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): March 31, 2004
                                                            (March 30, 2004)

                                 Arch Coal, Inc.
             (Exact name of registrant as specified in its charter)

     Delaware                    1-13105                    43-0921172
(State or other jurisdiction (Commission File Number)   (I.R.S. Employer
    of incorporation)                                    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) 994-2700

                               Page 1 of 4 pages.
                         Exhibit Index begins on page 4.

Item 5. Other  Events.

     On March 30, 2004,  Arch Coal,  Inc. (the  "Company"),  responded via press
release to the FTC's  announcement of its intent to block the Company's proposed
acquisition of Triton Coal Company.

Item 7.  Exhibits.

         (c) The following Exhibit is filed with this Current Report on Form

            Exhibit No.               Description
              99                      Press Release dated as of March 30, 2004

                               Page 2 of 4 pages.
                         Exhibit Index begins on page 4.


     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:  March 31, 2004                      ARCH COAL, INC.

                                            By: /s/ Janet L. Horgan
                                                Janet L. Horgan
                                                Assistant General Counsel and
                                                   Assistant Secretary

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                         Exhibit Index begins on page 4.

                                  EXHIBIT INDEX

Exhibit No.                 Description
99                         Press Release dated as of March 30, 2004

                                    Page 4 of 4 pages.

                                                                     Exhibit 99
News from
Arch Coal, Inc.
                                                        FOR FURTHER INFORMATION:
                                           Investors:  Deck Slone (314) 994-2717
                                                 Media:  Kim Link (314) 994-2936

                                                           FOR IMMEDIATE RELEASE
                                                                  March 30, 2004

                  Arch Coal Responds to FTC's Intent to Block
                               Triton Acquisition

     ST. LOUIS - Arch Coal, Inc. (NYSE: ACI) today was informed that the Federal
Trade  Commission  (FTC) will file a lawsuit in federal  district court to block
the company's proposed acquisition of Triton Coal Company.

     "We  respectfully  disagree  with the FTC's  decision to seek a preliminary
injunction challenging the deal," said Steven F. Leer, Arch Coal's president and
chief  executive  officer.  "We  continue to believe  that this  acquisition  is
pro-competitive and would create tremendous  efficiencies that would benefit our
customers and ultimately consumers of electricity."

     The lengthy FTC  investigation  commenced  last year  following Arch Coal's
announcement on May 29, 2003 that the company had signed a definitive  agreement
to acquire Vulcan Coal Holdings LLC, which owns all of the equity of Triton Coal
Company, for a purchase price of $364 million.  Subsequently,  Arch entered into
an  agreement on January 30, 2004,  to sell the Buckskin  Mine to Kiewit  Mining
Acquisition  Company for $82.0  million  contingent on the closing of the Vulcan
transaction.  Buckskin  accounts  for more than 40  percent  of  Triton's  total
production,  and this  transaction  allows for five major producers to remain in
the Sourthern Powder River Basin (SPRB). The commission's  decision to challenge
Arch's  acquisition of Triton's North Rochelle mine took into  consideration the
pending sale of Buckskin to Kiewit.

     "We believe that the FTC  incorrectly  excluded  from its analysis the fact
that competition in the coal business is intense and that the transaction  would
enable Arch itself to become  more  competitive  and  responsive  to  customers'
needs," Leer said. "We look forward to presenting the facts in court."

     In effect, Arch is seeking to acquire a single mine - North Rochelle - that
shares 5.5 miles of property  lines with its existing  Black Thunder  operation,
according to Leer. "We anticipate  that the integration of these two mines would
create  tremendous  opportunities  for cost  savings and  synergies  that should
benefit the customers of both operations," Leer said.

     "In the  meantime,  Arch  continues  to focus on  meeting  the needs of our
electric  utility  customers,"  he added.  "Given the company's  cash balance of
approximately  $325 million and its very  manageable debt level, we believe Arch
has the financial  wherewithal to grow via  acquisitions,  reserve additions and
the continued development of its large and strategic reserve base."

     St.  Louis-based  Arch Coal,  Inc.  is the  nation's  second  largest  coal
producer  and  mines  low-sulfur  coal   exclusively.   Through  its  subsidiary
operations in West Virginia,  Kentucky,  Virginia,  Wyoming,  Colorado and Utah,
Arch provides the fuel for approximately 6 percent of the electricity  generated
in the United States.

                                      # # #

Forward-Looking  Statements:  Statements  in this  press  release  which are not
statements of historical fact are  forward-looking  statements  within the "safe
harbor" provision of the Private Securities Litigation Reform Act of 1995. These
forward-looking  statements are based on information currently available to, and
expectations and assumptions  deemed  reasonable by, the company.  Because these
forward-looking  statements  are  subject  to various  risks and  uncertainties,
actual results may differ  materially  from those  projected in the  statements.
These  expectations,   assumptions  and  uncertainties  include:  the  company's
expectation  that it will be able to consummate  its  acquisition of Vulcan Coal
Holdings;   the  company's  ability  to  realize  the  anticipated  benefits  of
integrating  the North  Rochelle and Black  Thunder  operations if the company's
acquisition  of Vulcan  Coal  Holdings is  consummated;  and the other risks and
uncertainties  which are described  from time to time in the  company's  reports
filed with the Securities and Exchange Commission.