exv99w1

Exhibit 99.1

Merrill Lynch Global Metals, Mining & Steel Conference

Steve Leer, Chairman and CEO Arch Coal, Inc.

Key Biscayne, FL May 14, 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 uncertainties 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 FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Developing nations will increase energy use, putting pressure on global supply

Source: United Nations’ Human Development Report 2007, 2006 World Development Indicators (World Bank)

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Coal’s advantage: abundant, secure and widely dispersed

Based on current production levels and proven reserves, coal should outlast both gas supplies and oil reserves by roughly 4 times

Source: ACI, Bank of America, BP Statistical Review 2007 and Blackwell Energy Research

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Largest U.S. coal plant build-out since 1980 is ongoing, but not enough to satisfy America’s energy needs

· Build-out of 16 GW equates to 54 million tons of new annual coal demand over next five years

– Arch’s reserve base positioned to service two-thirds of these plants

· Roughly 9 GW – another 33 million tons – in advanced permitting stages

· Other fuels used for electric generation are challenged to grow or represent niche players

· Reality is that we need all fuels –along with conservation and efficiency – to meet our growing energy needs

Source: Platts and ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Reserve margins for the U.S. power grid will fall below target levels without adequate investment

Year when reserve margin is expected to fall below target level, by region

America has long had one of the world’s most reliable power systems. Without investment, that could soon change.

Source: NERC 2007 Long-Term Reliability Assessment

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Coal is – and will remain – a vital part of America’s energy future

Source: EIA, Platts, Argus Coal Daily and NYMEX

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Over the long term, clean-coal technologies can broaden market demand for coal

A plug-in hybrid is one Coal can be converted Gasification can reduce

entry for coal into the into transportation fuel emissions and transform

transportation market coal into pipeline-quality

• At current oil prices,

natural gas

• Likely to create coal-to-liquids

significant off-peak facilities are • IGCC and CCS should

demand for electricity economically feasible enable coal to prosper

in a carbon-

constrained world

Public policy initiatives aimed at domestic energy security are spurring debate on energy legislation and incentives for clean-coal technology development

Source: ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Since 1970, coal has been used in increasingly clean ways in the United States

· More progress is expected under existing regulations

· Higher efficiency rates and carbon capture technologies create opportunities for reducing carbon intensity as well

Source: NMA, EPA NOx (Nitrogen Oxide), SO2 (Sulfur Dioxide), PM10 (Particulate Matter)

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Developed nations must adopt climate solutions and export them to developing nations

China surpassed the U.S. in GHG emissions in 2007

The growth rate of GHG emissions in developing nations is likely to significantly exceed that of developed nations

Developed nations must invest in more clean coal technology research & development

Source: IEA World Energy Outlook 2006, Guardian

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Explosive growth in international coal markets underscores the shortage of energy around the globe

Americas Europe/Africa Asia/Pacific Americas expected to Europe/Africa should Asia’s net exports almost double net increase its net projected to decline coal exports in 2008 imports in 2008 significantly in 2008

– Driven by increase in – Significant export – Driven by strong

exports from USA declines from economic growth in

South Africa developing nations

Americas imports

expected to decline – Large switch from – Severe supply

from 2007 levels domestic to imported constraints in

coal in Europe traditional coal

– Driven by lower export nations

– Coal production

import levels into USA

declines in Europe

Global coal supply and demand flows suggest that the world is short of coal by 25 million to 35 million metric tons in 2008, with continued significant supply deficits in 2009 and beyond

Source: ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

In the United States, Arch expects growth in coal demand to accelerate over the next three years

(in million tons) 2008 2009 2010

Growth at Existing Coal Plants +11 +11 +11 New Coal Plant Demand ^1/ 4 22 19 Increase in Gross Exports 20 10 10 Decline in Imports 8 1 - Incremental Demand Growth +43 +44 +40 Cumulative +87 +127

^1/ Net of coal plant retirements.

U.S. coal demand to grow by more than 3% annually through 2010

– U.S. coal generation fleet has increased average utilization by 1 percent annually over the past 10 years

– New coal plant build-out will expand coal consumption meaningfully

– U.S. is expected to become a more significant net exporter given shortage of coal supply worldwide and available port capacity

Source: ACI and Platts

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

While U.S. generator stockpile levels are comfortable, inventories are declining in the East

• Eastern stockpile levels • Western stockpile levels • Total generator stockpile

have declined 7.6 million have increased 5.2 levels have declined 2.4

tons year-to-date million tons year-to-date million tons year-to-date

• In Central Appalachia, • Expect levels to decline • Typically, stockpiles

stocks could fall to near- as demand in the East for build from January

critical levels by autumn replacement tons grows through March

Source: ACI and Energy Ventures Analysis, Inc.

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

PRB coal has gained market share in border states just east of the Mississippi River

Border States East of MS Border States East of MS Border States East of MS

Burn by Coal Type circa 1990 Burn by Coal Type circa 1995 Burn by Coal Type circa 2007

• Eastern border state • By 1995, power plants • Current 69 percent

power plants in Wisconsin, in these four states mix of PRB coal has

Illinois, Tennessee and increased their mix of been achieved with

Mississippi historically PRB coal from 22 relatively modest

burned a small mix of percent to 42 percent capital investment

PRB coal in just five years

Source: ACI and Energy Velocity *Border states represent WS, IL, TN and MS

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

We foresee increased PRB market expansion

opportunities further east of the Mississippi River

· Eastern power plants in non-border states are generally comparable to plants in the border states of WS, IL, TN and MS

· These non-border state plants could theoretically increase their mix of PRB coal as plants in the border states have done

· If plants in non-border states were to switch to PRB coal, the equivalent PRB volume opportunity would represent a potential of 300 million tons

Source: ACI and Energy Velocity

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch Coal is positioned for the future

· One of the largest coal producers in the U.S.

· Core business is providing U.S. power generators with cleaner-burning, low-sulfur coal for electric generation

– Supplies roughly 12% of U.S. coal needs

– Provides source fuel for roughly 6% of U.S. electricity

· Talented workforce operates large, modern mines

· Industry leader in mine safety, productivity and reclamation

Source: ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch’s national scope of operations and reserve base includes presence in four major U.S. coal basins

Powder River Basin
1. Coal Creek 2. Black Thunder

Western Bituminous
1. Skyline 2. Dugout 3. Sufco 4. West Elk

Illinois Basin
Knight Hawk

Central Appalachia

1. Mountain Laurel 2. Coal-Mac 3. Cumberland River 4. Lone Mountain

Source: ACI at 12/31/07

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch is continuing to enhance reputation as a responsible energy company

· Operating the world’s safest coal mines

– Awarded MSHA’s Sentinels of Safety honor for operating the nation’s safest underground coal mines in 2006 and 2007

– Ranked first among coal industry peers for safety performance last year

· Acting as responsible citizens and good environmental stewards

– Inaugural 2007 social responsibility report elevates awareness of Arch’s environmental programs

– Earned 3 National Good Neighbor Awards in 4 years

· Achieving superior financial performance

– Forbes recognized Arch as one of the 100 most trustworthy U.S. companies of 2008

– Expect 2008 to be a record earnings year for Arch

Source: ACI, Forbes

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch has one of the industry’s strongest and cleanest balance sheets

Source: SEC filings compiled by ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch’s mines are strategically positioned to respond to dynamic trends in coal markets

Central Appalachia Western Bituminous Powder River Basin

· Customers span five

· Export growth and

· Supply constraints in

continents supply pressures in other regions and

eastern U.S. are sufficient PRB rail

· Expect to ship 4.5

boosting demand capacity should pull

million tons into global

coal east

and domestic met

· Arch benefits as

markets in 2008; largest producer

· Arch will benefit from

5-6 million in 2009 rising domestic prices

· Have signed

· Pursuing incremental significant export

· In discussions to

margin opportunities business export PRB coal

Source: ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch is advancing clean-coal technology development via a proposed coal-to-liquids plant in Wyoming

· World oil consumption needs are growing, and increasingly will be supplied by OPEC

· CTL can have a positive impact on the U.S. economy, security and environment

· Arch owns an equity interest in DKRW Advanced Fuels

· Proposed plant would capture CO2

to enhance recovery in domestic oil fields

Source: EIA and ACI

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch’s selective approach to signing new contracts retains future upside potential

Source: ACI, Argus Coal Daily 5/9/08

LONG-TERM MACRO FUNDAMENTALS CLIMATE CONCERNS AND CLEAN-COAL TECHNOLOGIES CURRENT TRENDS ABOUT ARCH COAL

Arch continuously evaluates all avenues for value creation

Shareholder Returns

Organic Growth

Invest in core businesses to enhance profit growth and return on capital, evaluate opportunities to further upgrade and expand reserve base

Market Expansion

Consider investments to expand market for coal (and improve coal’s value proposition) through Btu-conversion and other advanced coal technologies

Strategic Growth

Consider acquisitions or other investments that strategically fit and create value

Capital Structure Enhancement

Maintain strong balance sheet, and consider other vehicles for value creation, such as share repurchases or dividend increases, when advantageous

Source: ACI

Merrill Lynch Global Metals, Mining & Steel Conference

Steve Leer, Chairman and CEO Arch Coal, Inc.
Key Biscayne, FL May 14, 2008