8-K

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT
Pursuant to Section 13 or 15(d)
of the Securities Exchange Act of 1934

Date of report (Date of earliest event reported): September 4, 2008 (September 4, 2008)

Arch Coal, Inc.

(Exact name of registrant as specified in its charter)

Delaware
(State or other jurisdiction of
incorporation) 1-13105
(Commission File Number) 43-0921172
(I.R.S. Employer Identification No.)

CityPlace One
One CityPlace Drive, Suite 300
St. Louis, Missouri 63141
(Address, including zip code, of principal executive offices)

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

     Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

o   Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o   Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o   Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o   Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01 Regulation FD Disclosure.

          On September 4, 2008, Steven F. Leer, Chairman and Chief Executive Officer of Arch Coal, Inc., will deliver a presentation at the Lehman Brothers CEO Energy/Power Conference that will include written communication comprised of slides. The slides from the presentation are attached hereto as Exhibit 99.1 and are hereby incorporated by reference.

          A copy of the slides will be available at http://investor.archcoal.com/events.cfm for 30 days.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

          The following exhibit is attached hereto and furnished herewith.

Exhibit
No.	Description
99.1	Slides from the presentation at the Lehman Brothers CEO Energy/Power Conference.

1

Signatures

          Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: September 4, 2008	Arch Coal, Inc.
	By:	/s/ Robert G. Jones
		Robert G. Jones
		Vice President — Law, General Counsel and Secretary

2

Exhibit Index

Exhibit
No.	Description
99.1	Slides from the presentation at the Lehman Brothers CEO Energy/Power Conference.

EX-99.1

Exhibit 99.1

Lehman Brothers CEO Energy/Power Conference Steve Leer, Chairman and CEO Arch Coal, Inc. New York City September 4, 2008

Forward-Looking Information This presentation contains forward-looking statements that is, statements related to future, not past, events. In this context, forward-looking statements often address our expected future business and financial performance, and often contain words such as expects, anticipates,intends,plans,believes,seeks,or will.Forward-looking statements by their nature address matters that are, to different degrees, uncertain. For us, particular uncertainties arise from changes in the demand for our coal by the domestic electric generation industry; from legislation and regulations relating to the Clean Air Act and other environmental initiatives; from operational, geological, permit, labor and weather-related factors; from fluctuations in the amount of cash we generate from operations; from future integration of acquired businesses; and from numerous other matters of national, regional and global scale, including those of a political, economic, business, competitive or regulatory nature. These uncertaintie s 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. For a description of some of the risks and uncertainties that may affect our future results, you should see the risk factors described from time to time in the reports we file with the Securities and Exchange Commission.

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 30%20%40%60%80%100%$0$10,000$20,000$30,000$40,000U.S.AustraliaU.K.ItalyS. KoreaRussiaMexicoChinaIndiaAsias industrial revolution is testing global energy supply infrastructureElectricity Usage per CapitaGDP per capita (in U.S. $)Urbanization rate of population-3,0006,0009,00012,00015,000$0$10,000$20,000$30,000$40,000U.S.AustraliaU.K.ItalyS. KoreaRussiaMexicoChinaIndiaPopulation UrbanizationGDP per capita (in U.S. $)Kilowatt-hours per capitaNote: bubble size reflects size of populationSource: United NationsHuman Development Report 2007, 2006 World Development Indicators (World Bank)

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Chinas vehicle fleet is projected to surpass that of the United States post 2030 0100200300400500600200020102020203020402050Source: Department of Energy / Argonne National LaboratoryNumber of Highway Vehicles in China(in million units)U.S.: 251 mmU.S.:330 mmChinese vehicle fleetprojected to grow by 217 million vehicles between 2010 and 2030China is projected to add another 309 million vehicles from 2030 to 2050, surpassing the U.S.Significant strainon energy transport infrastructure

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALAround the globe, countries are embracing coal as a primary source for electricity Europe(non-CIS)33 GW online by 20152007 GlobalCoal Production:6 billion metric tons CIS countries 9 GW online by 2015 China 216 GW online by 2013 Other Asia 26 GW online by 2015 India67 GW online by 2013 Central &South America 6 GW online by 2013Central &South America 6 GW online by 2013 United States 24 GW online by 2014 Slide 5The demand for coal will increase sharply as coal-fired plant constructionsare being carried out at a break neck pace. By 2012, the world would need an estimated additional 1.1 billion short tons of new coal supply.-Friedman, Billings Ramsey (6/08)Source: ACI and Platts International

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Growing worldwide steel production and blast furnace capacity additions are stoking met coal demand Slide 62007200820092010243.3Projected Import Metallurgical Coal Demand(in million metric tons)Source: McCloskey Metallurgical Coal Third Quarter 2008 Report, International Iron & Steel Institute, AME Mineral Economics PricingAsiaRest of WorldSouth America253.1267.2282.5Global importmet coaldemand expected to grow by ~40 million tons over next 3 yearsMore than 75 percent of the expected growth is being driven by increased consumption in Asia and South AmericaMet coal pricing has risen sharply since 200 3; expect continued market tightnessArch is poised to capitalizeon strong met and PCI coal trends with its Mountain Laurel, Pardee and Lone Mountain mines$0$50$100$150$200$250$30002/0303/0404/0505/0606/0707/0808/09Benchmark Pricing for Met Coal($/metric ton, FOB the port basis)Premium hard coking coalSemi-soft & hi-vol PCI

Slide 7LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALGlobal coal supply flows are shifting due to growing demand and severe supply constraintsKey Trends in Asia-Pacific Coal MarketsKey Trends in Atlantic Basin Coal MarketsSource: ACIAustralia: severe port and rail bottlenecks may mask underlying labor and mine challenges; expanded capacity still may undershoot growing Asian demandIndonesia: increasing domestic demand; export capacity depend ent on congested river systemChina: substantial growth in domestic demand will likely push country to a net importer status as early as 2008Vietnam: growing domestic demand expected to reduce export supplyIndia: imported coal needs projected to rise meaningfully; will pull available supply from Atlantic Basin marketsSouth America: port infrastructure constraints; political instability; resource nationalism; growing regional coal burnUSA: swing supplier to Atlantic basin market; available coal export ca pacity; imports into country decliningEurope: coal production declining; growing coal burn in eastern Europe; traditional import supply avenues waningRussia: production challenges; growing domestic coal consumption; exports increasingly shifting to Asia-Pacific marketSouth Africa: domestic power shortage; reserve degradation; exports increasingly shifting to Asia-Pacific market

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 8OilNatural GasCoal0100200billions of tons of oil equivalentCoals advantage: abundant, secure and widely dispersedSource: ACI, Bank of America, BP Statistical Review 2007 and Blackwell Energy ResearchBased on current production levels and proven reserves, coal should outlast both gas supplies and oil reserves by roughly 4 timesNorth AmericaCentral and South AmericaEuropeMiddle EastAfricaRussiaIndiaChinaOther Asia Pacific

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL (in million tons)200820092010Growth at Existing Coal Plants-+10+10New Coal Plant Demand 1/42220Increase in Gross Exports241010Decline in Imports2--Incremental Demand Growth+30+42+40Cumulative+72+1121/ Net of coal plant retirements.U.S. coal demand to grow by more than 100 million tonsby 2010Average utilization increasesof ~1% annually over the past 10 years (2008 projected to be weaker economically)New coal plant build-outwill expand coal consumption meaningfullyU.S. is expected to become a more signifi cant net exportergiven shortage of coal supply worldwide and available port capacitySource: ACI and PlattsIn U.S. coal markets, Arch expects above-average demand growth over the next three years

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 10Source: Platts and ACIBuild-out of 17.5 GW equates to 62 million tonsof new annual coal demand over next four yearsPowder River Basinlikely will service at least halfof these plantsMore than 7 GW another 20 million tons in advanced permitting stagesAnticipated Supply Region for Coal Plants Under Construction(in millions of tons)PRBNon-PRBLargest coal plant build-out since 1980 will meaningfully expand coal demand0816242008200920102011+

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALAvailable U.S. port capacity and strong international demand will expand coal exports Available eastern export port capacity at Baltimore and Hampton RoadsExisting port capacity at southern ports of Mobile, New Orleans, Charleston and TexasLimited port capacity on West Coast Annual U.S. Gross Exports(in millions of short tons)0255075100125919293949596979899000102030405060708E+40% Source: ACI and NMASlide 11

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 12U.S. coal supply growth is not keeping pace with projected U.S. coal demand in 2008Increase in 1H08 U.S. Coal Production(versus 1H07, in million tons, per MSHA)Source: MSHA, EIA and ACIOtherSAPPCAPPILBWBITSPRBNPRBFCNAPP-4048First half 2008 total U.S. coal production increased just 1.2 million tonsvs. first half of 2007Some Appalachian steam coal is crossing overto met markets, further reducing available steam coal supplySouthern PRBNorthern PRBWestern BitFour CornersIllinois Basi nNorthernAppalachiaCentralAppalachiaSouthernAppalachia

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 13Total U.S. coal stockpile levels appear adequate with eastern days-supply levels indicating tightness Western Inventory Levels(in days of burn)Eastern Inventory Levels(in days of burn)53434860We have blended in an increasing amount of Powder River Basin coal, and we while rebalancing the portfolio have remained within our dispatch price targets by blending in cheaper coals. -AEP (5/08)There is genuinely a tightnessin the marketdriven by international fundamentals, global demands.-AEP (5/08)We d id have the risk of shortagesa year and a half ago our piles got pretty dramatically low Coal conservationin our instance affected our ability to sell some [power] into the wholesale market. With this, it showed that we need to have more inventory and we need to keep that stockpile. So, we certainly have increased our [targets] -Great Plains Energy (5/08)Source: ACI, Energy Ventures Analysis and Select Generator TranscriptsJuly'07July'08July'07July'08

Slide 14LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALSource: ACI and Energy VelocityIn past cycles, PRB coal has gained market share in border states just east of the Mississippi RiverBorder States East of Mississippi RiverBurn by Coal Type circa 1990PRBNon-PRB78%22%Eastern border statepower plants in Wisconsin, Illinois, Tennessee and Mississippi historically burned a small mix of PRB coal18%32%50%Border States East of Mississippi River Burn by Coal Type circa 1995PRBNon-PRB58%42%Border States East of Mississippi RiverBurn by Coal Type circa 2007PRBNon-PRB31%69%By 1995, power plants in these four states increased their mix of PRB coalfrom 22 percent to 42 percent in just five yearsCurrent 69 percent mix of PRB coal has been achieved with relatively modest capital investment*Border states represent WS, IL, TN and MS

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 15PRBPRB switching opportunityNon-PRBWe foresee increased PRB market expansion opportunities further east of the Mississippi RiverNon-Border States East of Mississippi RiverBurn by Coal Type circa 200718%31%51%Source: ACI and Energy VelocityEastern power plants in non-border states are generally comparable in designto plants in the border statesNon-border state plants should be able to increase their PRB coal usegreatly with minimal investmentBased on historical switching in the border states and the lower heat content of PRB coal, the theoretical PRB switching opportunityin the East exceeds 300 million tonsSuch development is underway. In recent weeks, Arch has signed agreementswith non-traditional PRB customers to test as well as increase burn of PRB coal.

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Since 1970, coal has been used in increasingly clean ways in the United States Slide 16-100%-50%0%50%100%150%200%197019751980198519901995200020052006Higher efficiency rates and carbon capture technologiescreate opportunities for reducing carbon intensity as wellElectricity fromcoal +182%NOx-33%SO2-55%PM10-83%Source: NMA, EPA NOx (Nitrogen Oxide), SO2 (Sulfur Dioxide), PM10 (Particulate Matter)GDP +203%US population+46%

Slide 17LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALSource: ACI, Google and Congressional web sitesThere is support for coals essential role in Americas energy future well need to invest more in the clean technology that will allow us to burn more coal, our countrys most abundant fossil fuel. well need to invest more in the clean technology that will allow us to burn more coal, our coun trys most abundant fossil fuel.Senator Barack Obama (D-IL) We are sitting on the worlds largest supply of energy in our coal reserves and that has to be one of the fundamental components of energy independence.SenatorJohn McCain (R-AZ)

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 18United StatesChinaRest of Non-OECDRest of OECDDeveloped nations must adopt climate solutions and export them to developing nationsCO2Emission Trends(1990 -2030)Source: IEA World Energy Outlook 2006, Guardian199015Gt of CO212963019952000200520102015202020252030China surpassed the U.S. in GHG emissionsin 2007The growth rate of GHG emissions in developing nationsis likely to significantly exceed that of developed nationsDeveloped nations must invest in more clean coaltechnology research & development

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Arch Coal is well-positioned for the futureOne of the largestcoal producers in the United StatesWe supply roughly 12 percentof the U.S. coal supplyProvide cleaner-burning, low-sulfur coal to fuel 6 percent of the nations electricityShip coal to domestic and international steel manufacturers as well as international power producers Our talented workforceoperates large, modern and efficient mines Industry leaderin mine safety, productivity and reclamation Source: ACISlide 19

Slide 20LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALSource: ACI at 12/31/0712123421342.9-Billion Ton Reserve BaseComplianceLow-sulfurHigh-sulfurArchs national scope of operations and reserve base includes presence in four major U.S. coal basinsWestern Bituminous1. Skyline2. Dugout3. Sufco4. West ElkPowder River Basin1. Coal Creek2. Black ThunderIllinois BasinKnight HawkCentral Appalachia1.Mountain Laurel2.Coal-Mac3.Cumberland River4.Lone M ountainPRB(1,753)WBIT(460)ILB(376)CAPP(338)

Slide 21LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COALArchs mine portfolio underscores value of diversitySource: ACIPRB: 76%WBIT: 15%CAPP: 9%2007 ACI Coal Production(percent of total tons by region)PRB47%WBIT22%CAPP31%2007 ACI Revenue(percent of total revenue by region)PRB41%WBIT33%CAPP26%2007 ACI Income(percent of segment income by region)

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 22Peer 1Peer 2Peer 3Peer 4ACILegacy Liabilities of Largest U.S. Coal Companies(12/31/07, in millions)Net Debt as a Percentage of Capitalization(at 12/31)$3,431$1,302$759$389$336Arch has one of the industrys strongest and cleanest balance sheetsSource: SEC filings compiled by ACIWorkersCompPost-Retirement MedicalReclamationPension83.9%58.0%38.9%46.2%46.0%20002002200420062007

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 23Arch is continuing to enhance its reputation as a responsible energy company Source: ACI, ForbesOperating the worlds safestcoal minesAwarded MSHAs Sentinels of Safety honor for operating the nations safest underground coal mines in 2006 and 2007Ranked first among coal industry peers for safety performance last yearActing as responsible citizens and good environmental stewardsInaugural 2007 social responsibility report elevates awareness of Archs environmental programsEarned 3 National Good Neighbor Awards in 4 yearsAchieving superior financial performanceForbesrecognized Arch as one of the 100 most trustworthy U.S. companies of 2008Expect 2008 to be a record earnings year for Arch

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Slide 24200820092010Archs selective approach to signing new contracts retains future upside potentialArch Unpriced Volume(in millions of tons at 6/30/08)4-865-7585-95Steam coalMetallurgical coalPRB 8,800WBIT 11,700CAPP12,500Steam Coal Price Comparison ($/short ton, as of 8/29/08)$72.00$127.00Source: ACI, Argus Coal Dailys Physical Market Assessment$17.50Arch 2Q08 realized price by regionIndex coal pricefor 2009 deliveryACI2Q08PRBWBITCAPP$29.91$69.54$11.38ACI2Q08ACI2Q08

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL DomesticOPECNon-OPECArch owns an equity interestin DKRW Advanced FuelsPlan to build a 19,000 bpd coal-to-gasoline facilityin southern WyomingPlant would capture CO2emissions to enhance recovery in domestic oil fieldsOver the long-term, Archs coal-to-liquids vision can help America address energy security concernsCoalNatural GasOilCoal: 94%U.S. Petroleum Supply(million barrels per day)U.S. Energy Reserves(in trillion Btu)OtherImports 30%PRB8800NaturalGasCrudeOilU.S. Fuel Prices($/million Btu at 9/2/08, Q109 delivery)$19=$110perbbl $1$8Domestic: 35%OPEC 35% Source: EIA, Platts and NYMEX

LONG-TERM MACRO ENERGY FUNDAMENTALSU.S. COAL INDUSTRY DYNAMICSCLIMATE AND CLEAN-COAL TECHNOLOGIESABOUT ARCH COAL Archs future growth avenues are compelling Invest in core businesses to enhance profit growth and return on capital, evaluate opportunities to further upgrade and expand reserve baseConsider acquisitions or other investments that strategically fit and create valueConsider investments to expand market for coal (and improve coals value proposition) through Btu-conversion and other advanced coal technologiesOrganic GrowthStrategic GrowthMarket ExpansionShareholderReturnsMaintain strong balance sheet, and consider other vehicles for value creation, suc h as share repurchases or dividend increases, when advantageousCapital Structure EnhancementSource: ACI