Item 1.01 Entry Into a Material Definitive Agreement.
On August 27, 2009, Arch Coal, Inc., a Delaware corporation (the "Company"), entered into an amendment (the "Credit Amendment") to its credit agreement, dated December 22, 2004 (as amended, the "Credit Agreement") with the banks named in the Credit Agreement and PNC Bank, National Association, as administrative agent for the banks party thereto.
The purpose of the Credit Amendment was to extend the maturity of a portion of the commitments under the credit facility from June 23, 2011 to March 31, 2013 and to revise the maximum leverage ratio, as determined in accordance with the Credit Agreement. As a result of the Credit Amendment, commitments under the Credit Agreement will be $860.0 million until June 23, 2011, at which time the commitments will decrease to $762.5 million. As amended, the Credit Agreement provides a method by which new banks may join the credit facility after June 23, 2011, subject to an aggregate maximum amount for all banks of $800.0 million. Under the Credit Amendment, the Company has agreed to pay a utilization fee and an unused fee for those banks who agree to extend the maturity of their commitments.
As of August 27, 2009, the Company had no borrowings outstanding under the Credit Agreement.
Some of the banks under the Credit Agreement and/or their affiliates have or may have had various relationships with the Company and its subsidiaries involving the provision of a variety of financial services, including investment banking, underwriting and commercial banking services, including issuances of letters of credit, for which the financial institutions and/or affiliates receive customary fees, and, in some cases, out-of-pocket expenses.
The Company described the material terms of the Credit Agreement in Item 1.01 of its Current Report on Form 8-K filed on December 28, 2004, in Item 1.01 of its Current Report on Form 8-K filed on June 27, 2006, in Item 1.01 of its Current Report on Form 8-K filed on October 6, 2009 and in Item 1.01 of its Current Report on Form 8-K filed on March 12, 2009, and incorporates those descriptions herein by this reference, appropriately modified as set forth above.
A copy of the Credit Amendment is filed as Exhibit 10.1 to this Form 8-K and is incorporated in this Item 1.01 by reference. The description of the Credit Amendment set forth in this Item 1.01 is not complete and is qualified in its entirety by reference to the full text of the Credit Amendment set forth on Exhibit 10.1, and readers are encouraged to review the Credit Amendment in its entirety.
Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant.

Information concerning the amounts for which the Company has become obligated under the Credit Agreement, as amended by the Credit Amendment, set forth above under Item 1.01 is hereby incorporated by reference into this Item 2.03.

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Item 9.01 Financial Statements and Exhibits.
(d) Exhibits

The following exhibit is attached hereto and filed herewith.

Exhibit
No. Description

10.1 Fourth Amendment to Credit Agreement, dated as of August 27, 2009, by and among Arch Coal, Inc., the banks party thereto, Citicorp USA, Inc., JPMorgan Chase Bank, N.A. and Wachovia Bank, National Association, each in its capacity as syndication agent, Bank of America, N.A. (as successor-by-merger to Fleet National Bank), as documentation agent, and PNC Bank, National Association, as administrative agent for the banks.

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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: August 28, 2009 Arch Coal, Inc.

By: /s/ Robert G. Jones

Robert G. Jones Senior Vice President-Law, General Counsel and Secretary

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