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                                                                    EXHIBIT 10.3

                                FIRST AMENDMENT
                    TO AMENDED AND RESTATED CREDIT AGREEMENT

      THIS FIRST AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (the
"Amendment") dated and effective as of October 22, 2004, is made by and among
ARCH COAL, INC., a Delaware corporation (the "Borrower"), the LENDERS (as
hereinafter defined), JPMORGAN CHASE BANK, in its capacity as syndication agent,
CITIBANK, N.A., CALYON NEW YORK BRANCH (SUCCESSOR BY MERGER TO CREDIT LYONNAIS
NEW YORK BRANCH) and U.S. BANK NATIONAL ASSOCIATION, each in its capacity as a
documentation agent, and PNC BANK, NATIONAL ASSOCIATION, in its capacity as
administrative agent for the Lenders (hereinafter referred to in such capacity
as the "Administrative Agent").

                              W I T N E S S E T H:

      WHEREAS, the Borrower, JPMorgan Chase Bank, as syndication agent,
Citibank, N.A., Calyon New York Branch and U.S. Bank National Association, each
in its capacity as documentation agent, PNC Bank, National Association, as
administrative agent, and certain lenders are parties to that Amended and
Restated Credit Agreement dated as of August 20, 2004 (the "Credit Agreement");
and

      WHEREAS, Arch Western Group (as defined in the Credit Agreement) desires
to issue up to $300,000,000 in principal amount of additional AWR Senior Notes
(as defined in the Credit Agreement) and, in connection therewith, enter into a
supplement to the AWR Senior Notes Indenture (as defined in the Credit
Agreement); and

      WHEREAS, the parties desire to amend the Credit Agreement as hereinafter
provided.

      NOW, THEREFORE, the parties hereto, in consideration of their mutual
covenants and agreements hereinafter set forth and intending to be legally bound
hereby, covenant and agree as follows:

      1. Definitions.

      As used in this Amendment, the following capitalized terms have the
following meanings:

      "AWR Supplement" shall mean the supplement to the AWR Senior Notes
Indenture in connection with the issuance of up to $300,000,000 in principal
amount of additional AWR Senior Notes.

      "Additional AWR Notes" shall mean the issuance of up to $300,000,000 of
AWR Senior Notes pursuant to the AWR Senior Notes Indenture as supplemented by
the AWR Supplement.

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      All other capitalized terms used herein unless otherwise defined herein
shall have the meanings ascribed to them in the Credit Agreement.

      2. Amendment of Credit Agreement.

      (a) Section 1.1 [Certain Definitions] of the Credit Agreement is hereby
amended to insert the following new definition of "AWR Senior Notes Indenture
Supplement" between the definition of "AWR Senior Notes Indenture" and the
definition of "Banks":

            "AWR Senior Notes Indenture Supplement shall mean the supplement to
            the AWR Senior Notes Indenture dated October 22, 2004 in connection
            with the issuance of additional AWR Senior Notes in an aggregate
            amount of up to $300,000,000."

      (b) The definition of AWR Senior Notes Indenture in Section 1.1 [Certain
Definitions] of the Credit Agreement is hereby amended and restated to read as
follows:

            "AWR Senior Notes Indenture shall mean the indenture, governing the
            AWR Senior Notes, as in effect on the Second Amendment Effective
            Date, as supplemented by the AWR Senior Notes Indenture Supplement
            and without regard to any restatement, amendment, modification or
            supplement thereof after the Second Amendment Effective Date (other
            than the AWR Senior Notes Indenture Supplement which is expressly
            permitted)."

      (c) Clause (i) of the definition of "Permitted Additional AWR
Indebtedness" in Section 1.1 [Certain Definitions] of the Credit Agreement is
hereby amended and restated to read as follows:

            "(i) the aggregate principal amount of such Indebtedness at any time
            outstanding shall not exceed $1,000,000,000;"

      3. Conditions of Effectiveness of this Amendment.

      The effectiveness of this Amendment is expressly conditioned upon
satisfaction of each of the following conditions precedent:

      (a) Fees and Expenses. The Borrower shall pay or cause to be paid to the
Administrative Agent for itself the reasonable costs and expenses of the
Administrative Agent including, without limitation, reasonable fees of the
Administrative Agent's counsel in connection with this Amendment.

      (b) No Default. Confirmation of Representations and Warranties, etc. The
Borrower by executing this Amendment hereby certifies and confirms that as of
the date hereof and after giving effect to this Amendment, the issuance of the
Additional AWR Notes and the supplement

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of the AWR Senior Notes Indenture pursuant to the AWR Supplement: (i) the
execution, delivery and performance of this Amendment and any and all other
documents executed and/or delivered in connection herewith have been authorized
by all requisite corporate action on the part of the Borrower and will not
violate the Borrower's articles of incorporation or bylaws, (ii) no Event of
Default or Potential Event of Default has occurred and is continuing or
otherwise exists, (iii) the representations and warranties of the Loan Parties
contained in the Credit Agreement and the other Loan Documents are true and
correct on and as of the date hereof with the same force and effect as though
made by the Loan Parties on such date (except representations and warranties
that relate solely to an earlier date or time), (iv) the Additional AWR Notes
meet all of the requirements of and constitute Permitted Additional AWR
Indebtedness; and (v) the Loan Documents are and remain legal, valid, binding
and enforceable obligations in accordance with the terms thereof.

      (c) AWR Supplement; Other Matters. The AWR Supplement shall be reasonably
acceptable to the Agents based upon the requirements of the definition of
Permitted Additional AWR Indebtedness (as such definition is amended by this
Amendment). The Administrative Agent shall have received an opinion from
Kirkpatrick and Lockhart LLC, legal counsel to the Loan Parties, in form and
substance reasonably satisfactory to the Administrative Agent.

      (d) Confirmation of Loan Documents. Each Loan Party (other than the
Borrower) shall have duly executed and delivered to the Administrative Agent the
Confirmation of Loan Documents in the form attached hereto as Exhibit A.

      (e) Organization, Authorization and Incumbency. There shall be delivered
to the Administrative Agent for the benefit of each Lender a certificate, dated
as of the date hereof and signed by the Secretary or an Assistant Secretary of
each Loan Party, certifying as appropriate as to:

            (i) all action taken by such Loan Party in connection with this
      Amendment and the other Loan Documents;

            (ii) the names of the officer or officers authorized to sign this
      Amendment and the other documents executed and delivered in connection
      herewith and described in this Section 3 and the true signatures of such
      officer or officers and specifying the officers authorized to act on
      behalf of each Loan Party for purposes of the Loan Documents and the true
      signatures of such officers, on which the Agents and each Lender may
      conclusively rely; and

            (iii) copies of its organizational documents, including its
      certificate of incorporation and bylaws if it is a corporation, its
      certificate of partnership and partnership agreement if it is a
      partnership, and its certificate of organization and limited liability
      company operating agreement if it is a limited liability company, in each
      case as in effect on the date hereof, certified by the appropriate state
      official where such documents are filed in a state office together with
      certificates from the appropriate state officials as to the continued
      existence and good standing of each of the Loan Parties in each state
      where organized or qualified to do business; provided that each of the
      Loan

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      Parties other than Borrower may, in lieu of delivering copies of the
      foregoing organizational documents and good standing certificates, certify
      that the organizational documents and good standing certificates
      previously delivered by the Loan Parties to the Administrative Agent
      remain in full force and effect and have not been modified, amended or
      rescinded.

      (f) Consents and Approvals. To the extent any consent, approval, order, or
authorization or registration, declaration, or filing with any governmental
authority or other person or legal entity is required in connection with the
valid execution and delivery of this Amendment or the carrying out or
performance of any of the transactions required or contemplated by this
Amendment, all such consents, approvals, orders or authorizations shall have
been obtained or all such registrations, declarations, or filings shall have
been accomplished prior to the consummation of this Amendment.

      (g) Litigation. On the date hereof no action, proceeding, investigation,
regulation or legislation shall have been instituted, threatened or proposed
before any court, governmental agency or legislative body to enjoin, restrain or
prohibit, or to obtain damages in respect of, this Amendment or any other Loan
Documents or the consummation of the transactions contemplated hereby or thereby
or which, in the Administrative Agent's sole discretion, would make it
inadvisable to consummate the transactions contemplated by this Amendment or any
of the other Loan Documents.

      (h) Legal Details; Counterparts. All legal details and proceedings in
connection with the transactions contemplated by this Amendment shall be in form
and substance satisfactory to the Administrative Agent, the Administrative Agent
shall have received from the Borrower and the Required Banks an executed
original of this Amendment and the Administrative Agent shall have received all
such other counterpart originals or certified or other copies of such documents
and proceedings in connection with such transactions, in form and substance
satisfactory to the Administrative Agent.

      This Amendment shall be dated as of and shall become effective on the date
that (such date being hereinafter referred to as the "Effective Date"): (i) it
has been duly executed by the Borrower, the Administrative Agent and the
Required Banks, and (ii) each of the conditions set forth in this Section 3 has
been satisfied.

      4. Force and Effect.

      No novation is intended or shall occur by or as a result of this
Amendment. Except as the Credit Agreement is expressly amended hereby, the
Credit Agreement and the other Loan Documents remain in full force and effect
and are hereby ratified and confirmed by the Borrower. This Amendment is not
intended to constitute, nor does it constitute, an interruption, suspension of
continuity, satisfaction, discharge of prior duties, novation, or termination of
the liens, security interests, indebtedness, loans, liabilities, expenses, or
obligations under the Credit Agreement or the other Loan Documents. The Borrower
and the Administrative Agent and each of the Lenders acknowledges and agrees
that the Collateral has continued to secure the indebtedness, loans,
liabilities, expenses, and obligations under the Credit Agreement since the date
of execution of

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each applicable Loan Document, and all liens and security interests in the
Collateral that were granted pursuant to any of the Loan Documents shall remain
in full force and effect from and after the date hereof.

      5. Governing Law.

      This Amendment shall be deemed to be a contract under the laws of the
Commonwealth of Pennsylvania and for all purposes shall be governed by and
construed and enforced in accordance with the internal laws of the Commonwealth
of Pennsylvania without regard to its conflict of laws principles.

      6. Counterparts.

      This Amendment may be signed in any number of counterparts each of which
shall be deemed an original, but all of which together shall constitute one and
the same instrument.

                         [SIGNATURES BEGIN ON NEXT PAGE]

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          [SIGNATURE PAGE TO FIRST AMENDMENT TO ARCH COAL, INC. AMENDED
                         AND RESTATED CREDIT AGREEMENT]

      IN WITNESS WHEREOF, the parties hereto, by their officers thereunto duly
authorized, have executed this Amendment as of the day and year first above
written.

ATTEST:                                     ARCH COAL, INC.

/s/ Janet L. Horgan                         By: /s/ Robert J. Messey      [Seal]
---------------------------------              ---------------------------
Janet L. Horgan                             Name:  Robert J. Messey
Assistant Secretary                         Title: Senior Vice President and
                                                   Chief Financial Officer