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  <TITLE> Arch Coal, Inc. (Form: 8-K) </TITLE>
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  		UNITED STATES<BR>
  	SECURITIES AND EXCHANGE COMMISSION
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  	WASHINGTON, D.C. 20549
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  	FORM 8-K
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  	CURRENT REPORT
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  	Pursuant to Section&nbsp;13 or 15(d) of the Securities Exchange Act of 1934
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  	Date of Report (Date of Earliest Event Reported):
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  	&nbsp;
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  	December 11, 2006
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  	Arch Coal, Inc.
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  <BR>__________________________________________<BR>
  	(Exact name of registrant as specified in its charter)
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  	Delaware
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  	1-13105
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  	43-0921172
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  _____________________<BR>
  	(State or other jurisdiction
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  _____________<BR>
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  ______________<BR>
  	(I.R.S. Employer
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  	of incorporation)
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  	File Number)
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  	Identification No.)
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  	One CityPlace Drive, Suite 300, St. Louis, Missouri
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  	63141
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  _________________________________<BR>
  	(Address of principal executive offices)
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  	&nbsp;
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  ___________<BR>
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  	Registrant&#146;s telephone number, including area code:
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  	(314) 994-2725
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  	Not Applicable
  <BR>______________________________________________<BR>
  	Former name or former address, if changed since last report
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  	&nbsp;
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  <!-- CoverPageRegistrant END --><P><FONT SIZE="2">
  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:</FONT>
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  <P><FONT SIZE="2">
  [&nbsp;&nbsp;]&nbsp;&nbsp;Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)<br>
  [&nbsp;&nbsp;]&nbsp;&nbsp;Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)<br>
  [&nbsp;&nbsp;]&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))<br>
  [&nbsp;&nbsp;]&nbsp;&nbsp;Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))<br>
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  	Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
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  On December 7, 2006, the Board of Directors of Arch Coal, Inc. (the "Company") elected Paul A. Lang as Senior Vice President &#x2013; Operations.  Mr. Lang has led the Company&#x2019;s western operations as President of Arch Western Resources, LLC since 2005.  Mr. Lang joined the Company in 1984, serving as general manager for the Company&#x2019;s Powder River Basin and southern Wyoming operations from 1998 to 2005.<br><br>Prior to his election, Mr. Lang was already party to an employment agreement with the Company.  The material terms of the employment agreement have been described by the Company in Item 5.02 of its Current Report on Form 8-K filed on November 16, 2006, which description is incorporated herein by this reference.<br>
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  	Item 7.01 Regulation FD Disclosure.
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  On December 11, 2006, the Company issued a press release announcing the election described above.  A copy of the press release is furnished as Exhibit 99.1 hereto and is hereby incorporated by reference.
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  	Item 9.01 Financial Statements and Exhibits.
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  The following exhibit is attached hereto and filed herewith.<br><br>Exhibit No.                         Description<br><br>99.1                      Press release dated December 11, 2006
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  	SIGNATURES
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  	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.
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  	Arch Coal, Inc.
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  	&nbsp;&nbsp;
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  <I>
  	December 11, 2006
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  	By:
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  <I>
  	Robert G. Jones
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  <I>
  	Name: Robert G. Jones
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  <I>
  	Title: Vice President - Law, General Counsel and Secretary
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  	Exhibit&nbsp;Index
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  	Exhibit No.
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  	Description
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  	99.1
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  Press release dated December 11, 2006.
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metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "htm_16920.htm", "description": "LIVE FILING", "secsgml_size_bytes": 11077}]
metadata_filer: {"company-data": {"conformed-name": "ARCH COAL INC", "cik": "0001037676", "assigned-sic": "1221", "irs-number": "430921172", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "001-13105", "film-number": "061267603"}, "business-address": {"street1": "CITY PLACE ONE STE 300", "street2": "ARCH MINERAL CORP", "city": "ST LOUIS", "state": "MO", "zip": "63141", "phone": "3149942700"}, "mail-address": {"street1": "CITYPLACE ONE SUITE 300", "street2": "ARCH MINERAL CORP", "city": "CREVE COEUR", "state": "MO", "zip": "63141"}, "former-company": {"former-conformed-name": "ARCH MINERAL CORP", "date-changed": "19970411"}}
text: Arch Coal, Inc. (Form: 8-K)
  UNITED STATES
  SECURITIES AND EXCHANGE COMMISSION
  WASHINGTON, D.C. 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):
  December 11, 2006
  Arch Coal, Inc.
  __________________________________________
  (Exact name of registrant as specified in its charter)
  Delaware
  1-13105
  43-0921172
  _____________________
  (State or other jurisdiction
  _____________
  (Commission
  ______________
  (I.R.S. Employer
  of incorporation)
  File Number)
  Identification No.)
  One CityPlace Drive, Suite 300, St. Louis, Missouri
  63141
  _________________________________
  (Address of principal executive offices)
  ___________
  (Zip Code)
  Registrant's telephone number, including area code:
  (314) 994-2725
  Not Applicable
  ______________________________________________
  Former name or former address, if changed since last report
  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:
  [  ]  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
  [  ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
  [  ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
  [  ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
  Top of the Form
  Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.
  On December 7, 2006, the Board of Directors of Arch Coal, Inc. (the "Company") elected Paul A. Lang as Senior Vice President – Operations.  Mr. Lang has led the Company's western operations as President of Arch Western Resources, LLC since 2005.  Mr. Lang joined the Company in 1984, serving as general manager for the Company's Powder River Basin and southern Wyoming operations from 1998 to 2005.
  Prior to his election, Mr. Lang was already party to an employment agreement with the Company.  The material terms of the employment agreement have been described by the Company in Item 5.02 of its Current Report on Form 8-K filed on November 16, 2006, which description is incorporated herein by this reference.
  Item 7.01 Regulation FD Disclosure.
  On December 11, 2006, the Company issued a press release announcing the election described above.  A copy of the press release is furnished as Exhibit 99.1 hereto and is hereby incorporated by reference.
  Item 9.01 Financial Statements and Exhibits.
  The following exhibit is attached hereto and filed herewith.
  Exhibit No.                         Description
  99.1                      Press release dated December 11, 2006
  Top of the Form
  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.
  Arch Coal, Inc.
  December 11, 2006
  By:
  Robert G. Jones
  Name: Robert G. Jones
  Title: Vice President - Law, General Counsel and Secretary
  Top of the Form
  Exhibit Index
  Exhibit No.
  Description
  99.1
  Press release dated December 11, 2006.