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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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<SEC-DOCUMENT>0001209191-06-010408.txt : 20060214
<SEC-HEADER>0001209191-06-010408.hdr.sgml : 20060214
<ACCEPTANCE-DATETIME>20060214162104
ACCESSION NUMBER:		0001209191-06-010408
CONFORMED SUBMISSION TYPE:	5
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051231
FILED AS OF DATE:		20060214
DATE AS OF CHANGE:		20060214

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			MESSEY ROBERT J
		CENTRAL INDEX KEY:			0001129715

	FILING VALUES:
		FORM TYPE:		5
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13105
		FILM NUMBER:		06615524

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		3149942930

	MAIL ADDRESS:	
		STREET 1:		13318 WOOD STONE COURT
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63141

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARCH COAL INC
		CENTRAL INDEX KEY:			0001037676
		STANDARD INDUSTRIAL CLASSIFICATION:	BITUMINOUS COAL & LIGNITE SURFACE MINING [1221]
		IRS NUMBER:				430921172
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		CITY PLACE ONE STE 300
		STREET 2:		ARCH MINERAL CORP
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63141
		BUSINESS PHONE:		3149942700

	MAIL ADDRESS:	
		STREET 1:		CITYPLACE ONE SUITE 300
		STREET 2:		ARCH MINERAL CORP
		CITY:			CREVE COEUR
		STATE:			MO
		ZIP:			63141

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ARCH MINERAL CORP
		DATE OF NAME CHANGE:	19970411
</SEC-HEADER>
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<TYPE>5
<SEQUENCE>1
<FILENAME>doc5.xml
<DESCRIPTION>FORM 5 SUBMISSION
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    <schemaVersion>X0202</schemaVersion>

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        <issuerName>ARCH COAL INC</issuerName>
        <issuerTradingSymbol>ACI</issuerTradingSymbol>
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            <rptOwnerName>MESSEY ROBERT J</rptOwnerName>
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            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>ST. LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63141</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior Vice President &amp; CFO</officerTitle>
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                <transactionPricePerShare>
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    <footnotes>
        <footnote id="F1">Each share of phantom stock represents a right to receive the value in cash of one share of Arch Coal, Inc. common stock. The shares of phantom stock are held by the executive officer through the Arch Coal, Inc. Deferred Compensation Plan (the &quot;Plan&quot;) and represent past compensation, the vested portion of restricted stock awards and/or payouts under other incentive compensation arrangements that the executive officer elected to defer under the Plan into a hypothetical investment in shares of Arch Coal, Inc. common stock and/or dividends paid with respect to such deferred amounts.</footnote>
        <footnote id="F2">Shares of phantom stock are payable in cash on the date or dates elected by the executive officer, subject to the terms of the Plan.  The executive officer may transfer any or all of the phantom stock account into an alternative investment account at any time.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Gregory A. Billhartz, Attorney-in-Fact</signatureName>
        <signatureDate>2006-02-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----