Item 7.01 Regulation FD Disclosure.

On July 27, 2009, Arch Coal, Inc. issued a press release announcing the pricing of its public offering of common stock. The press release is attached hereto as Exhibit 99.1 and incorporated herein by reference. Item 9.01 Financial Statements and Exhibits.

(d) Exhibits The following exhibit is attached hereto and filed herewith.

Exhibit
No. Description

99.1 Press release dated July 27, 2009.

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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: July 27, 2009 Arch Coal, Inc.

By: /s/ Robert G. Jones Robert G. Jones Senior Vice President - Law, General Counsel and Secretary

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