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                                                                     EXHIBIT 4.7

                      SECOND AMENDMENT TO CREDIT AGREEMENT

      THIS SECOND AMENDMENT TO CREDIT AGREEMENT (THE "AMENDMENT"), dated and
effective as of January 30, 2004, is made by and among ARCH WESTERN RESOURCES,
LLC, a Delaware limited liability company (the "Borrower"), the LENDERS (as
hereinafter defined), and PNC BANK, NATIONAL ASSOCIATION, in its capacity as
administrative agent for the Lenders (hereinafter referred to in such capacity
as the "Agent").

                                   WITNESSETH:

      WHEREAS, the Borrower, PNC Bank, National Association, as administrative
agent, and certain lenders are parties to that Credit Agreement dated as of
September 19, 2003 as amended by that certain First Amendment to Credit
Agreement dated as of December 22, 2003 (the "Credit Agreement");

      WHEREAS, subject to the terms and conditions hereinafter provided, 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. Recitals.

            The foregoing recitals are true and correct and incorporated herein
by reference.

      2. Definitions.

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

      3. Amendment to Credit Agreement.

      (a) Section 1.1 Certain Definitions.

            (i) The following definition "Borrowing Date" contained in Section
      1.1 [Certain Definitions] of the Credit Agreement is hereby amended and
      restated in its entirety to read as follows:

                  "Borrowing Date shall mean the Business Day, occurring on or
            before May 17, 2004, on which the Term Loans shall be made, which
            date shall be the date that all of the conditions specified in
            Section 6.2 have been satisfied or waived."

            (ii) The following new definition is hereby added alphabetically to
      Section 1.1 [Certain Definitions of the Credit Agreement:
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            "Second Amendment Effective Date shall mean January 30, 2004."

                  Section 2.1.2 Commitment Fee. Section 2.1.2 [Commitment Fee]
            of the Credit Agreement is hereby amended and restated in its
            entirety to read as follows:

                  "Accruing from the Closing Date through and including the
            Borrowing Date, the Borrower agrees to pay to the Agent for the
            account of each Lender, as consideration for such Lender's
            Commitment hereunder, a nonrefundable commitment fee (the
            "Commitment Fee") equal to the following: (i) for that period from
            the Closing Date up to but excluding the Second Amendment Effective
            Date, twenty-five (25) basis points (computed on the basis of a year
            of 365 or 366 days, as the case may be, and actual days elapsed)
            computed on the amount of such Lender's Commitment, (ii) for that
            period from the Second Amendment Effective Date through and
            including the earlier of either March 31, 2004 or the Borrowing
            Date, fifty (50) basis points (computed on the basis of a year of
            365 or 366 days, as the case may be, and actual days elapsed)
            computed on the amount of such Lender's Commitment, and (iii) if the
            Borrowing Date occurs on April 1, 2004 or later, for that period
            from April 1, 2004 through and including the Borrowing Date,
            seventy-five (75) basis points (computed on the basis of a year of
            365 or 366 days, as the case may be, and actual days elapsed)
            computed on the amount of such Lender's Commitment. All Commitment
            Fees shall be payable in arrears on the first Business Day of each
            July, October, January and April after the date hereof and on the
            Expiration Date or upon acceleration of the Loans."

      (b) Section 2.5 Borrowing Date Procedure and Request to Select Interest
Rate Options. Section 2.5 [Borrowing Date Procedure, etc.] of the Credit
Agreement is hereby amended and restated in its entirety to read as follows:

                  "Except as otherwise provided herein, the Borrower may (a)
            designate the Borrowing Date (which date shall be a Business Day and
            which date shall be on or before May 17, 2004), (b) request the
            Lenders to make the Term Loans on the Borrowing Date and (c) select
            the initial Interest Rate Option applicable to the Term Loans and
            thereafter from time to time prior to the Expiration Date request
            the Lenders to renew or convert the Interest Rate Option applicable
            to existing Term Loans pursuant to Section 3.2 [Interest Periods],
            by delivering to the Agent, not later than 10:00 a.m., Pittsburgh
            time, (i) three (3) Business Days prior to the proposed Borrowing
            Date with respect to the making of the Term Loans on the Borrowing
            Date or the conversion to or the renewal of the Euro-Rate Option for
            any Term Loans, and (ii) one (1) Business Day prior to the making of
            the Term Loans on the Borrowing Date to which the Base Rate Option
            applies or the last day of the preceding Interest Period with
            respect to the conversion to the Base Rate Option for any Term Loan,
            of a duly completed request therefore substantially in the form of
            Exhibit 2.5 (each a "Rate Request") or a request
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            therefore by telephone immediately confirmed in writing by letter,
            facsimile or telex in the form of such Exhibit, it being understood
            that the Agent may rely on the authority of any individual making
            such a telephonic request without the necessity of receipt of such
            written confirmation. Each Rate Request shall be irrevocable and
            shall specify (i) the proposed Borrowing Date; (ii) the aggregate
            amount of the Term Loans comprising each Borrowing Tranche, which
            shall be in integral multiples of $500,000 and not less than
            $1,000,000 for each Borrowing Tranche to which the Euro-Rate Option
            applies and in integral multiples of $100,000 and not less than the
            lesser of $500,000 or the maximum amount available for Borrowing
            Tranches to which the Base Rate Option applies; (iii) whether the
            Euro-Rate Option or Base Rate Option shall apply to the applicable
            Borrowing Tranche; and (iv) in the case of a Borrowing Tranche to
            which the Euro-Rate Option applies, an appropriate Interest Period
            for the Term Loans comprising such Borrowing Tranche. The Agent
            shall, promptly after receipt by it of a Rate Request pursuant to
            this Section 2.5, notify the Lenders of its receipt of such Rate
            Request and provide each Lender with a copy thereof. The Loan
            Parties agree that no Lender shall have any Commitments or any other
            commitment or obligation to fund any portion of the Term Loans after
            May 17, 2004."

      (c) Section 6.2.14 Consummation of Vulcan Acquisition and North Rochelle
Contribution. Clause (iii) of Section 6.2.14 [Consummation of Vulcan Acquisition
and North Rochelle Contribution] is hereby amended and restated in its entirety
to read as follows:

                  "(iii) The acquisitions and transactions contemplated by the
            Vulcan Acquisition Documents and the North Rochelle Contribution
            Documents shall have been consummated in accordance with the terms
            of such documents on or prior to the Borrowing Date (which date
            shall be on or before May 17, 2004);"

      4. 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
Agent for itself the reasonable costs and expenses of the Agent including,
without limitation, reasonable fees of the Agent's counsel in connection with
this Amendment.

      (b) No Default. Confirmation of Representations and Warranties, etc. As of
the date hereof after giving effect to this Amendment, no Event of Default or
Potential Default shall have occurred. The Borrower, by executing this
Amendment, hereby certifies and confirms that as of the date hereof arid after
giving effect to this Amendment: (a) 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 certificate of
organization or its limited liability company operating agreement, (b) no Event
of Default or Potential Event of Default has
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occurred or would result from the execution, delivery and performance of this
Amendment, (c) 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), and (d) the Credit Agreement (as amended by this
Amendment) and all other Loan Documents are and remain legal, valid, binding and
enforceable obligations in accordance with the terms thereof

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

      (d) Organization. Authorization and Incumbency. There shall be delivered
to the 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 4 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 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 Agent remain in fill force
      and effect and have not been modified, amended or rescinded.

      (e) 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
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consummation of this Amendment.

      (f) Litigation. Except as disclosed in the schedules to the Credit
Agreement, 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 Agent's sole discretion, would make it inadvisable to consummate the
transactions contemplated by this Amendment or any of the other Loan Documents.

      (g) Legal Details. All legal details and proceedings in connection with
the transactions contemplated by this Amendment shall be in form and substance
satisfactory to the Agent, the Agent shall have received from the Borrower and
the Lenders an executed original of this Amendment and the 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 Agent.

      This Amendment shall be dated as of and shall become effective on the date
that (such date being hereinafter referred to as the "Second Amendment Effective
Date"): (i) it has been duly executed by the Borrower, the Agent and the
Required Lenders, and (ii) each of the conditions set forth in this Section 4
has been satisfied.

      5. Force and Effect.

      No novation is intended or shall occur by or as a result of this
Amendment. The Borrower reconfirms, restates and ratifies the Credit Agreement
(as amended by this Amendment), each of the other Loan Documents and all other
documents executed in connection therewith, and the Borrower confirms that all
such documents have remained in full force and effect since the date of their
execution. 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 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 each applicable Loan Document, and all
liens and security interests in the Collateral which were granted pursuant to
any of the Loan Documents shall remain in full force and effect from and after
the date hereof.

      6. 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.
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      7. 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.

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