity terminal on the Columbia River near Longview, Washington. Millennium Terminal continues to work on obtaining the required approvals and necessary permits to complete dredging and other upgrades to enable coal, alumina and cementious material shipments through the terminal. Arch will control 38% of the terminal’s throughput and storage capacity to facilitate export shipments of coal off the west coast of the United States. The terminal is served by the Union Pacific and Burlington Northern Santa Fe railroads, which will provide us access to export markets from our Powder River Basin and Western Bituminous regions. Arch Coal also entered into an agreement with Canadian Crown Corporation Ridley Terminals Inc. (“Ridley Terminal”), a coal and other bulk commodity marine terminal located near Prince Rupert, British Columbia, which provides us with direct, immediate access to the growing seaborne thermal market. The five-year agreement will give us throughput capacity at the terminal of up to 2 million metric tons of coal for 2011 and up to 2.5 million metric tons of coal annually for 2012 through 2015. Ridley Terminal has the capacity to load up to 12 million metric tons of coal annually, with expansion plans that could double the facility’s capacity by 2015.

Items Affecting Comparability of Reported Results

The comparability of our operating results for the years ended December 31, 2010, 2009 and 2008 is affected by the following significant items:

Dugout Canyon production suspensions — We temporarily suspended production at our Dugout Canyon mine in Carbon County, Utah, on April 29, 2010 after an increase in carbon monoxide levels resulted from a heating event in a previously mined area. After permanently sealing the area, we resumed full coal production on May 21, 2010. On June 22, 2010, an ignition event at our longwall resulted in a second evacuation of all underground employees at the mine. All employees were safely evacuated in both events. The resumption of mining required us to render the mine’s atmosphere inert, ventilate the longwall area, determine the cause of the ignition, implement preventive measures, and secure an MSHA-approved longwall ventilation plan. We restarted the longwall system on September 9, 2010, and resumed production at normalized levels by the end of September. As a result of the outages in the second and third quarters, the Dugout Canyon mine incurred a loss of $29.3 million for the year ended December 31, 2010. We have provided additional information about the performance of our operating segments under the heading “Operating segment results”.

Redemption of Senior Notes —On September 8, 2010 we redeemed $500.0 million aggregate principal amount of our outstanding 6.75% senior notes due in 2013 at a redemption price of 101.125%. We recognized a loss on the redemption of $6.8 million, including the payment of the $5.6 million redemption premium and the write-off of $3.3 million of unamortized debt financing costs, partially offset by the write-off of $2.1 million of the original issue premium on the 6.75% senior notes.

Acquisition of Jacobs Ranch mining operations — On October 1, 2009, Arch Coal acquired the Jacobs Ranch mining operations for a purchase price of $768.8 million. The acquisition included approximately 345 million tons of coal reserves located adjacent to our Black Thunder mining complex. Arch Coal contributed the acquired employees, inventories and supply parts, equipment and other personal property to us, which we immediately merged with our Black Thunder mining operations. We lease the coal reserves from a subsidiary of Arch Coal and have achieved significant operating efficiencies by combining the two operations, including operational cost savings, administrative cost reductions and coal-blending optimization.

Results of Operations

Year Ended December 31, 2010 Compared to Year Ended December 31, 2009

Summary. Our improved results for the year ended December 31, 2010 when compared to the year ended December 31, 2009 were generated from increased sales volumes and lower production costs.

Revenues. The following table summarizes information about coal sales during the year ended December 31, 2010 and compares it with the information for the year ended December 31, 2009:


	Year Ended December 31				Increase (Decrease)
	2010		2009		Amount			%
	(Amounts in thousands, except per ton data and percentages)
Coal sales	$	2,048,287	$	1,651,389	$	396,898			24.0	%
Tons sold		143,953		107,649		36,304			33.7	%
Coal sales realization per ton sold	$	14.23	$	15.34	$	(1.11	)		(7.2	)%

Coal sales increased in 2010 from 2009, primarily due to an increase in tons sold in the Powder River Basin region, resulting from the acquisition of the Jacobs Ranch mining complex at the beginning of the fourth quarter of 2009. Our average coal sales realization per ton was lower in 2010, due to the impact of changes in regional mix on our average selling price and lower pricing in the Powder River Basin. We have provided more information about the tons sold and the coal sales realizations per ton by operating segment under the heading “Operating segment results”.

Costs, expenses and other. The following table summarizes costs, expenses and other components of operating income for the year ended December 31, 2010 and compares it with the information for the year ended December 31, 2009:


							Increase (Decrease)
	Year Ended December 31						in Net Income
	2010			2009			$			%
	(Dollars in thousands)
Cost of coal sales	$	1,679,872		$	1,398,663		$	(281,209	)		(20.1	)%
Depreciation, depletion and amortization		167,260			159,755			(7,505	)		(4.7	)
Amortization of acquired sales contracts, net		35,606			19,623			(15,983	)		(81.5	)
Selling, general and administrative expenses		35,989			44,513			8,524			19.1
Other operating income, net		(4,789	)		(10,475	)		(5,686	)		(54.3	)

Total	$	1,913,938		$	1,612,079		$	(301,859	)		(18.7	)%

Cost of coal sales. Our cost of coal sales increased in 2010 from 2009 primarily due to the higher sales volumes discussed above, partially offset by the impact of a lower average cost per-ton sold, due to the impact of the changes in regional mix as well as lower per-ton production costs in both regions. We have provided more information about our operating segments under the heading “Operating segment results”.

Depreciation, depletion and amortization. When compared with 2009, higher depreciation and amortization costs in 2010 resulted primarily from the impact of the acquisition of the Jacobs Ranch mining complex in the fourth quarter of 2009.

Amortization of acquired sales contracts, net. Arch Coal acquired both above- and below-market sales contracts with a net fair value of $58.4 million with the Jacobs Ranch mining operation. The sales contracts were not contributed to us, however, the amortization of these acquired sales contracts is reflected in our results. The fair values of acquired sales contracts are amortized over the tons of coal shipped during the term of the contracts.

Selling, general and administrative expenses. Selling, general and administrative expenses represent expenses allocated to us from Arch Coal. Expenses are allocated based on Arch Coal’s best estimates of proportional or incremental costs, whichever is more representative of costs incurred by Arch Coal on our behalf. Costs allocated during 2009 include acquisition costs related to Arch Coal’s purchase of the Jacobs Ranch mining complex.

Other operating income, net. The net decrease is primarily the result of a decrease in income from contract settlements.

Operating segment results. The following table shows results by operating segment for the year ended December 31, 2010 and compares it with the information for the year ended December 31, 2009:


	Year Ended December 31				Increase (Decrease)
	2010		2009		Amount			%
	(Amounts in thousands, except per ton data and percentages)
Powder River Basin
Tons sold		127,645		90,956		36,689			40.3	%
Coal sales realization per ton sold(1)	$	11.76	$	12.11	$	(0.35	)		(2.9	)%
Operating margin per ton sold(2)	$	0.83	$	0.47	$	0.36			76.6	%
Western Bituminous
Tons sold		16,308		16,693		(385	)		(2.3	)%
Coal sales realization per ton sold(1)	$	29.61	$	29.11	$	0.50			1.7	%
Operating margin per ton sold(2)	$	3.36	$	1.66	$	1.70			102.4	%


(1)		Coal sales prices per ton exclude certain transportation costs that we pass through to our customers. We use these financial measures because we believe the amounts as adjusted better represent the coal sales prices we achieved within our operating segments. Since other companies may calculate coal sales prices per ton differently, our calculation may not be comparable to similarly titled measures used by those companies. For the year ended December 31, 2010, transportation costs per ton were $0.08 for the Powder River Basin and $3.34 for the Western Bituminous. For the year ended December 31, 2009, transportation costs per ton were $0.12 for the Powder River Basin and $3.18 for the Western Bituminous region.

(2)		Operating margin per ton is calculated as coal sales revenues less cost of coal sales and depreciation, depletion and amortization, including amortization of acquired sales contracts, divided by tons sold.

Powder River Basin — The increase in sales volumes in the Powder River Basin in 2010 when compared with 2009 resulted primarily from the acquisition of the Jacobs Ranch mining operations on October 1, 2009, although improving demand for Powder River Basin coal in the second half of 2010 also had a positive impact on sales volumes. Sales prices during 2010 were slightly lower when compared with 2009, primarily reflecting the roll-off of contracts committed when market conditions were more favorable. On a per-ton basis, operating margins in 2010 increased, as a decrease in per-ton costs offset the effect of lower average sales price. The decrease in per-ton costs resulted from efficiencies achieved from combining the acquired Jacobs Ranch mining operations with our existing Black Thunder operations, as well as a decrease in hedged diesel fuel costs.

Western Bituminous — In the Western Bituminous region, despite a soft steam coal market in the region and the two outages at the Dugout Canyon mine in 2010, sales volumes decreased only slightly compared to 2009. Sales volumes in 2009 were also affected by weaker market conditions that had an impact on our ability to market coal with a high ash content, which resulted from geologic conditions at our West Elk mine, and the decision to reduce production accordingly. A preparation plant at the West Elk mine was placed into service in the fourth quarter of 2010 to address any future quality issues arising from sandstone intrusions similar to those we encountered previously. Despite the detrimental impact in 2009 on our per-ton realizations of selling coal with a higher ash content, our realizations increased only slightly in 2010, due to the soft steam coal market and an unfavorable mix of customer contracts. Effective cost control in the region resulted in the higher per-ton operating margins in 2010, partially offset by the impact of the two outages at the Dugout Canyon mine in 2010.

Net interest expense. The following table summarizes our net interest expense for the year ended December 31, 2010 and compares it with the information for the year ended December 31, 2009:


	Year Ended December 31						Increase in Net Income
	2010			2009			$		%
	(Dollars in thousands)
Interest expense	$	(61,614	)	$	(67,605	)		5,991		8.9	%
Interest income, primarily from Arch Coal		52,444			46,571			5,873		12.6

Total	$	(9,170	)	$	(21,034	)	$	11,864		56.4	%

Interest expense consists primarily of interest on our 6.75% senior notes, the discount on trade accounts receivable sold to Arch Coal under Arch Coal’s accounts receivable securitization program, interest on our commercial paper, and interest on a loan from Arch Coal. On September 8, 2010, we redeemed $500.0 million aggregate principal amount of the outstanding 6.75% senior notes at a redemption price of 101.125%. We funded this redemption with cash transferred from Arch Coal in the form of a loan of $225.0 million and a repayment of a portion of the balance receivable from Arch Coal. See further discussion under the heading “Liquidity and Capital Resources”. The decrease in net interest expense in 2010 compared to 2009 is primarily due to the net decrease in our total debt balances as a result of the redemption.

Our cash transactions are managed by Arch Coal. Cash paid to or from us that is not considered a distribution, a contribution, or a loan is recorded through a note receivable from Arch Coal. The balance earns at the prime interest rate. The increase in interest income during 2010 when compared to 2009 resulted primarily from higher average receivable balance during the majority of 2010.

Other non-operating expense. The following table summarizes our other non-operating expense for the year ended December 31, 2010 and compares it with the information for the year ended December 31, 2009:


						Decrease
	Year Ended December 31					in Net Income
	2010			2009		$			%
	(Dollars in thousands)
Loss on early extinguishment of debt	$	(6,776	)	$	—		(6,776	)		(100	)%

Amounts reported as non-operating consist of income or expense resulting from our financing activities, other than interest costs. The loss on early extinguishment of debt relates to the redemption of $500 million in principal amount of the 6.75% senior notes. The loss includes the payment of $5.6 million of redemption premium and the write-off of $3.2 million of unamortized debt financing costs, partially offset by the write-off of $2.1 million of the original issue premium.

Year Ended December 31, 2009 Compared to Year Ended December 31, 2008

Summary. Our results for the year ended December 31, 2009 when compared to the year ended December 31, 2008 were influenced primarily by lower sales volumes due to weak coal markets.

Revenues. The following table summarizes information about coal sales during the year ended December 31, 2009 and compares it with the information for the year ended December 31, 2008:


	Year Ended December 31				Increase (Decrease)
	2009		2008		Amount			%
	(Amounts in thousands, except per ton data and percentages)
Coal sales	$	1,651,389	$	1,758,008	$	(106,619	)		(6.1	)%
Tons sold		107,649		120,361		(12,712	)		(10.6	)%
Coal sales realization per ton sold	$	15.34	$	14.61	$	0.73			5.0	%

Coal sales decreased in 2009 from 2008 primarily due lower sales volumes, resulting from weak coal markets, partially offset by the effect of higher price realizations in both segments. We have provided more information about the tons sold and the coal sales realizations per ton by operating segment under the heading “Operating segment results.”

Costs, expenses and other. The following table summarizes costs, expenses and other components of operating income for the year ended December 31, 2009 and compares it with the information for the year ended December 31, 2008:


							Increase (Decrease)
	Year Ended December 31						in Net Income
	2009			2008			$			%
	(Dollars in thousands)
Cost of coal sales	$	1,398,663		$	1,395,176		$	(3,487	)		(0.2	)%
Depreciation, depletion and amortization		159,755			155,400			(4,355	)		(2.8	)
Amortization of acquired sales contracts, net		19,623			(705	)		(20,328	)		N/A
Selling, general and administrative expenses		44,513			31,940			(12,573	)		(39.4	)
Other operating income, net		(10,475	)		(4,195	)		6,280			149.7

Total	$	1,612,079		$	1,577,616		$	(34,463	)		(2.2	)%

Cost of coal sales. Our cost of coal sales decreased in 2009 from 2008 due to a decrease of $25.3 million in transportation costs due to a decrease in barge and export sales, mostly offset by the impact of higher per-ton costs resulting from lower production levels. We have provided more information about our operating segments under the heading “Operating segment results.”

Depreciation, depletion and amortization. When compared with 2008, higher depreciation and amortization costs in 2009 resulted from the acquisition of the Jacobs Ranch mining complex on October 1, 2009 and the amortization of development costs related to the seam at the West Elk mine where we commenced longwall production in the fourth quarter of 2008, partially offset by the impact of lower volume levels on depletion and amortization costs calculated on a units-of-production method. We have provided more information about our operating segments under the heading “Operating segment results” and our capital spending in the section entitled “Liquidity and Capital Resources.”

Amortization of acquired sales contracts, net. The increase in the amortization of acquired sales contracts, net relates to the acquisition of the Jacobs Ranch mining operation. The sales contracts acquired by Arch Coal were not contributed to us, however, the amortization of these acquired sales contracts is reflected in our results. The fair values of acquired sales contracts are amortized over the tons of coal shipped during the term of the contracts.

Other operating income, net. The net increase is primarily the result of an increase in income from contract settlements.

Operating segment results. The following table shows results by operating segment for the year ended December 31, 2009 and compares it with the information for the year ended December 31, 2008:


	Year Ended December 31				Increase (Decrease)
	2009		2008		Amount			%
	(Amounts in thousands, except
	per ton data and percentages)
Powder River Basin
Tons sold		90,956		99,952		(8,996	)		(9.0	)%
Coal sales realization per ton sold(1)	$	12.11	$	11.02	$	1.09			9.9	%
Operating margin per ton sold(2)	$	0.47	$	0.85	$	(0.38	)		(44.7	)%
Western Bituminous
Tons sold		16,693		20,409		(3,716	)		(18.2	)%
Coal sales realization per ton sold(1)	$	29.11	$	27.46	$	1.65			6.0	%
Operating margin per ton sold(2)	$	1.66	$	5.84	$	(4.18	)		(71.6	)%


(1)		Coal sales prices per ton exclude certain transportation costs that we pass through to our customers. We use these financial measures because we believe the amounts as adjusted better represent the coal sales prices we achieved within our operating segments. Since other companies may calculate coal sales prices per ton differently, our calculation may not be comparable to similarly titled measures used by those companies. For the year ended December 31, 2009, transportation costs per ton were $0.12 for the Powder River Basin and $3.18 for the Western Bituminous. For the year ended December 31, 2008, transportation costs per ton were $0.03 for the Powder River Basin and $4.57 for the Western Bituminous region.

(2)		Operating margin per ton is calculated as coal sales revenues less cost of coal sales and depreciation, depletion and amortization, including amortization of acquired sales contracts, divided by tons sold.

Powder River Basin — The decrease in sales volume in the Powder River Basin in 2009 when compared with 2008 is due to a decline in demand stemming from weak market conditions. At the Black Thunder mining complex, in response to these conditions, we reduced production and idled one dragline in the fourth quarter of 2008 and another dragline in May 2009, along with the related support equipment. This reduction was partially offset by the impact of the contribution of the Jacobs Ranch mining complex assets on October 1, 2009. Increases in sales prices during 2009, when compared with 2008, primarily reflect higher pricing from contracts committed during 2008, when market conditions were more favorable, partially offset by the effect of lower pricing on market-index

priced tons and the effect of lower sulfur dioxide allowance pricing. On a per-ton basis, operating margins in 2009 decreased compared to 2008 due to an increase in per-ton costs. The increase in annual per-ton costs, despite our cost containment efforts, resulted primarily from the effect of spreading fixed costs over lower volume levels; however, our per-ton operating costs improved in the fourth quarter of 2009, as a result of synergies achieved from the combined mining operations.

Western Bituminous — In the Western Bituminous region, we sold fewer tons in 2009 than in 2008 due to weak market conditions as well as quality issues at the West Elk mining complex. In the first half of 2009, we encountered sandstone intrusions at the West Elk mining complex that resulted in a higher ash content in the coal produced, and declining coal demand had an impact on our efforts to market this coal. As a result of the weak market demand for this coal, we reduced our production levels at the mine. The detrimental impact on our per-ton realizations of selling coal with a higher ash content offset the beneficial impact of the roll-off of lower-priced legacy contracts in 2008. Lower per-ton operating margins during 2009 were the result of the West Elk quality issues and the lower production levels, however, per-ton costs decreased in the fourth quarter as the longwall advanced into more favorable geology, as expected, improving our margins.

Net interest expense. The following table summarizes our net interest expense for the year ended December 31, 2009 and compares it with the information for the year ended December 31, 2008:


							Decrease
	Year Ended December 31						in Net Income
	2009			2008			$		%
				(Dollars in thousands)
Interest expense	$	(67,605	)	$	(66,556	)		1,049		1.6	%
Interest income, primarily from Arch Coal		46,571			74,869			28,298		37.8

Total	$	(21,034	)	$	8,313		$	29,347		353.0	%

Interest expense consists of interest on our 6.75% senior notes, the discount on trade accounts receivable sold to Arch Coal under Arch Coal’s accounts receivable securitization program and interest on our commercial paper. The increase in interest expense in 2009 when compared with 2008 resulted from a decrease in the amount of interest costs capitalized from $11.7 million in 2008 to $0.8 million in 2009. Partially offsetting the decrease in capitalized interest costs was a decrease in the discount on accounts receivable sold to Arch Coal, due to lower interest rates and a decrease in total receivables sold in 2009 compared to 2008.

Our cash transactions are managed by Arch Coal. Cash paid to or from us that is not considered a distribution or a contribution is recorded through a receivable from Arch Coal. The receivable balance earns interest from Arch Coal at the prime interest rate. The decrease in interest income results primarily from a lower prime interest rate during 2009 as compared to 2008.

Liquidity and Capital Resources

Liquidity and capital resources

Our primary sources of cash are coal sales to customers, our commercial paper program and debt related to significant transactions. Excluding any significant business acquisitions, we generally satisfy our working capital requirements and fund capital expenditures and debt-service obligations with cash generated from operations, and if necessary, from Arch Coal. Arch Coal manages our cash transactions. Cash paid to or from us that is not considered a distribution or a contribution is recorded through a note receivable from Arch Coal, with exception of the borrowings under the intercompany credit agreement discussed below. The receivable balance earns interest at the prime interest rate. We are also party to Arch Coal’s accounts receivable securitization program. Under the program, we sell our receivables to a subsidiary of Arch Coal without recourse at a discount based on the prime rate and days sales outstanding.

We believe that cash generated from operations will be sufficient to meet working capital requirements, anticipated capital expenditures and scheduled debt payments for at least the next several years. We manage our exposure to changing commodity prices for our long-term coal contract portfolio through the use of long-term coal supply agreements. We enter into fixed price, fixed volume supply contracts with terms generally greater than one year with customers with whom we have historically had limited collection issues. Our ability to satisfy debt service obligations, to fund planned capital expenditures and to make acquisitions will depend upon our future operating performance, which will be affected by prevailing economic conditions in the coal industry and financial, business and other factors, some of which are beyond our control.

On September 8, 2010 we redeemed $500.0 million aggregate principal amount of our subsidiary Arch Western Finance LLC’s outstanding 6.75% senior notes due in 2013 at a redemption price of 101.125%. We funded this redemption with cash transferred from Arch Coal in the form of a loan of $225.0 million and a repayment of a portion of the balance receivable from Arch Coal.

Arch Coal made the loan pursuant to an intercompany credit agreement. Under the intercompany credit agreement, we may borrow up to $675.0 million through July 1, 2013, or such later date as designated by Arch Coal. Interest on loans outstanding under the agreement is calculated at a per annum rate equal to the three month LIBOR rate plus 200 or 250 basis points, depending on a leverage ratio, as defined in the agreement, at the date the rate is determined. Interest is due on any outstanding loans on the first day of each calendar quarter. We may repay the balance of the loan, in whole or in part, at any time, without penalty.

Under Arch Coal’s accounts receivable securitization program, we sold $1.7 billion of trade accounts receivable to Arch Coal during 2010, at a total discount of $4.0 million. During 2009, we sold $1.4 billion of trade accounts receivable to Arch Coal, at a total discount of $3.5 million. During 2008, we sold $1.7 billion of trade accounts receivable to Arch Coal, at a total discount of $7.1 million.

Our commercial paper placement program provides us with short-term financing. Under the program, as amended, we may sell interest-bearing or discounted short-term unsecured debt obligations with maturities of no more than 270 days. The commercial paper placement program is supported by a line of credit that is subject to renewal annually and expires April 30, 2011. On March 25, 2010, we entered into an amendment to our commercial paper program which decreased the maximum aggregate principal amount of the program to $75 million from $100 million, as the credit markets have affected our ability to issue commercial paper. We had commercial paper outstanding of $56.9 million at December 31, 2010 and $49.5 million at December 31, 2009.

Our subsidiary, Arch Western Finance LLC, has outstanding an aggregate principal amount of $450.0 million of 6.75% senior notes due on July 1, 2013, subsequent to the redemption discussed previously. Interest is payable on the notes on January 1 and July 1 of each year. The senior notes are secured by an intercompany note from Arch Coal to Arch Western. The indenture under which the senior notes were issued contains certain restrictive covenants that limit Arch Western’s ability to, among other things, incur additional debt, sell or transfer assets and make certain investments. The redemption price of the notes, reflected as a percentage of the principal amount, is: 101.125% for notes redeemed prior to July 1, 2011 and 100% for notes redeemed on or after July 1, 2011.

The following is a summary of cash provided by or used in each of the indicated types of activities during the past three years:


	Year Ended December 31
	2010			2009			2008
	(Dollars in thousands)
Cash provided by (used in):
Operating activities	$	438,376		$	178,119		$	396,582
Investing activities		(92,704	)		(157,729	)		(384,458	)
Financing activities		(272,674	)		(16,422	)		(9,521	)

Cash provided by operating activities increased $260.3 million in 2010 compared to 2009, primarily as a result of an increase in our profitability in 2010 when compared with 2009, driven largely by higher sales volumes as discussed in “Results of Operations”, as well as a benefit in 2010 from the timing of payments on accounts and production taxes payable. Cash provided by operating activities decreased in 2009 compared to 2008, primarily as a result of a decrease in our profitability in 2009 when compared with 2008, due to weaker coal markets.

Cash used in investing activities was $65.0 million less in 2010 compared to the amount used in 2009, primarily due to a $22.8 million reduction in capital expenditures and net cash received from Arch Coal of $12.8 million in 2010, compared with net cash loaned to Arch Coal of $32.8 million in 2009. The amounts repaid in 2010 were primarily related to the redemption of the 6.75% notes discussed previously.

Cash used in investing activities in 2009 was $226.7 million less than was used in 2008, primarily due to a $161.2 million reduction in capital expenditures and a $67.6 million decrease in cash used related to our net receivable position with Arch Coal. During 2009, we spent approximately $19.0 million on additional longwall equipment at the West Elk mining complex in Colorado and approximately $38.0 million on a new shovel and haul trucks at the Black Thunder mine in Wyoming. During 2008, we spent approximately $86.5 million on the construction of the loadout facility at our Black Thunder mine in Wyoming and approximately $132.1 million for the transition to the new reserve area at our West Elk mining complex. We completed the work on the loadout facility and transitioned to the new seam at West Elk in the fourth quarter of 2008.

Cash used in financing activities was $256.3 million more during 2010 than in 2009. As previously discussed, Arch Coal made a loan to us in the amount of $225.0 million, which proceeds, along with the repayment of the intercompany note mentioned above, were used to fund the redemption on September 8, 2010 of $500.0 million aggregate principal amount of our outstanding 6.75% senior notes due in 2013 at a redemption price of 101.125%. Cash used in financing activities was $6.9 million more during 2009 compared to 2008, due to an increase in net payments under our commercial paper program. In 2008, we increased the maximum aggregate principal amount under the commercial paper program from $75.0 million to $100.0 million, but as discussed previously, the credit markets had affected our ability to issue commercial paper up to the maximum amount allowed under the program at that time.

Contractual Obligations

The following is a summary of our significant contractual obligations as of December 31, 2010:


	Payments Due by Period
	2011		2012-2013		2014-2015		After 2015		Total
	(Dollars in thousands)
Long-term debt, including related interest	$	87,383	$	495,563	$	—	$	—	$	582,946
Note payable to Arch Coal, including related interest		6,278		234,417		—		—		240,695
Operating leases		26,351		43,891		30,523		13,265		114,030
Coal lease rights		7,272		7,286		1,907		5,881		22,346
Unconditional purchase obligations		88,289		16,337		17,332		48,089		170,047

Total contractual obligations	$	215,573	$	797,494	$	49,762	$	67,235	$	1,130,064

The related interest on long-term debt and the note payable to Arch Coal was calculated using rates in effect at December 31, 2010 for the remaining term of outstanding borrowings.

Coal lease rights represent non-cancelable royalty lease agreements, as well as lease bonus payments due.

Unconditional purchase obligations include open purchase orders and other purchase commitments, which have not been recognized as a liability. The commitments in the table above relate to contractual commitments for the purchase of materials and supplies, payments for services and capital expenditures.

The table above excludes our asset retirement obligations. Our consolidated balance sheet reflects a liability of $308.4 million for asset retirement obligations that arise from SMCRA and similar state statutes, which require that mine property be restored in accordance with specified standards and an approved reclamation plan. Asset retirement obligations are recorded at fair value when incurred and accretion expense is recognized through the expected date of settlement. Determining the fair value of asset retirement obligations involves a number of estimates, as discussed in the section entitled “Critical Accounting Policies”, including the timing of payments to satisfy the obligations. The timing of payments to satisfy asset retirement obligations is based on numerous factors, including mine closure dates. You should see the notes to our consolidated financial statements for more information about our asset retirement obligations.

The table above also excludes certain other obligations reflected in our consolidated balance sheet, including our allocation of obligations under Arch Coal’s pension and postretirement benefit plans and obligations under our self-insured workers’ compensation program. We are not obligated to make contributions directly to Arch Coal’s pension and postretirement plans, but we are charged through the intercompany receivable for an allocated portion of Arch Coal’s contributions. The timing of Arch Coal’s contributions to their pension plans varies based on a number of factors, including changes in the fair value of plan assets and actuarial assumptions. You should see the section entitled “Critical Accounting Policies” for more information about these assumptions. You should see the notes to our consolidated financial statements for more information about the amounts we have recorded for the pension and postretirement benefit obligations.

Off-Balance Sheet Arrangements

In the normal course of business, we are a party to certain off-balance sheet arrangements. These arrangements include guarantees, indemnifications, financial instruments with off-balance sheet risk, such as bank letters of credit and performance or surety bonds. Liabilities related to these arrangements are not reflected in our consolidated balance sheets, and we do not expect any material adverse effects on our financial condition, results of operations or cash flows to result from these off-balance sheet arrangements.

We use a combination of surety bonds, corporate guarantees (e.g., self bonds) and letters of credit to secure our financial obligations for reclamation, workers’ compensation, coal lease obligations and other obligations as follows as of December 31, 2010:


	Reclamation		Lease
	Obligations		Obligations		Other		Total
	(Dollars in thousands)
Self bonding	$	403,403	$	—	$	—	$	403,403
Surety bonds		33,197		19,211		2,278		54,686

Critical Accounting Policies

We prepare our financial statements in accordance with accounting principles that are generally accepted in the United States. The preparation of these financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses as well as the disclosure of contingent assets and liabilities. Management bases our estimates and judgments on historical experience and other factors that are believed to be reasonable under the circumstances. Additionally, these estimates and judgments are discussed with Arch Coal’s audit committee on a periodic basis. Actual results may differ from the estimates used under different assumptions or conditions. We have provided a description of all significant accounting policies in the notes to our consolidated financial statements. We believe that of these significant accounting policies, the following may involve a higher degree of judgment or complexity:

Asset Retirement Obligations

Our asset retirement obligations arise from SMCRA and similar state statutes, which require that mine property be restored in accordance with specified standards and an approved reclamation plan. Significant reclamation activities include reclaiming refuse and slurry ponds, reclaiming the pit and support acreage at surface mines, and sealing portals at deep mines. Our asset retirement obligations are initially recorded at fair value, or the amount at which the obligations could be settled in a current transaction between willing parties. This involves determining the present value of estimated future cash flows on a mine-by-mine basis based upon current permit requirements and various estimates and assumptions, including estimates of disturbed acreage, reclamation costs and assumptions regarding productivity. We estimate disturbed acreage based on approved mining plans and related engineering data. Since we plan to use internal resources to perform the majority of our reclamation activities, our estimate of reclamation costs involves estimating third-party profit margins, which we base on our historical experience with contractors that perform certain types of reclamation activities. We base productivity assumptions on historical experience with the equipment that we expect to utilize in the reclamation activities. In order to determine fair value, we discount our estimates of cash flows to their present value. We base our discount rate on the rates of treasury bonds with maturities similar to expected mine lives, adjusted for our credit standing. In 2009, we added $75.1 million to our liability for asset retirement obligations as a result of the acquisition of the Jacobs Ranch mining complex.

Accretion expense is recognized on the obligation through the expected settlement date. Accretion expense was $24.0 million in 2010 and $21.0 million in 2009. On at least an annual basis, we review our entire reclamation liability and make necessary adjustments for permit changes as granted by state authorities, changes in the timing of reclamation activities, and revisions to cost estimates and productivity assumptions, to reflect current experience. Adjustments to the liability resulting from changes in estimates were an increase in the liability of $8.8 million in 2010 and a decrease in the liability of $45.3 million in 2009. The 2009 reduction in the liability resulted from changes to the Black Thunder mine’s pit configuration upon the integration the Jacobs Ranch mining operations. Any difference between the recorded amount of the liability and the actual cost of reclamation will be recognized as a gain or loss when the obligation is settled. We expect our actual cost to reclaim our properties will be less than the expected cash flows used to determine the asset retirement obligation. At December 31, 2010, our balance sheet reflected asset retirement obligation liabilities of $308.4 million, including amounts classified as a current liability. As of December 31, 2010, we estimate the aggregate undiscounted cost of final mine closures to be approximately $616.1 million.

Employee Benefit Plans

We participate in Arch Coal’s non-contributory defined benefit pension plans covering essentially all of our salaried and hourly employees. Benefits are generally based on the employee’s age and compensation. Arch Coal allocates the net periodic benefit cost and benefit obligation to us based on participant information. The calculation of our net periodic benefit costs (expense) and benefit obligation (liability) associated with Arch Coal’s defined benefit pension plans requires the use of a number of assumptions that we deem to be “critical accounting estimates.” Changes in these assumptions can result in different pension expense and liability amounts, and actual experience can differ from the assumptions. These assumptions include the long term rate of return on plan assets and the

discount rate, representing the interest rate at which pension benefits could be effectively settled. Arch Coal reports separately on the assumptions used in the determination of net periodic benefit costs and benefit obligation associated with its defined benefit plans.

We also currently provide certain postretirement medical and life insurance coverage for eligible employees under Arch Coal’s plans. Generally, covered employees who terminate employment after meeting eligibility requirements are eligible for postretirement coverage for themselves and their dependents. The salaried employee postretirement benefit plans are contributory, with retiree contributions adjusted periodically, and contain other cost-sharing features such as deductibles and coinsurance. Arch Coal allocates the net postretirement benefit cost and benefit obligation based on participant information. The calculation of our net postretirement benefit costs (expense) and benefit obligation (liability) associated with Arch Coal’s postretirement benefit plans requires the use of assumptions that we deem to be “critical accounting estimates,” primarily the discount rate. Arch Coal reports separately on the assumptions used in the determination of net periodic benefit costs and benefit obligation associated with its postretirement plans.

Actuarial assumptions are required to determine the amounts reported by us related to Arch Coal’s defined benefit pension plan and the postretirement benefit plan. The impact of lowering the expected long-term rate of return on pension plan assets 0.5% in 2010 would have been an increase in our expense of approximately $0.6 million. The impact of lowering the discount rate 0.5% in 2010 would have been an increase in our net periodic pension and postretirement costs of approximately $1.8 million.

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

We manage our commodity price risk for our long-term coal contract portfolio through the use of long-term coal supply agreements, rather than through the use of derivative instruments. The majority of our tonnage is sold under long-term contracts. We are also exposed to price risk related to the value of sulfur dioxide emission allowances that are a component of quality adjustment provisions in many of our coal supply contracts. We manage this risk through the use of long-term coal supply agreements.

We are also exposed to the risk of fluctuations in cash flows related to our purchase of diesel fuel. We use approximately 45 to 50 million gallons of diesel fuel annually in our operations. Arch Coal enters into heating oil swaps and options to reduce volatility in the price of diesel fuel for our operations. The swap agreements essentially fix the price paid for diesel fuel by requiring us to pay a fixed heating oil price and receive a floating heating oil price. The call options protect against increases in diesel fuel by granting us the right to participate in increases in heating oil prices. The cash settlements related to these swaps and options are allocated to us through the Arch Coal intercompany account.

We are exposed to market risk associated with fluctuating interest rates on our outstanding commercial paper and the note payable to Arch Coal. A one percentage point increase in the interest rates related to these borrowings would result in an annualized increase in interest expense of $2.8 million, based on borrowing levels at December 31, 2010.

ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA.

The consolidated financial statements and consolidated financial statement schedule of Arch Western Resources, LLC, and subsidiaries are included in this Annual Report on Form 10-K beginning on page F-1.

ITEM 9. CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND FINANCIAL DISCLOSURE.

None.

ITEM 9A. CONTROLS AND PROCEDURES.

We performed an evaluation under the supervision and with the participation of our management, including our chief executive officer and chief financial officer, of the effectiveness of the design and operation of our disclosure controls and procedures as of December 31, 2010. Based on that evaluation, our management, including our chief executive officer and chief financial officer, concluded that the disclosure controls and procedures were effective as of such date. There were no changes in internal control over financial reporting that occurred during our fiscal quarter ended December 31, 2010 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

We incorporate by reference the report of independent registered public accounting firm and management’s report on internal control over financial reporting included on pages F-2 and F-3, respectively, of this Annual Report on Form 10-K.

ITEM 9B. OTHER INFORMATION.

None.

PART III

ITEM 10. DIRECTORS, EXECUTIVE OFFICERS AND CORPORATE GOVERNANCE

Our managing member is an indirect, wholly-owned subsidiary of Arch Coal, Inc. As a result, we are effectively managed by the management of Arch Coal. You should see the list of Arch Coal’s executive officers and related information under “Executive Officers” beginning on page 20.

The following is a list of directors of Arch Coal, other than Messrs. Eaves and Leer, whose biographical information is contained under “Executive Officers” beginning on page 20, their ages on February 28, 2011 and biographical information:


			Director of
			Arch Coal
Name	Age		Since		Occupation and Other Information
James R. Boyd		64		1990	Mr. Boyd served as chairman of the board of directors from 1998 to April 2006, when he was appointed lead director of Arch Coal. Mr. Boyd served as Senior Vice President and Group Operating Officer of Ashland Inc. from 1989 until his retirement in 2002. Mr. Boyd also serves on the board of directors of Halliburton Inc.

Governor David Freudenthal		60		2011	Governor Freudenthal served as the Governor of Wyoming from 2003 until January 2011. Prior to his service as governor, he served as U.S. Attorney for the District of Wyoming. Governor Freudenthal current serves as an Adjunct Professor at the University of Wyoming.

Patricia F. Godley		62		2004	Since 1998, Ms. Godley has been a partner with the law firm of Van Ness Feldman, practicing in the areas of economic and environmental regulation of electric utilities and natural gas companies. Ms. Godley is also a director of the United States Energy Association.

Douglas H. Hunt		58		1995	Since 1995, Mr. Hunt has served as Director of Acquisitions of Petro-Hunt, LLC, a private oil and gas exploration and production company.

Brian J. Jennings		50		2006	Since February 2009, Mr. Jennings has been President and Chief Executive Officer of Rise Energy Partners, L.P. From February 2007 to June 2008, Mr. Jennings served as Chief Financial Officer of Energy Transfer Partners GP, L.P., the general partner of Energy Transfer Partners, L.P., a publicly-traded partnership owning and operating intrastate and interstate natural gas pipelines. From 2004 to December 2006, Mr. Jennings served as Senior Vice President-Corporate Finance and Development and Chief Financial Officer of Devon Energy Corporation.

J. Thomas Jones		61		2010	Mr. Jones has been Chief Executive Officer of West Virginia United Health System located in Fairmont, West Virginia since 2002. From 2000 to 2002, Mr. Jones served as Chief Executive Officer of Genesis Hospital System in Huntington, West Virginia. Mr. Jones is also a director of Premier, Inc. and Health Partners Network.


			Director of
			Arch Coal
Name	Age		Since		Occupation and Other Information
Thomas A. Lockhart		75		2003	Mr. Lockhart has been a member of the Wyoming State House of Representatives since 2000. Mr. Lockhart also serves on the board of directors of Blue Cross Blue Shield of Wyoming.

A. Michael Perry		74		1998	Mr. Perry served as Chairman of Bank One, West Virginia, N.A. from 1993 and as its Chief Executive Officer from 1983 until his retirement in 2001. Mr. Perry also serves on the board of directors of Champion Industries, Inc. and Portec Rail Products, Inc.

Robert G. Potter		71		2001	Mr. Potter was Chairman and Chief Executive Officer of Solutia, Inc. from 1997 until his retirement in 1999. He is also an investor in several private companies and has served as a member of the board of directors for six other companies.

Theodore D. Sands		65		1999	Since 1999, Mr. Sands has served as President of HAAS Capital, LLC, a private consulting and investment company. Mr. Sands served as Managing Director, Investment Banking for the Global Metals/Mining Group of Merrill Lynch & Co. from 1982 until February 1999. Mr. Sands has also served as a member of the board of directors for several other companies.

Wesley M. Taylor		68		2005	Mr. Taylor was President of TXU Generation, a company engaged in electricity infrastructure ownership and management. Mr. Taylor served at TXU for 38 years prior to his retirement in 2004. Mr. Taylor also serves on the board of directors of FirstEnergy Corporation.

Peter I. Wold		63		2010	Mr. Wold is President and co-owner of Wold Oil Properties, Inc., an oil and gas exploration and production company. He is also Vice President of American Talc Company, a corporation that mines and processes talc in Western Texas. He presently chairs the Wyoming Enhanced Oil Recovery Commission and is a director of the Oppenheimer Funds, Inc., New York Board. Mr. Wold has also served in the Wyoming House of Representatives and as a director of the Denver Branch of the Kansas City Federal Reserve Bank.

All of our officers and employees must act ethically at all times and in accordance with the Arch Coal code of conduct, which is published under “Corporate Governance” in the Investors section of Arch Coal’s website at archcoal.com and available in print upon request. Amendments to or waivers from (to the extent applicable to an executive officer of the company) the code will be posted on Arch Coal’s website. Reference is made to Item 10. Directors, Executive Officers and Corporate Governance of Arch Coal’s Annual Report on Form 10-K for its fiscal year ended December 31, 2010, which is incorporated by reference in this Item 10.

ITEM 11. EXECUTIVE COMPENSATION.

Our managing member is an indirect wholly-owned subsidiary of Arch Coal. As a result, we are effectively managed by the management of Arch Coal. Arch Coal reports separately on the executive compensation of its management. Reference is made to Item 11. Executive Compensation of Arch Coal’s Annual Report on Form 10-K for its fiscal year ended December 31, 2010, which is incorporated by reference in this Item 11.

ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT AND RELATED STOCKHOLDER MATTERS

Arch Coal owns 99.5% of our common membership interests. In addition to the remaining 0.5% of our common membership interests, BP p.l.c. owns a preferred membership interest. The stockholders of Arch Coal may be deemed to beneficially own an interest in our membership interests by virtue of their ownership of shares of common stock of Arch Coal. Arch Coal reports separately on the ownership by its directors, executive officers and significant stockholders of shares of its common stock. Reference is made to Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder

Matters of Arch Coal’s Annual Report on Form 10-K for its fiscal year ended December 31, 2010, which is incorporated by reference in this Item 12.

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS, AND DIRECTOR INDEPENDENCE.

We are subject to the conflict of interest restrictions contained in Arch Coal’s code of conduct and do not have a separate policy governing transactions with related persons. As a result, transactions with Arch Coal may not be at arms length. If the transactions were negotiated with an unrelated party, the impact could be material to our results of operations.

Our cash transactions are managed by Arch Coal. Cash paid to or from us that is not considered a distribution or a contribution is recorded in an Arch Coal receivable account. In addition, any amounts owed between us and Arch Coal are recorded in the account. The receivable from Arch Coal was $1.5 billion at December 31, 2010 and $1.5 billion at December 31, 2009. This amount earns interest from Arch Coal at the prime interest rate. Interest earned was $52.2 million in 2010, $46.5 million in 2009 and $74.6 million in 2008. The receivable is payable on demand; however, it is currently management’s intention to not demand payment of the receivable within the next year. Therefore, the receivable is classified on our balance sheets as noncurrent.

On September 8, 2010, we received a loan of $225.0 million and a repayment of a portion of the balance receivable from Arch Coal to redeem $500.0 million aggregate principal amount of the outstanding 6.75% senior notes at a redemption price of 101.125%. Interest incurred on the loan was $1.9 million for the year ended December 31, 2010.

On February 10, 2006, Arch Coal established an accounts receivable securitization program. Under the program, we sell our receivables to Arch Coal without recourse at a discount based on the prime rate and days sales outstanding. During 2010, we sold $1.7 billion of trade accounts receivable to Arch Coal, at a discount of $4.0 million. During 2009, we sold $1.4 billion of trade accounts receivable to Arch Coal, at a discount of $3.5 million.

We mine on tracts that are owned or leased by Arch Coal and subleased to us. Royalties on all properties leased from Arch Coal are 7% of the value of the coal mined and removed from the leased land, pursuant to Federal coal regulations. No advance royalties are required under these sublease agreements. We incurred production royalties of $92.4 million in 2010, $47.8 million in 2009 and $35.8 million in 2008 to Arch Coal under sublease agreements.

Amounts charged to the intercompany account for our allocated portion of pension and postretirement contributions totaled $10.9 million in 2010, $11.1 million in 2009 and $1.1 million in 2008.

We are charged selling, general and administrative services fees by Arch Coal. Expenses are allocated based on Arch Coal’s best estimates of proportional or incremental costs, whichever is more representative of costs incurred by Arch Coal on our behalf. Amounts allocated to us by Arch Coal were $36.0 million in 2010, $44.5 million in 2009 and $31.9 million in 2008. Such amounts are reported as selling, general and administrative expenses in our statements of income.

Our managing member is an indirect, wholly-owned subsidiary of Arch Coal. As a result, we are effectively managed by the management of Arch Coal. Arch Coal reports separately on the independence of its directors. Reference is made to Item 13. Certain Relationships and Related Transactions, and Director Independence of Arch Coal’s Annual Report on Form 10-K for its fiscal year ended December 31, 2010, which is incorporated by reference in this Item 13.

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES.

Ernst & Young LLP is our independent registered public accounting firm. Our audit fees are determined as part of the overall audit fees for Arch Coal and are approved by the audit committee of the board of directors of Arch Coal. Arch Coal reports separately on the fees and services of its principal accountants. Reference is made to Item 14. Principal Accounting Fees and Services of Arch Coal’s Annual Report on Form 10-K for its fiscal year ended December 31, 2010, which is incorporated by reference in this Item 14.

PART IV

ITEM 15. EXHIBITS AND FINANCIAL STATEMENT SCHEDULES.

The consolidated financial statements and consolidated financial statement schedule of Arch Western Resources, LLC and subsidiaries are included in this Annual Report on Form 10-K beginning on page F-1.

You should see the exhibit index for a list of exhibits included in this Annual Report on Form 10-K.

FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

The consolidated financial statements of Arch Western Resources, LLC and subsidiaries and reports of its independent registered public accounting firm and management follow.

Index to Consolidated Financial Statements


Report of Independent Registered Public Accounting Firm			F-2
Management’s Report on Internal Control over Financial Reporting			F-3
Consolidated Statements of Income for the Years Ended December 31, 2010, 2009 and 2008			F-4
Consolidated Balance Sheets at December 31, 2010 and 2009			F-5
Consolidated Statements of Cash Flows for the Years Ended December 31, 2010, 2009 and 2008			F-6
Consolidated Statements of Non-Redeemable Membership Interest for the Years Ended December 31, 2010, 2009 and 2008			F-7
Notes to Consolidated Financial Statements			F-8
Financial Statement Schedule			F-26

F-1

Report of Independent Registered Public Accounting Firm

The Members
Arch Western Resources, LLC

We have audited the accompanying consolidated balance sheets of Arch Western Resources, LLC and subsidiaries (the Company) as of December 31, 2010 and 2009, and the related consolidated statements of income, non-redeemable membership interest, and cash flows for each of the three years in the period ended December 31, 2010. Our audits also included the financial statement schedule listed in the index at Item 15. These financial statements and schedule are the responsibility of the Company’s management. Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. We were not engaged to perform an audit of the Company’s internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the consolidated financial position of Arch Western Resources, LLC and subsidiaries at December 31, 2010 and 2009, and the consolidated results of its operations and its cash flows for each of the three years in the period ended December 31, 2010, in conformity with U.S. generally accepted accounting principles. Also, in our opinion, the related financial statement schedule, when considered in relation to the basic financial statements taken as a whole, presents fairly in all material respects the information set forth therein.

/s/ Ernst & Young LLP

St. Louis, Missouri
March 31, 2011

F-2

MANAGEMENT’S REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING

The management Arch Western Resources, LLC (the “Company”) is responsible for establishing and maintaining adequate internal control over financial reporting, as defined in Securities Exchange Act Rule 13a-15(f). Under the supervision and with the participation of the Company’s management, including its principal executive officer and principal financial officer, the Company conducted an evaluation of the effectiveness of its internal control over financial reporting based on the criteria set forth in Internal Control — Integrated Framework issued by the Committee of Sponsoring Organizations of the Treadway Commission. Based on its evaluation, management concluded that the Company’s internal control over financial reporting is effective as of December 31, 2010.

This annual report does not include an attestation report of the company’s registered public accounting firm regarding internal control over financial reporting. Management’s report was not subject to attestation by the company’s registered public accounting firm pursuant to rules of the Securities and Exchange Commission that permit the company to provide only management’s report in this annual report.


-s- Paul A. Lang		-s- John T. Drexler
Paul A. Lang		John T. Drexler
President and Principal		Senior Vice President and Chief
Executive Officer		Financial Officer

F-3

ARCH WESTERN RESOURCES, LLC AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF INCOME


	Year Ended December 31
	2010			2009			2008
	(In thousands)
Revenues
Coal sales	$	2,048,287		$	1,651,389		$	1,758,008

Costs, expenses and other
Cost of coal sales		1,679,872			1,398,663			1,395,176
Depreciation, depletion and amortization		167,260			159,755			155,400
Amortization of acquired sales contracts, net		35,606			19,623			(705	)
Selling, general and administrative expenses		35,989			44,513			31,940
Other operating income, net		(4,789	)		(10,475	)		(4,195	)

		1,913,938			1,612,079			1,577,616


Income from operations		134,349			39,310			180,392

Interest income (expense), net
Interest expense		(61,614	)		(67,605	)		(66,556	)
Interest income, primarily from Arch Coal, Inc.		52,444			46,571			74,869

		(9,170	)		(21,034	)		8,313

Other non-operating expense
Loss on early extinguishment of debt		(6,776	)		—			—

		(6,776	)		—			—


Net income	$	118,403		$	18,276		$	188,705

Net income attributable to redeemable membership interest	$	537		$	10		$	872
Net income attributable to non-redeemable membership interest	$	117,866		$	18,266		$	187,833

The accompanying notes are an integral part of the consolidated financial statements.

F-4

ARCH WESTERN RESOURCES, LLC AND SUBSIDIARIES

CONSOLIDATED BALANCE SHEETS


	December 31
	2010			2009
	(In thousands)
ASSETS
Current assets
Cash and cash equivalents	$	79,817		$	6,819
Receivables		2,015			8,379
Receivable from Arch Coal, Inc.		582,384			—
Inventories		150,419			165,650
Other		21,435			23,350

Total current assets		836,070			204,198

Property, plant and equipment
Coal lands and mineral rights		763,059			763,059
Plant and equipment		1,665,285			1,589,858
Deferred mine development		548,776			526,551

		2,977,120			2,879,468
Less accumulated depreciation, depletion and amortization		(1,488,277	)		(1,331,168	)

Property, plant and equipment, net		1,488,843			1,548,300
Other assets
Receivable from Arch Coal, Inc.		910,797			1,541,243
Other		10,920			14,172

Total other assets		921,717			1,555,415

Total assets	$	3,246,630		$	3,307,913

LIABILITIES AND MEMBERSHIP INTERESTS
Current liabilities
Accounts payable	$	121,670		$	74,508
Accrued expenses and other current liabilities		153,141			144,432
Commercial paper		56,904			49,452

Total current liabilities		331,715			268,392
Long-term debt		451,618			954,782
Note payable to Arch Coal, Inc.		225,000			—
Asset retirement obligations		301,355			274,914
Accrued postretirement benefits other than pension		23,509			28,819
Accrued pension benefits		23,904			34,523
Accrued workers’ compensation		6,102			4,067
Other noncurrent liabilities		36,913			26,744

Total liabilities		1,400,116			1,592,241
Redeemable membership interest		10,444			8,962

Non-redeemable membership interest		1,836,070			1,706,710

Total liabilities and membership interests	$	3,246,630		$	3,307,913

The accompanying notes are an integral part of the consolidated financial statements.

F-5

ARCH WESTERN RESOURCES, LLC AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF CASH FLOWS


	Year Ended December 31
	2010			2009			2008
	(In thousands)
Operating Activities
Net income	$	118,403		$	18,276		$	188,705
Adjustments to reconcile net income to cash provided by operating activities
Depreciation, depletion and amortization		167,260			159,755			155,400
Amortization of acquired sales contracts, net		35,606			19,623			(705	)
Amortization of debt financing costs		2,067			2,330			2,421
Loss on early extinguishment of debt		6,776			—			—
Changes in operating assets and liabilities
Receivables		6,364			(5,115	)		629
Inventories		15,230			(11,233	)		7,900
Accounts payable and accrued expenses		54,378			(32,439	)		16,505
Accrued postretirement benefits other than pension		1,087			2,938			3,299
Asset retirement obligations		22,610			18,328			16,480
Accrued workers’ compensation		(141	)		378			192
Other		8,736			5,278			5,756

Cash provided by operating activities		438,376			178,119			396,582


Investing Activities
Capital expenditures		(102,612	)		(125,454	)		(286,607	)
Change in receivable from Arch Coal, Inc.		12,803			(32,784	)		(100,391	)
Proceeds from dispositions of property, plant and equipment		79			91			378
Additions to prepaid royalties		(2,974	)		(2,791	)		(535	)
Reimbursement of deposits on equipment		—			3,209			2,697

Cash used in investing activities		(92,704	)		(157,729	)		(384,458	)


Financing Activities
Repayment of long-term debt, including redemption premium		(505,627	)		—			—
Loan from Arch Coal, Inc.		225,000			—			—
Net proceeds from (repayments on) commercial paper		7,452			(16,219	)		(9,288	)
Debt financing costs		(390	)		(203	)		(233	)
Contribution from redeemable membership interest		891			—			—


Cash used in financing activities		(272,674	)		(16,422	)		(9,521	)

Increase in cash and cash equivalents		72,998			3,968			2,603
Cash and cash equivalents, beginning of year		6,819			2,851			248

Cash and cash equivalents, end of year	$	79,817		$	6,819		$	2,851


Supplemental cash flow information:
Cash paid during the year for interest, net of amounts capitalized	$	71,600		$	65,626		$	58,478

The accompanying notes are an integral part of the consolidated financial statements.

F-6

ARCH WESTERN RESOURCES, LLC AND SUBSIDIARIES

CONSOLIDATED STATEMENTS OF NON-REDEEMABLE MEMBERSHIP INTEREST
Three years ended December 31, 2010


	Non-redeemable
	Membership
	Interest
	(In thousands)
Balance at January 1, 2008	$	1,330,202
Comprehensive income
Net income		187,833
Pension, postretirement and other post-employment benefits adjustment		(22,000	)
Net pension, postretirement and other post-employment benefits adjustments reclassified to income		(327	)

Total comprehensive income		165,506
Dividends on preferred membership interest		(95	)


Balance at December 31, 2008		1,495,613
Comprehensive income
Net income		18,266
Pension, postretirement and other post-employment benefits adjustment		14,998
Net pension, postretirement and other post-employment benefits adjustments reclassified to income		(161	)

Total comprehensive income		33,103
Reclassification of prior contribution		(121	)
Contribution of former Jacob’s Ranch mining complex net assets from Arch Coal		178,210
Dividends on preferred membership interest		(95	)


Balance at December 31, 2009		1,706,710
Comprehensive income
Net income		117,866
Pension, postretirement and other post-employment benefits adjustment		13,282
Net pension, postretirement and other post-employment benefits adjustments reclassified to income		(1,693	)

Total comprehensive income		129,455
Dividends on preferred membership interest		(95	)


Balance at December 31, 2010	$	1,836,070

The accompanying notes are an integral part of the consolidated financial statements.

F-7

ARCH WESTERN RESOURCES, LLC AND SUBSIDIARIES

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Formation of the Company

On June 1, 1998, Arch Coal, Inc. (“Arch Coal”) acquired the Colorado and Utah coal operations of Atlantic Richfield Company (“ARCO”) and simultaneously combined the acquired ARCO operations and Arch Coal’s Wyoming operation with ARCO’s Wyoming operations in a new joint venture named Arch Western Resources, LLC (the “Company”). ARCO was acquired by BP p.l.c. (formerly BP Amoco) in 2000. Arch Coal has a 99.5% common membership interest in the Company, while BP p.l.c. has a 0.5% common membership interest and a preferred membership interest in the Company. Net profits and losses are allocated only to the common membership interests on the basis of 99.5% to Arch Coal and 0.5% to BP p.l.c. In accordance with the membership agreement of the Company, no profit or loss is allocated to the preferred membership interest of BP p.l.c. Except for a preferred return, distributions to members are allocated on the basis of 99.5% to Arch Coal and 0.5% to BP p.l.c. The preferred return entitles BP p.l.c. to receive an annual distribution from the common membership interests equal to 4% of the preferred capital account balance at the end of the year. The preferred return is payable at the Company’s discretion.

In connection with the formation of the Company, Arch Coal agreed to indemnify BP p.l.c. against certain tax liabilities in the event that such liabilities arise as a result of certain actions taken by Arch Coal or the Company prior to June 1, 2013. The provisions of the indemnification agreement may restrict the Company’s ability to sell or dispose of certain properties, repurchase certain of its equity interests or reduce its indebtedness.

On October 1, 2009, Arch Coal contributed to the Company the employees, inventories and supply parts, equipment and other personal property of the former Jacobs Ranch mining complex, which was adjacent to the Company’s Black Thunder mining operations. The contributed assets and related liabilities were immediately merged with the Black Thunder mining operations. The Company is leasing the related coal reserves of approximately 345 million tons from a subsidiary of Arch Coal.

2. Accounting Policies

Basis of Presentation

The consolidated financial statements include the accounts of the Company and its subsidiaries and controlled entities. Intercompany transactions and accounts have been eliminated in consolidation. The Company’s business is the production of steam coal from surface and underground mines primarily for sale to utilities. The Company’s mines are located in Wyoming, Colorado and Utah. The Company’s results of operations reflect all costs of doing business, including expenses incurred on the Company’s behalf by Arch Coal. Certain assets, such as coal reserves and acquired sales contracts, may be owned by and reflected in the financial statements of Arch Coal, but the cost representing the usage of those assets is reflected in the results of operations of the Company. In addition, there is goodwill of $114.9 million on the consolidated balance sheet of Arch Coal that is associated with the Company’s Black Thunder mining complex for Arch Coal’s impairment testing purposes.

Accounting Pronouncements Adopted

There were no accounting pronouncements whose adoption had a material impact on the Company’s consolidated financial statements.

Accounting Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents are stated at cost. Cash equivalents consist of highly-liquid investments with an original maturity of three months or less when purchased.

F-8

Inventories

Coal and supplies inventories are valued at the lower of average cost or market. Coal inventory costs include labor, supplies, equipment costs, transportation costs prior to title transfer to customers and operating overhead. Stripping costs incurred during the production phase of the mine are considered variable production costs and are included in the cost of coal extracted during the period the stripping costs are incurred.

Acquired Sales Contracts

Coal supply agreements (sales contracts) acquired in a business combination are capitalized at their fair value and amortized over the tons of coal shipped during the term of the contract. The fair value of sales contracts are determined by discounting the cash flows attributable to the difference between the contract price and the prevailing forward prices for the tons under contract at the date of acquisition. Sales contracts associated with the acquisition of the Jacob’s Ranch mining complex were not contributed to the Company, however, the amortization of these acquired sales contracts is reflected in the accompanying consolidated statement of income. Based upon expected shipments under these contracts, the Company anticipates annual amortization expense (income) of acquired sales contracts in the next five years of: $19.9 million, $0.4 million, $(4.7) million, $(4.7) million and $(4.7) million.

Property, Plant and Equipment

Plant and Equipment

Plant and equipment are recorded at cost. Interest costs applicable to major asset additions are capitalized during the construction period. For the year ended December 31, 2010 no interest costs were capitalized. During the years ended December 31, 2009 and 2008 interest costs of $0.8 million and $11.7 million, respectively, were capitalized. Expenditures that extend the useful lives of existing plant and equipment or increase the productivity of the asset are capitalized. The cost of maintenance and repairs that do not extend the useful life or increase the productivity of the asset are expensed as incurred. Preparation plants and loadouts are depreciated using the units-of-production method over the estimated recoverable reserves, subject to a minimum level of depreciation. Other plant and equipment are depreciated principally on the straight-line method over the estimated useful lives of the assets, limited by the remaining life of the mine. The useful lives of mining equipment, including longwalls, draglines and shovels, range from 5 to 32 years. The useful lives of buildings and leasehold improvements generally range from 10 to 30 years.

Deferred Mine Development

Costs of developing new mines or significantly expanding the capacity of existing mines are capitalized and amortized using the units-of-production method over the estimated recoverable reserves that are associated with the property benefited. Costs may include construction permits and licenses; mine design; construction of access roads, shafts, slopes and main entries; and removing overburden to access reserves in a new pit. Additionally, deferred mine development includes the costs associated with asset retirement obligations.

Coal Lands and Mineral Rights

A significant portion of the Company’s coal reserves are controlled through leasing arrangements, primarily with Arch Coal. The net book value of the Company’s leased coal interests was $339.9 million and $353.7 million at December 31, 2010 and 2009, respectively. Any amounts paid to acquire coal reserves are capitalized and depleted over the life of proven and probable reserves. Coal lease rights are depleted using the units-of-production method, and the rights are assumed to have no residual value. The leases are generally long-term in nature (original terms range from 10 to 50 years), and substantially all of the leases contain provisions that allow for automatic extension of the lease term providing certain requirements are met.

F-9

Impairment

If facts and circumstances suggest that a long-lived asset or asset group may not be recoverable, the asset or asset group is reviewed for potential impairment. If this review indicates that the carrying amount of the asset will not be recoverable through projected undiscounted cash flows related to the asset over its remaining life, then an impairment loss is recognized by reducing the carrying value of the asset to its fair value.

Deferred Financing Costs

The Company capitalizes costs incurred in connection with new borrowings, the establishment or enhancement of credit facilities and issuance of debt securities. These costs are amortized as an adjustment to interest expense over the life of the borrowing or term of the credit facility using the interest method. The unamortized balance of deferred financing costs was $2.7 million and $7.6 million at December 31, 2010 and 2009, respectively. Amounts classified as current were $1.1 million and $2.2 million at December 31, 2010 and 2009, respectively. Current amounts are recorded in other current assets and noncurrent amounts are recorded in other assets in the accompanying consolidated balance sheets.

Revenue Recognition

Coal sales revenues include sales to customers of coal produced at Company operations. The Company recognizes revenue from coal sales at the time risk of loss passes to the customer at contracted amounts. Transportation costs are included in cost of coal sales and amounts billed by the Company to its customers for transportation are included in coal sales.

Other Operating Income, Net

Other operating income in the accompanying consolidated statements of income reflects income and expense from sources other than coal sales.

Asset Retirement Obligations

The Company’s legal obligations associated with the retirement of long-lived assets are recognized at fair value at the time the obligations are incurred. Accretion expense is recognized through the expected settlement date of the obligation. Obligations are incurred at the time development of a mine commences for underground and surface mines or construction begins for support facilities, refuse areas and slurry ponds. The obligation’s fair value is determined using discounted cash flow techniques and is based upon permit requirements and various estimates and assumptions that would be used by market participants, including estimates of disturbed acreage, reclamation costs and assumptions regarding productivity. Upon initial recognition of a liability, a corresponding amount is capitalized as part of the carrying value of the related long-lived asset. Amortization of the related asset is recorded on a units-of-production basis over the mine’s estimated recoverable reserves. Any difference between the recorded obligation and the actual cost of reclamation is recorded in profit or loss in the period the obligation is settled. See additional discussion in Note 10, “Asset Retirement Obligations.”

Income Taxes

The financial statements do not include a provision for income taxes as the Company is treated as a partnership for income tax purposes and does not incur federal or state income taxes. Instead, its earnings and losses are included in the members’ separate income tax returns.

Related Party Transactions

Transactions with Arch Coal may not be at arms length. If the transactions were negotiated with an unrelated party, the impact could be material to the Company’s results of operations. See Note 11, “Related Party Transactions” for discussion of various transactions with Arch Coal.

Benefit Plans

Essentially all of the Company’s employees are covered by Arch Coal’s non-contributory defined benefit pension plan. The benefits are based on the employee’s age and compensation. The Company also provides certain postretirement medical and life

F-10

insurance benefits for eligible employees under Arch Coal’s plans. The Company reflects its actuarially-determined allocation of benefit cost, benefit obligation and other comprehensive income related to these plans in its consolidated financial statements. See further discussion in Note 9, “Employee Benefit Plans.”

Accounting Standards Issued and Not Yet Adopted

There are no new accounting pronouncements that have been issued whose adoption is expected to have a material impact on the Company’s consolidated financial statements.

3. Redeemable Membership Interest

The terms of the Company’s membership agreement grant a put right to BP p.l.c., where BP p.l.c. may require Arch Coal to purchase its membership interest. The terms of the agreement state that the price of the membership interest shall be determined by mutual agreement between the members. In the absence of an agreed-upon price, the price is equal to the sum of the preferred membership interest of $2.4 million and BP p.l.c.’s common membership interest, as defined in the agreement. In addition, Arch Coal has a call right, which allows Arch Coal to purchase BP p.l.c.’s members’ interest as long as it pays damages as set forth in the agreement between the members. It is the members’ intention at this point to continue the joint venture.

The following table presents the components of and changes in BP p.l.c.’s membership interest:


						Total
	Common			Preferred		Redeemable
	Membership			Membership		Membership
	Interest			Interest		Interest
	(In thousands)
Balance at January 1, 2008	$	5,601		$	2,399	$	8,000
Net income attributable to BP p.l.c. common membership interest		872			—		872
Other comprehensive income attributable to BP p.l.c. common membership interest		(103	)		—		(103	)
Other		(3	)		—		(3	)
Dividends on preferred membership interest		(1	)		—		(1	)

Balance at December 31, 2008		6,366			2,399		8,765

Net income attributable to BP p.l.c. common membership interest		10			—		10
Other comprehensive income attributable to BP p.l.c. common membership interest		67			—		67
Reclassification of prior contribution		121			—		121
Dividends on preferred membership interest		(1	)		—		(1	)

Balance at December 31, 2009		6,563			2,399		8,962

Net income attributable to BP p.l.c. common membership interest		537			—		537
Other comprehensive income attributable to BP p.l.c. common membership interest		55			—		55
BP p.l.c’s contribution related to Jacobs Ranch		891			—		891
Dividends on preferred membership interest		(1	)		—		(1	)

Balance at December 31, 2010	$	8,045		$	2,399	$	10,444

4. Accumulated Other Comprehensive Income (Loss)

Other comprehensive income (loss) items are transactions recorded in membership interests during the year, excluding net income and transactions with members. Following are the items included in accumulated other comprehensive income (loss):


	Accumulated Other
	Comprehensive
	Income (Loss)
	(In thousands)
Balance at January 1, 2008	$	(2,245	)
Pension, postretirement and other post-employment benefits		(22,433	)

Balance at December 31, 2008		(24,678	)
Pension, postretirement and other post-employment benefits		14,903

Balance at December 31, 2009		(9,775	)
Pension, postretirement and other post-employment benefits		11,645

Balance at December 31, 2010	$	1,870

F-11

The net accumulated loss that will be reclassified from accumulated other comprehensive income into net income 2011 is $0.4 million.

5. Inventories

Inventories consist of the following:


	December 31
	2010		2009
	(In thousands)
Coal	$	46,464	$	42,316
Repair parts and supplies, net of allowance		103,955		123,334

	$	150,419	$	165,650

The repair parts and supplies are stated net of an allowance for slow-moving and obsolete inventories of $11.7 million and $12.6 million at December 31, 2010 and 2009, respectively.

6. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consists of the following:


	December 31
	2010		2009
	(In thousands)
Payroll and employee benefits	$	24,971	$	23,841
Taxes		98,914		79,735
Interest		17,189		32,105
Other		12,067		8,751

	$	153,141	$	144,432

7. Debt and Financing Arrangements

Refinancing of senior notes

On September 8, 2010, the Company redeemed $500.0 million aggregate principal amount of the outstanding 6.75% senior notes at a redemption price of 101.125%. The Company funded this redemption with cash transferred from Arch Coal in the form of a loan of $225.0 million and a repayment of a portion of the note receivable from Arch Coal. The Company recognized a loss on the redemption of $6.8 million, including the payment of the $5.6 million redemption premium and the write-off of $3.3 million of unamortized debt financing costs, partially offset by the write-off of $2.1 million of the original issue premium on the 6.75% senior notes.

The loan was made pursuant to an intercompany credit agreement with Arch Coal. Under the intercompany credit agreement, the Company may borrow up to $675.0 million through July 1, 2013, or such later date as designated by Arch Coal. Interest on loans outstanding under the agreement is calculated at a per annum rate equal to the three month LIBOR rate plus 200 or 250 basis points, depending on the Company’s leverage ratio, as defined in the agreement, at the date the rate is determined. As of December 31, 2010 the interest rate on the loan was 2.79%. Interest is due on any outstanding loans on the first day of each calendar quarter. The Company may repay the balance of the loan at any time, in whole or in part, without penalty. It is currently management’s intention not to prepay the balance of the loan within the next year. Therefore, the loan is classified on the accompanying consolidated balance sheets as noncurrent.

6.75% senior notes

The 6.75% senior notes, due July 1, 2013, were issued by the Company’s subsidiary, Arch Western Finance LLC (“Arch Western Finance”), under an indenture dated June 25, 2003. The senior notes are guaranteed by Arch Western and certain of its subsidiaries and are secured by an intercompany note from Arch Coal. The terms of the senior notes contain restrictive covenants that limit Arch Western’s ability to, among other things, incur additional debt, sell or transfer assets, pay dividends and make certain investments. Of the aggregate principal outstanding at December 31, 2010 and 2009, $118.4 million and $250.0 million, respectively, of the 6.75% notes were issued at a premium of 104.75% of par. The premium is being amortized over the life of the notes. Interest is payable on the notes on January 1 and July 1 of each year. The redemption price of the notes, reflected as a percentage of the principal amount, is 101.125%

F-12

for notes redeemed before July 1, 2011 and 100% for notes redeemed on or after July 1, 2011.

Commercial paper

On August 15, 2007, the Company entered into a commercial paper placement program, as amended, to provide short-term financing. Under the commercial paper program, the Company may sell interest-bearing or discounted short-term unsecured debt obligations with maturities of no more than 270 days. Market conditions have impacted the Company’s ability to issue commercial paper, and the Company amended the program on March 25, 2010 to decrease the maximum aggregate principal amount of the program to $75 million from $100 million. The commercial paper program is supported by a revolving credit facility, which is subject to renewal annually and expires on April 30, 2011. As of December 31, 2010, the weighted-average interest rate of the Company’s outstanding commercial paper was 1.45% and maturity dates ranged from 3 to 55 days.

8. Fair Values of Financial Instruments

The following methods and assumptions were used by the Company in estimating its fair value disclosures for financial instruments:

Cash and cash equivalents: At December 31, 2010 and 2009, the carrying amounts of cash and cash equivalents approximate fair value.

Debt: The fair value of the Company’s debt, including commercial paper and excluding intercompany debt, was $512.5 million and $992.3 million at December 31, 2010 and 2009, respectively. Fair values are based upon observed prices in an active market when available or from valuation models using market information.

9. Employee Benefit Plans

Defined Benefit Pension and Other Postretirement Benefit Plans

Essentially all of the Company’s employees are covered by Arch Coal’s defined benefit pension plan. The benefits are based on the employee’s age and compensation. Arch Coal funds the plans in an amount not less than the minimum statutory funding requirements or more than the maximum amount that can be deducted for federal income tax purposes. Arch Coal allocates a portion of the funding to the Company, which is charged to the intercompany receivable. See Note 11, “Related Party Transactions” for further discussion.

The Company also provides certain postretirement medical/life insurance benefits for eligible employees under Arch Coal’s plans. Generally, covered employees who terminate employment after meeting eligibility requirements are eligible for postretirement coverage for themselves and their dependents. The employee postretirement medical/life plans are contributory, with retiree contributions adjusted periodically, and contain other cost-sharing features such as deductibles and coinsurance. Arch Coal allocates a portion of the funding to the Company, which is charged to the intercompany receivable as benefits are paid.

The Company’s allocated expense related to these plans was $9.6 million, $12.6 million and $11.6 million for the years ended December 31, 2010, 2009 and 2008, respectively. The Company’s balance sheet reflects its allocated portion of Arch Coal’s liabilities related to its benefit plans, including amounts recorded through other comprehensive income. The Company’s recorded balance sheet amounts are as follows:


	December 31
	2010			2009
	(In thousands)
Accrued benefit liabilities (current)	$	1,230		$	1,250
Accrued benefit liabilities (noncurrent)		47,413			63,342
Accumulated other comprehensive loss		(21	)		(14,647	)

F-13

Other Plans

Arch Coal sponsors savings plans which were established to assist eligible employees in providing for their future retirement needs. The Company’s expense related to the plans were $11.4 million in 2010, $9.5 million in 2009 and $9.7 million in 2008.

10. Asset Retirement Obligations

The Company’s asset retirement obligations arise from the Federal Surface Mining Control and Reclamation Act of 1977 and similar state statutes, which require that mine property be restored in accordance with specified standards and an approved reclamation plan. The required reclamation activities to be performed are outlined in the Company’s mining permits. These activities include reclaiming the pit and support acreage at surface mines, sealing portals at underground mines, and reclaiming refuse areas and slurry ponds.

The Company reviews its asset retirement obligation at least annually and makes necessary adjustments for permit changes as granted by state authorities and for revisions of estimates of the amount and timing of costs. For ongoing operations, adjustments to the liability result in an adjustment to the corresponding asset. For idle operations, adjustments to the liability are recognized as income or expense in the period the adjustment is recorded.

The following table describes the changes to the Company’s asset retirement obligations for the years ended December 31:


	2010			2009
	(In thousands)
Balance at January 1 (including current portion)	$	277,088		$	228,203
Accretion expense		23,952			20,957
Additions resulting from acquisition of Jacobs Ranch		—			75,109
Adjustments to the liability from changes in estimates		8,831			(45,254	)
Liabilities settled		(1,476	)		(1,927	)

Balance at December 31		308,395			277,088
Current portion included in accrued expenses		(7,040	)		(2,174	)

Noncurrent liability	$	301,355		$	274,914

The reduction in the liability of $45.3 million in 2009 resulted from changes to the Black Thunder mine’s pit configuration upon the integration of the Jacobs Ranch mining operations.

As of December 31, 2010, the Company had $33.2 million in surety bonds outstanding and $403.4 million in self-bonding to secure reclamation obligations.

11. Related Party Transactions

The Company’s cash transactions are managed by Arch Coal. Cash paid to or from the Company that is not considered a distribution or a contribution is recorded in an Arch Coal receivable account. In addition, any amounts owed between the Company and Arch Coal, exclusive of borrowings under the intercompany credit agreement discussed in Note 7, “Debt and Financing Arrangements”, are recorded in the account. At December 31, 2010 and 2009, the receivable from Arch Coal was approximately $1.5 billion. This amount earns interest from Arch Coal at the prime interest rate. Interest earned for the years ended December 31, 2010, 2009 and 2008 was $52.2 million, $46.5 million and $74.6 million, respectively. The current portion of the receivable balance at December 31, 2010 represents the amount needed to fund working capital and contractual purchase, service and lease obligations due within the next twelve months.

As mentioned in Note 7, “Debt and Financing Arrangements”, during September of 2010, the Company received a loan of $225.0 million and a repayment of a portion of the balance receivable from Arch Coal to redeem $500.0 million aggregate principal amount of the outstanding 6.75% senior notes at a redemption price of 101.125%. Interest incurred on the loan was $1.9 million for the year ended December 31, 2010.

On February 10, 2006, Arch Coal established an accounts receivable securitization program. Under the program, the Company sells its receivables to Arch Coal without recourse at a discount based on the prime rate and days sales outstanding. During 2010, 2009 and 2008, the Company sold $1.7 billion, $1.4 billion and $1.7 billion of trade accounts receivable to Arch Coal, respectively, at a discount of $4.0 million, $3.5 million and $7.1 million, respectively.

F-14

The Company mines on tracts that are owned or leased by Arch Coal and subleased to the Company. The Company had approximately 1.6 billion tons of reserves under lease with Arch Coal at December 31, 2010. Royalties on all properties leased from Arch Coal are 7.0% of the value of the coal mined and removed from the leased land, pursuant to Federal coal regulations, plus all rents and royalties (excluding bonus bid obligations) due under Arch Coal’s subsidiary’s state and federal lease agreements. No advance royalties are required under the agreements. For the years ended December 31, 2010, 2009 and 2008, the Company incurred production royalties of $92.4 million, $47.8 million and $35.8 million, respectively, under sublease agreements with Arch Coal.

Amounts charged to the intercompany account for the Company’s allocated portion of contributions to Arch Coal’s pension and postretirement plans totaled $10.9 million, $11.1million and $1.1 million for the years ended December 31, 2010, 2009 and 2008, respectively.

The Company is charged selling, general and administrative services fees by Arch Coal. Expenses are allocated based on Arch Coal’s best estimates of proportional or incremental costs, whichever is more representative of costs incurred by Arch Coal on behalf of the Company. Amounts allocated to the Company by Arch Coal were $36.0 million, $44.5 million and $31.9 million for the years ended December 31, 2010, 2009 and 2008, respectively. Costs allocated in 2009 included costs related to the Jacobs Ranch acquisition. Such amounts are reported as selling, general and administrative expenses in the accompanying consolidated statements of income.

12. Concentration of Credit Risk and Major Customers

The Company markets its coal principally to electric utilities in the United States. Arch Coal has a formal written credit policy that establishes procedures to determine creditworthiness and credit limits for trade customers. Generally, credit is extended based on an evaluation of the customer’s financial condition. Collateral is not generally required, unless credit cannot be established. Credit losses are provided for in the financial statements and historically have been minimal.

The Company is committed under long-term contracts to supply coal that meets certain quality requirements at specified prices. These prices are generally adjusted based on indices. Quantities sold under some of these contracts may vary from year to year within certain limits at the option of the customer. The Company and its operating subsidiaries sold approximately 144.0 million tons of coal in 2010. Approximately 81% of this tonnage (representing approximately 82% of the Company’s revenue) was sold under long-term contracts (contracts having a term of greater than one year). Long-term contracts range in remaining life from one to seven years. Some of these contracts include pricing which is above current market prices. Sales (including spot sales) to significant customers were as follows:


	Year Ended December 31
	2010		2009		2008
			(In thousands)
Tennessee Valley Authority	$	174,360	$	133,455	$	265,937
Ameren		220,937		189,768		170,346

Transportation

The Company depends upon rail, truck and belt transportation systems to deliver coal to its customers. Disruption of these transportation services due to weather-related problems, mechanical difficulties, strikes, lockouts, bottlenecks, and other events could temporarily impair the Company’s ability to supply coal to its customers and result in decreased shipments. In the past, disruptions in rail service have resulted in missed shipments and production interruptions.

13. Leases

The Company leases equipment, land and various other properties under non-cancelable long-term leases, expiring at various dates. Certain leases contain options that would allow the Company to extend the lease or purchase the leased asset at the end of the base lease term. In addition, the Company enters into various non-cancelable royalty lease agreements under which future minimum payments are due.

F-15

Minimum payments due in future years under these agreements in effect at December 31, 2010 are as follows:


	Operating
	Leases		Royalties
	(In thousands)
2011	$	26,351	$	1,170
2012		23,622		1,203
2013		20,269		1,077
2014		18,250		1,025
2015		12,273		882
Thereafter		13,265		5,881

	$	114,030	$	11,238

Rental expense related to these operating leases amounted to $32.3 million in 2010, $33.5 million in 2009 and $32.1 million in 2008. Royalty expense was $322.3 million, $227.6 million and $222.1 million for the years ended December 31, 2010, 2009 and 2008, respectively, including $92.4 million, $47.8 million and $35.8 million, respectively, that were incurred under sublease agreements with Arch Coal. See Note 11, “Related Party Transactions” for further discussion of these agreements.

As of December 31, 2010, certain of the Company’s lease obligations were secured by outstanding surety bonds totaling $19.2 million.

14. Contingencies

The Company is a party to numerous claims and lawsuits with respect to various matters. The Company provides for costs related to contingencies when a loss is probable and the amount is reasonably determinable. After conferring with counsel, it is the opinion of management that the ultimate resolution of pending claims will not have a material adverse effect on the consolidated financial condition, results of operations or liquidity of the Company.

15. Segment Information

The Company has two reportable business segments, which are based on the major low-sulfur coal basins in which the Company operates. Both of these reportable business segments include a number of mine complexes. The Company manages its coal sales by coal basin, not by individual mine complex. Geology, coal transportation routes to customers, regulatory environments and coal quality are generally consistent within a basin. Accordingly, market and contract pricing have developed by coal basin. Mine operations are evaluated based on their per-ton operating costs (defined as including all mining costs but excluding pass-through transportation expenses), as well as on other non-financial measures, such as safety and environmental performance. The Company’s reportable segments are the Powder River Basin (PRB) segment, with operations in Wyoming, and the Western Bituminous (WBIT) segment, with operations in Utah, Colorado and southern Wyoming.

Operating segment results for the years ended December 31, 2010, 2009 and 2008 are presented below. Results for the operating segments include all direct costs of mining. Corporate, Other and Eliminations includes primarily corporate overhead and other support functions.

F-16

The amounts in total assets below represent an represent an allocation of assets used in the segments’ cash-generating activities. The amounts in the Corporate, Other and Eliminations represent primarily intercompany receivables.


						Corporate,
						Other and
	PRB		WBIT			Eliminations			Consolidated
	(In thousands)
December 31, 2010
Coal sales	$	1,510,825	$	537,462		$	—		$	2,048,287
Income from operations		108,710		58,740			(33,101	)		134,349
Total assets		1,064,879		649,843			1,531,908			3,246,630
Depreciation, depletion and amortization		88,784		78,476			—			167,260
Amortization of acquired sales contracts, net		35,606		—			—			35,606
Capital expenditures		37,141		65,470			—			102,611
December 31, 2009
Coal sales	$	1,112,371	$	539,018		$	—		$	1,651,389
Income from operations		45,463		31,472			(37,625	)		39,310
Total assets		1,051,007		693,972			1,562,934			3,307,913
Depreciation, depletion and amortization		78,174		81,581			—			159,755
Amortization of acquired sales contracts, net		19,934		(311	)					19,623
Capital expenditures		58,155		67,299			—			125,454
December 31, 2008
Coal sales	$	1,104,393	$	653,615		$	—		$	1,758,008
Income from operations		88,091		123,116			(30,815	)		180,392
Total assets		871,482		691,692			1,541,910			3,105,084
Depreciation, depletion and amortization		74,190		81,210			—			155,400
Amortization of acquired sales contracts, net		336		(1,041	)		—			(705	)
Capital expenditures		123,909		162,698			—			286,607

Reconciliation of income from operations to net income:


	Year Ended December 31
	2010			2009			2008
	(In thousands)
Income from operations	$	134,349		$	39,310		$	180,392
Interest expense		(61,614	)		(67,605	)		(66,556	)
Interest income		52,444			46,571			74,869
Loss on early extinguishment of debt		(6,776	)		—			—

Net income	$	118,403		$	18,276		$	188,705

16. Supplemental Condensed Consolidating Financial Information

Pursuant to the indenture governing the Arch Western Finance senior notes, certain wholly-owned subsidiaries of the Company have fully and unconditionally guaranteed the senior notes on a joint and several basis. The following tables present condensed consolidating financial information for (i) the Company, (ii) the issuer of the senior notes (Arch Western Finance, LLC, a wholly-owned subsidiary of the Company), (iii) the Company’s wholly-owned subsidiaries (Thunder Basin Coal Company, LLC, Mountain Coal Company, LLC, and Arch of Wyoming, LLC), on a combined basis, which are guarantors under the Notes, and (iv) the Company’s majority-owned subsidiary, Canyon Fuel, which is not a guarantor under the Notes.

F-17

Condensed Consolidating Statements of Income
Year Ended December 31, 2010
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Eliminations			Consolidated
Coal sales	$	—		$	—		$	1,679,460		$	368,827		$	—		$	2,048,287
Cost of coal sales		(2,422	)		—			1,394,853			290,005			(2,564	)		1,679,872
Depreciation, depletion and amortization		—			—			119,109			48,151			—			167,260
Amortization of acquired sales contracts, net		—			—			35,606			—			—			35,606
Selling, general and administrative expenses		35,989			—			—			—			—			35,989
Other operating income, net		(467	)		—			(3,178	)		(3,708	)		2,564			(4,789	)

		33,100			—			1,546,390			334,448			—			1,913,938
Income from investment in subsidiaries		158,865			—			—			—			(158,865	)		—

Income from operations		125,765			—			133,070			34,379			(158,865	)		134,349
Interest expense		(59,435	)		(54,280	)		—			(774	)		52,875			(61,614	)
Interest income		52,073			52,875			288			83			(52,875	)		52,444

		(7,362	)		(1,405	)		288			(691	)		—			(9,170	)

Other non-operating expenses
Loss on early extinguishment of debt		—			(6,776	)		—			—			—			(6,776	)

Net income (loss)	$	118,403		$	(8,181	)	$	133,358		$	33,688		$	(158,865	)	$	118,403

F-18

Condensed Consolidating Statements of Income
Year Ended December 31, 2009
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Eliminations			Consolidated
Coal sales	$	—		$	—		$	1,252,732		$	398,657		$	—		$	1,651,389
Cost of coal sales		647			—			1,102,788			298,240			(3,012	)		1,398,663
Depreciation, depletion and amortization		—			—			103,161			56,594			—			159,755
Amortization of acquired sales contracts, net		—			—			19,934			(311	)		—			19,623
Selling, general and administrative expenses		44,513			—			—			—			—			44,513
Other operating income, net		(7,549	)		—			(2,333	)		(3,605	)		3,012			(10,475	)

		37,611			—			1,223,550			350,918			—			1,612,079
Income from investment in subsidiaries		77,243			—			—			—			(77,243	)		—

Income from operations		39,632			—			29,182			47,739			(77,243	)		39,310
Interest expense		(67,666	)		(64,095	)		981			(950	)		64,125			(67,605	)
Interest income		46,310			64,125			30			231			(64,125	)		46,571

		(21,356	)		30			1,011			(719	)		—			(21,034	)

Net income	$	18,276		$	30		$	30,193		$	47,020		$	(77,243	)	$	18,276

F-19

Condensed Consolidating Statements of Income
Year Ended December 31, 2008
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Eliminations			Consolidated
Coal sales	$	—		$	—		$	1,334,332		$	423,676		$	—		$	1,758,008
Cost of coal sales		(1,053	)		—			1,081,271			317,486			(2,528	)		1,395,176
Depreciation, depletion and amortization		—			—			91,200			64,200			—			155,400
Amortization of acquired sales contracts, net		—			—			336			(1,041	)		—			(705	)
Selling, general and administrative expenses		31,940			—			—			—			—			31,940
Other operating income, net		(70	)		—			(3,004	)		(3,649	)		2,528			(4,195	)

		30,817			—			1,169,803			376,996			—			1,577,616
Income from investment in subsidiaries		218,922			—			—			—			(218,922	)		—

Income from operations		188,105			—			164,529			46,680			(218,922	)		180,392
Interest expense		(72,938	)		(53,215	)		(2,823	)		(1,705	)		64,125			(66,556	)
Interest income		73,538			64,125			247			1,084			(64,125	)		74,869

		600			10,910			(2,576	)		(621	)		—			8,313

Net income	$	188,705		$	10,910		$	161,953		$	46,059		$	(218,922	)	$	188,705

F-20

Condensed Consolidating Balance Sheets
December 31, 2010
(in thousands)


	Parent					Guarantor		Non-Guarantor
	Company			Issuer		Subsidiaries		Subsidiaries		Eliminations			Consolidated
Cash and cash equivalents	$	1,613		$	—	$	78,070	$	134	$	—		$	79,817
Receivables		1,033			—		663		319		—			2,015
Receivable from Arch Coal		582,384			—		—		—		—			582,384
Intercompanies		(519,808	)		15,188		341,981		162,639		—			—
Inventories		—			—		104,394		46,025		—			150,419
Other		10,096			1,015		4,129		6,195		—			21,435

Total current assets		75,318			16,203		529,237		215,312		—			836,070

Property, plant and equipment, net		—			—		1,223,493		265,350		—			1,488,843
Investment in subsidiaries		2,789,637			—		—		—		(2,789,637	)		—
Receivable from Arch Coal		888,306			—		—		22,491		—			910,797
Intercompanies		(1,609,147	)		455,401		1,023,119		130,627		—			—
Other		1,402			1,511		3,802		4,205		—			10,920

Total other assets		2,070,198			456,912		1,026,921		157,323		(2,789,637	)		921,717

Total assets	$	2,145,516		$	473,115	$	2,779,651	$	637,985	$	(2,789,637	)	$	3,246,630

Accounts payable	$	2,604		$	—	$	102,290	$	16,776	$	—		$	121,670
Accrued expenses and other current liabilities		5,714			15,188		122,473		9,766		—			153,141
Commercial paper		56,904			—		—		—		—			56,904

Total current liabilities		65,222			15,188		224,763		26,542		—			331,715

Long-term debt		—			451,618		—		—		—			451,618
Note payable to Arch Coal		225,000			—		—		—		—			225,000
Asset retirement obligations		—			—		290,473		10,882		—			301,355
Accrued postretirement benefits other than pension		3,629			—		11,571		8,309		—			23,509
Accrued pension benefits		3,342			—		11,962		8,600		—			23,904
Accrued workers’ compensation		(94	)		—		2,042		4,154		—			6,102
Other noncurrent liabilities		1,903			—		34,930		80		—			36,913

Total liabilities		299,002			466,806		575,741		58,567		—			1,400,116

Redeemable membership interest		10,444			—		—		—		—			10,444
Non-redeemable membership interest		1,836,070			6,309		2,203,910		579,418		(2,789,637	)		1,836,070

Total liabilities and membership interests	$	2,145,516		$	473,115	$	2,779,651	$	637,985	$	(2,789,637	)	$	3,246,630

F-21

Condensed Consolidating Balance Sheets
December 31, 2009
(in thousands)


						Guarantor		Non-Guarantor
	Parent Company			Issuer		Subsidiaries		Subsidiaries		Eliminations			Consolidated
Cash and cash equivalents	$	6,714		$	—	$	61	$	44	$	—		$	6,819
Receivables		5,536			—		2,123		720		—			8,379
Inventories		—			—		127,907		37,743		—			165,650
Other		10,423			2,153		3,892		6,882		—			23,350

Total current assets		22,673			2,153		133,983		45,389		—			204,198


Property, plant and equipment, net		—			—		1,258,695		289,605		—			1,548,300

Investment in subsidiaries		2,621,530			—		—		—		(2,621,530	)		—
Receivable from Arch Coal		1,509,032			—		—		32,211		—			1,541,243
Intercompanies		(2,364,534	)		993,857		1,141,474		229,203		—			—
Other		1,785			5,325		2,543		4,519		—			14,172

Total other assets		1,767,813			999,182		1,144,017		265,933		(2,621,530	)		1,555,415

Total assets	$	1,790,486		$	1,001,335	$	2,536,695	$	600,927	$	(2,621,530	)	$	3,307,913


Accounts payable	$	4,176		$	—	$	55,514	$	14,818	$	—		$	74,508
Accrued expenses and other current liabilities		2,885			32,063		97,649		11,835		—			144,432
Commercial paper		49,452			—		—		—		—			49,452

Total current liabilities		56,513			32,063		153,163		26,653		—			268,392

Long-term debt		—			954,782		—		—		—			954,782
Asset retirement obligations		—			—		264,873		10,041		—			274,914
Accrued postretirement benefits other than pension		6,346			—		14,858		7,615		—			28,819
Accrued pension benefits		11,307			—		16,936		6,280		—			34,523
Accrued workers’ compensation		(1,199	)		—		1,217		4,049		—			4,067
Other noncurrent liabilities		1,847			—		24,864		33		—			26,744

Total liabilities		74,814			986,845		475,911		54,671		—			1,592,241

Redeemable membership interest		8,962			—		—		—		—			8,962
Non-redeemable membership interest		1,706,710			14,490		2,060,784		546,256		(2,621,530	)		1,706,710

Total liabilities and membership interests	$	1,790,486		$	1,001,335	$	2,536,695	$	600,927	$	(2,621,530	)	$	3,307,913

F-22

Condensed Consolidating Statements of Cash Flows
Year Ended December 31, 2010
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Consolidated
Cash provided by (used in) operating activities	$	(40,833	)		(17,626	)	$	418,073		$	78,762		$	438,376
Investing Activities
Capital expenditures		—			—			(78,719	)		(23,893	)		(102,612	)
Change in receivable from Arch Coal		3,083			—			—			9,720			12,803
Proceeds from dispositions of property, plant and equipment		—			—			50			29			79
Additions to prepaid royalties		—			—			(2,509	)		(465	)		(2,974	)

Cash provided by (used in) investing activities		3,083			—			(81,178	)		(14,609	)		(92,704	)

Financing Activities
Repayment of long-term debt, including redemption premium		—			(505,627	)		—			—			(505,627	)
Loan from Arch Coal		225,000			—			—			—			225,000
Net proceeds from commercial paper		7,452			—			—			—			7,452
Debt financing costs		(375	)		(15	)		—			—			(390	)
Contribution from redeemable membership interest		891			—			—			—			891
Transactions with affiliates, net		(200,319	)		523,268			(258,886	)		(64,063	)		—

Cash provided by (used in) financing activities		32,649			17,626			(258,886	)		(64,063	)		(272,674	)

Increase (decrease) in cash and cash equivalents		(5,101	)		—			78,009			90			72,998
Cash and cash equivalents, beginning of period		6,714			—			61			44			6,819

Cash and cash equivalents, end of period	$	1,613		$	—		$	78,070		$	134		$	79,817

F-23

Condensed Consolidating Statements of Cash Flows
Year Ended December 31, 2009
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Consolidated
Cash provided by (used in) operating activities	$	(95,111	)	$	824		$	171,532		$	100,874		$	178,119
Investing Activities
Capital expenditures		—			—			(101,887	)		(23,567	)		(125,454	)
Change in receivable from Arch Coal		(30,440	)		—			—			(2,344	)		(32,784	)
Additions to prepaid royalties		—			—			(2,209	)		(582	)		(2,791	)
Proceeds from dispositions of property, plant and equipment		—			—			66			25			91
Reimbursement of deposits on equipment		—			—			3,209			—			3,209

Cash used in investing activities		(30,440	)		—			(100,821	)		(26,468	)		(157,729	)
Financing Activities
Net repayments on commercial paper		(16,219	)		—			—			—			(16,219	)
Debt financing costs		(188	)		(15	)		—			—			(203	)
Transactions with affiliates, net		145,982			(809	)		(70,734	)		(74,439	)		—

Cash provided by (used in) financing activities		129,575			(824	)		(70,734	)		(74,439	)		(16,422	)

Increase (decrease) in cash and cash equivalents		4,024			—			(23	)		(33	)		3,968
Cash and cash equivalents, beginning of period		2,690			—			84			77			2,851

Cash and cash equivalents, end of period	$	6,714		$	—		$	61		$	44		$	6,819

F-24

Condensed Consolidating Statements of Cash Flows
Year Ended December 31, 2008
(in thousands)


							Guarantor			Non-Guarantor
	Parent Company			Issuer			Subsidiaries			Subsidiaries			Consolidated
Cash provided by (used in) operating activities	$	(21,533	)	$	11,703		$	280,446		$	125,966		$	396,582
Investing Activities
Capital expenditures		—			—			(257,029	)		(29,578	)		(286,607	)
Increase in receivable from Arch Coal		(99,311	)		—			(112	)		(968	)		(100,391	)
Proceeds from dispositions of property, plant and equipment		—			—			355			23			378
Additions to prepaid royalties		—			—			—			(535	)		(535	)
Reimbursement of deposits on equipment		—			—			2,697			—			2,697

Cash used in investing activities		(99,311	)		—			(254,089	)		(31,058	)		(384,458	)
Financing Activities
Net repayments on commercial paper		(9,288	)		—			—			—			(9,288	)
Debt financing costs		(219	)		(14	)		—			—			(233	)
Transactions with affiliates, net		132,963			(11,689	)		(26,289	)		(94,985	)		—

Cash provided by (used in) financing activities		123,456			(11,703	)		(26,289	)		(94,985	)		(9,521	)

Increase (decrease) in cash and cash equivalents		2,612			—			68			(77	)		2,603
Cash and cash equivalents, beginning of period		78			—			16			154			248

Cash and cash equivalents, end of period	$	2,690		$	—		$	84		$	77		$	2,851

F-25

ARCH WESTERN RESOURCES, LLC

SCHEDULE II — VALUATION AND QUALIFYING ACCOUNTS


			Additions
			Charged to
	Balance at		Costs		Charged to				Balance at
	Beginning of Year		and Expenses		Other Accounts		Deductions(a)		End of Year
	(In thousands)
Year Ended Dec. 31, 2010
Reserves deducted from asset accounts
Other assets — other notes and accounts receivable	$	—	$	—	$	—	$	—	$	—
Current assets — repair parts and supplies inventories		12,583		1,774		—		2,630		11,727
Year Ended Dec. 31, 2009
Reserves deducted from asset accounts
Other assets — other notes and accounts receivable	$	—	$	—	$	—	$	—	$	—
Current assets — repair parts and supplies inventories		11,987		1,210		—		612		12,583
Year Ended Dec. 31, 2008
Reserves deducted from asset accounts
Other assets — other notes and accounts receivable	$	—	$	—	$	—	$	—	$	—
Current assets — repair parts and supplies inventories		12,497		1,492		—		2,002		11,987


(a)		Reserves utilized, unless otherwise indicated.

F-26

Signatures

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

			Arch Western Resources, LLC

			/s/ Paul A. Lang
			Paul A. Lang
			President
			March 31, 2011

KNOW ALL PERSONS BY THESE PRESENTS: That each of the undersigned member and officers of Arch Western Resources, LLC, a Delaware limited liability company, hereby constitutes and appoints Robert G. Jones and Jon S. Ploetz, and each of them, its or his true and lawful attorney-in-fact and agent, with full power to act without the other, to sign Arch Western Resources, LLC’s Annual Report on Form 10-K for the year ended December 31, 2010, to be filed with the Securities and Exchange Commission under the provisions of the Securities Exchange Act of 1934, as amended; to file such Annual Report and the exhibits thereto and any and all other documents in connection therewith, including without limitation, amendments thereto, with the Securities and Exchange Commission; and to do and perform any and all other acts and things requisite and necessary to be done in connection with the foregoing as fully as he might or could do in person, hereby ratifying and confirming all that said attorney-in-fact and agent, or any of them, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities and Exchange Act of 1934, this report has been signed by the following persons in the capacities and on the dates indicated.


Signatures	Capacity	Date
/s/ Paul A. Lang	Paul A. Lang President (Principal Executive Officer)	March 31, 2011

/s/ John T. Drexler	John T. Drexler Vice President (Principal Financial and Accounting Officer)	March 31, 2011

Arch Western Acquisition Corporation	Sole Managing Member	March 31, 2011
By: /s/ John T. Drexler John T. Drexler, Vice President

Exhibit Index


Exhibit		Description
3.1		Certificate of Formation (incorporated herein by reference to Exhibit 3.3 to the Registration Statement on Form S-4 (Reg. No. 333-107569) filed by Arch Western Finance, LLC on August 1, 2003).

3.2		Limited Liability Company Agreement (incorporated herein by reference to Exhibit 3.4 to the Registration Statement on Form S-4 (Reg. No. 333-107569) filed by Arch Western Finance, LLC on August 1, 2003).

4.1		Indenture, dated as of June 25, 2003, by and among Arch Western Finance, LLC, Arch Coal, Inc., Arch Western Resources, LLC, Arch of Wyoming, LLC, Mountain Coal Company, L.L.C., Thunder Basin Coal Company, L.L.C. and The Bank of New York, as trustee (incorporated herein by reference to Exhibit 4.1 to the Registration Statement on Form S-4 (Reg. No. 333-107569) filed by Arch Western Finance, LLC on August 1, 2003).

4.2		First Supplemental Indenture, dated October 22, 2004, by and among Arch Western Finance, LLC, Arch Western Resources, LLC, Arch of Wyoming, LLC, Mountain Coal Company, L.L.C., Thunder Basin Coal Company, L.L.C. and The Bank of New York, as trustee (incorporated herein by reference to Exhibit 4.4 of the Current Report on Form 8-K filed by the registrant on October 23, 2004).

4.3		Form of 6³/4% Senior Notes due 2013 (included in Exhibit 4.1).

4.4		Form of Guarantee of 6³/4% Senior Notes due 2013 (included in Exhibit 4.1).

10.1		Federal Coal Lease dated as of June 24, 1993 between the U.S. Department of the Interior and Southern Utah Fuel Company (incorporated herein by reference to Exhibit 10.17 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.2		Federal Coal Lease between the U.S. Department of the Interior and Utah Fuel Company (incorporated herein by reference to Exhibit 10.18 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.3		Federal Coal Lease dated as of July 19, 1997 between the U.S. Department of the Interior and Canyon Fuel Company, LLC (incorporated herein by reference to Exhibit 10.19 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.4		Federal Coal Lease dated as of January 24, 1996 between the U.S. Department of the Interior and the Thunder Basin Coal Company (incorporated herein by reference to Exhibit 10.20 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.5		Federal Coal Lease Readjustment dated as of November 1, 1967 between the U.S. Department of the Interior and the Thunder Basin Coal Company (incorporated herein by reference to Exhibit 10.21 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.6		Federal Coal Lease effective as of May 1, 1995 between the U.S. Department of the Interior and Mountain Coal Company (incorporated herein by reference to Exhibit 10.22 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.7		Federal Coal Lease dated as of January 1, 1999 between the Department of the Interior and Ark Land Company (incorporated herein by reference to Exhibit 10.23 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 1998).

10.8		Federal Coal Lease dated as of October 1, 1999 between the U.S. Department of the Interior and Canyon Fuel Company, LLC (incorporated herein by reference to Exhibit 10 to Arch Coal’s Quarterly Report on Form 10-Q for the quarter ended September 30, 1999).

10.9		Federal Coal Lease effective as of March 1, 2005 by and between the United States of America and Ark Land LT, Inc. covering the tract of land known as “Little Thunder” in Campbell County, Wyoming (incorporated by reference to Exhibit 99.1 to the Current Report on Form 8-K filed by Arch Coal on February 10, 2005).

10.10		Modified Coal Lease (WYW71692) executed January 1, 2003 by and between the United States of America, through the Bureau of Land Management, as lessor, and Triton Coal Company, LLC, as lessee, covering a tract of land known as “North Rochelle” in Campbell County, Wyoming (incorporated by reference to Exhibit 10.24 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2004).

10.11		Coal Lease (WYW127221) executed January 1, 1998 by and between the United States of America, through the Bureau of Land Management, as lessor, and Triton Coal Company, LLC, as lessee,


Exhibit		Description
		covering a tract of land known as “North Roundup” in Campbell County, Wyoming (incorporated by reference to Exhibit 10.24 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2004).

10.12		Master Lease and Sublease Agreement, dated effective as of April 1, 2005, by and between Ark Land Company, Ark Land LT, Inc., Thunder Basin Coal Company, L.L.C. and Triton Coal Company, LLC (incorporated by reference to Exhibit 10.12 to the registrant’s Annual Report on Form 10-K for the year ended December 31, 2005).

10.13		Amendment No. 1 to Master Lease and Sublease Agreement, dated effective as of December 30, 2005, by and between Ark Land Company, Ark Land LT, Inc., Thunder Basin Coal Company, L.L.C. and Triton Coal Company, LLC (incorporated by reference to Exhibit 10.13 to the registrant’s Annual Report on Form 10-K for the year ended December 31, 2005).

10.14		State Coal Lease executed October 1, 2004 by and between The State of Utah, Thru School & Institutional Trust Lands Admin, as lessor, and Ark Land Company and Arch Coal, Inc., as lessees, covering a tract of land located in Seiever County, Utah (incorporated by reference to Exhibit 10.20 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2006).

10.15		State Coal Lease executed September 1, 2000 by and between The State of Utah, Thru School & Institutional Trust Lands Admin, as lessor, and Canyon Fuel Company, LLC, as lessee, for lands located in Carbon County, Utah (incorporated by reference to Exhibit 10.21 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2006).

10.16		Federal Coal Lease executed September 1, 1996 by and between the Bureau of Land Management, as lessor, and Canyon Fuel Company, LLC, as lessee, covering a tract of land known as “The North Lease” in Carbon County, Utah (incorporated by reference to Exhibit 10.22 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2006).

10.17		State Coal Lease executed January 18, 2008 by and between The State of Utah, Thru School & Institutional Trust Lands Admin, as lessor, and Ark Land Company, as lessee, for lands located in Emery County, Utah (incorporated by reference to Exhibit 10.21 to Arch Coal’s Annual Report on Form 10-K for the year ended December 31, 2008).

10.18		Purchase and Sale Agreement, dated as of February 3, 2006, by and among various entities listed on Schedule I, as the originators, and Arch Coal, Inc. (incorporated by reference to Exhibit 10.17 to the registrant’s Annual Report on Form 10-K for the year ended December 31, 2006).

10.19		First Amendment to Purchase and Sale Agreement, dated February 24, 2010, by and among various entities party thereto, as originators, and Arch Coal, Inc. (incorporated by reference to Exhibit 10.1 to the registrant’s Quarterly Report on Form 10-Q for the period ended March 31, 2010).

21.1		Subsidiaries of the registrant.
24.1		Power of attorney (included on signature page hereto).
31.1		Rule 13a-14(a)/15d-14(a) Certification of Paul A. Lang.
31.2		Rule 13a-14(a)/15d-14(a) Certification of John T. Drexler.
32.1		Section 1350 Certification of Paul A. Lang.
32.2		Section 1350 Certification of John T. Drexler.

ARCH WESTERN RESOURCES LLC 10-K