UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 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): May 26, 2006 (May 26, 2006)

Arch Coal, Inc.

(Exact name of registrant as specified in its charter)

Delaware		1-13105		43-0921172
(State or other jurisdiction of		(Commission File Number)		(I.R.S. Employer Identification No.)
incorporation)

CityPlace One
One CityPlace Drive, Suite 300
St. Louis, Missouri 63141

(Address, including zip code, of principal executive offices)

Registrant’s telephone number, including area code: (314) 994-2700

     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))

 

 

Item 8.01 Other Events.

     On May 26, 2006, Arch Coal, Inc. (the “Company”) contributed 350,000 shares of its common stock, including 168,400 treasury shares, to the Arch Coal, Inc. Retirement Account Plan (the “Plan”). Also on May 26, 2006, the Company filed a prospectus supplement with the Securities and Exchange Commission (the “SEC”) pursuant to Rule 424(b) of the Securities Act of 1933, as amended, in order to register the resale of these shares of common stock by the Plan from time to time under the Company’s universal shelf registration statement filed with the SEC in March 2006. Attached as Exhibit 5.1 hereto is an opinion of counsel regarding the legality of the shares of common stock covered by the prospectus supplement.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

     The following exhibit is attached hereto and filed herewith.

		Exhibit
		No.		Description
		5.1		Opinion of counsel.

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.

Exhibit Index

Exhibit
No.		Description
5.1		Opinion of counsel.

Exhibit 5.1

[Arch Coal, Inc. letterhead]

May 26, 2006

Board of Directors
Arch Coal, Inc.
One CityPlace Drive, Suite 300
St. Louis, Missouri 63141

Dear Ladies and Gentlemen:

     I am Assistant General Counsel and Assistant Secretary for Arch Coal, Inc., a Delaware corporation (the “Company”). This opinion letter is being furnished to you in connection with the registration under the Securities Act of 1933, as amended (the “Act”), of the offering by the Arch Coal, Inc. Retirement Account Plan of 350,000 shares of the Company’s common stock, par value $0.01 per share (the “Common Stock”).

     In connection herewith, I have examined:

	(i)		the Registration Statement on Form S-3 (Reg. No. 333-132413) (the “Registration Statement”) covering, among other securities, the Common Stock, which Registration Statement became effective under the Act on March 14, 2006; and
	(ii)		the prospectus supplement dated May 26, 2006 and accompanying prospectus included in the Registration Statement, which were filed with the Securities and Exchange Commission (the “Commission”) on the date hereof, pursuant to Rule 424(b) under the Act (collectively, the “Prospectus”).

     I have also examined originals or copies certified or otherwise identified to my satisfaction of the Restated Certificate of Incorporation of the Company filed with the Secretary of State of Delaware on May 3, 2006, the Restated and Amended Bylaws of the Company and such other corporate records, agreements and instruments of the Company, certificates of public officials and officers of the Company and such other documents, records and instruments, and I have made such legal and factual inquiries as I have deemed necessary or appropriate as a basis to render the opinions hereinafter expressed.

     In my examination of the foregoing, I have assumed the genuineness of all signatures on all documents examined by me (except the signatures of officers of the Company), the legal competence and capacity of each person executing documents, the authenticity of all documents submitted to me as originals, the conformity to authentic originals of all documents submitted to me as certified or photostatted copies, and the due authorization, execution and delivery of all documents (other than due authorization, execution and delivery on behalf of the Company) where due authorization, execution and delivery are a prerequisite to the effectiveness thereof.

     Based upon the foregoing and in reliance thereon, and subject to the exceptions, qualifications and limitations stated herein, I am of the opinion that the Common Stock has been duly authorized and issued and is fully paid and non-assessable.

     The opinions expressed above are limited to the laws of the State of Missouri, the Federal laws of the United States of America and, to the extent required by the foregoing, the General Corporation Law of the State of Delaware as in effect (and published or otherwise generally available) on the date hereof, and I assume no obligation to revise or supplement the opinions should such law be changed by legislative action, judicial decision or otherwise. In rendering the opinions, I have not considered, and hereby disclaim any opinion as to, the application or impact of any laws, cases, decisions, rules or regulations of any other jurisdiction, court or administrative agency.

     I hereby consent to the filing of this opinion as Exhibit 5.1 to the Current Report on Form 8-K and to the use of my name under the caption “Legal Matters” in the Prospectus. In giving such consent, I do not thereby concede that I am within the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission thereunder.