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                                                                     EXHIBIT 4.4

                            ARCH WESTERN FINANCE, LLC

                          6 3/4% SENIOR NOTES DUE 2013

                          REGISTRATION RIGHTS AGREEMENT

                                                              New York, New York

                                                                   June 25, 2003

Citigroup Global Markets Inc.
J.P. Morgan Securities Inc.
Morgan Stanley & Co. Incorporated
As Representatives of the Initial Purchasers
c/o Citigroup Global Markets Inc.
    388 Greenwich Street
    New York, New York 10013

Dear Sirs:

                  Arch Western Finance, LLC, a limited liability company
organized under the laws of Delaware (the "Issuer"), proposes to issue and sell
to certain purchasers (the "Initial Purchasers"), upon the terms set forth in a
Purchase Agreement dated June 19, 2003 (the "Purchase Agreement") relating to
the initial placement (the "Initial Placement") of the Issuer's 6 3/4% Senior
Notes due 2013 (the "Notes"). The Notes will be fully and unconditionally
guaranteed as to payment of principal, premium if any, and interest (the
"Guarantees" and together with the Notes hereinafter referred to as the
"Securities") by Arch Western Resources, LLC, a limited liability company
organized under the laws of Delaware ("Arch Western") and the Subsidiary
Guarantors listed in Schedule II to the Purchase Agreement. Arch Western and the
Subsidiary Guarantors are hereinafter referred to as the "Guarantors". To induce
the Initial Purchasers to enter into the Purchase Agreement and to satisfy a
condition of your obligations thereunder, each of the Issuer, Arch Coal, Inc., a
corporation organized under the laws of Delaware (the "Company"), and the
Guarantors, jointly and severally, agrees with you for your benefit and the
benefit of the holders from time to time of the Securities (including the
Initial Purchasers) (each a "Holder" and, together, the "Holders"), as follows:

                  1.       Definitions. Capitalized terms used herein without
definition shall have their respective meanings set forth in the Purchase
Agreement. As used in this Agreement, the following capitalized defined terms
shall have the following meanings:

                  "Act" shall mean the Securities Act of 1933, as amended, and
the rules and regulations of the Commission promulgated thereunder.

                  "Affiliate" of any specified Person shall mean any other
Person that, directly or indirectly, is in control of, is controlled by, or is
under common control with, such specified Person. For purposes of this
definition, control of a Person shall mean the power, direct or

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indirect, to direct or cause the direction of the management and policies of
such Person whether by contract or otherwise; and the terms "controlling" and
"controlled" shall have meanings correlative to the foregoing.

                  "Arch Western" shall have the meaning set forth in the
preamble hereto.

                  "Broker-Dealer" shall mean any broker or dealer registered as
such under the Exchange Act.

                  "Business Day" shall mean any day other than a Saturday, a
Sunday or a legal holiday or a day on which banking institutions or trust
companies are authorized or obligated by law to close in New York City.

                  "Commission" shall mean the Securities and Exchange
Commission.

                  "Company" shall have the meaning set forth in the preamble
hereto.

                  "Exchange Act" shall mean the Securities Exchange Act of 1934,
as amended, and the rules and regulations of the Commission promulgated
thereunder.

                  "Exchange Offer Registration Period" shall mean the one-year
period following the consummation of the Registered Exchange Offer, exclusive of
any period during which any stop order shall be in effect suspending the
effectiveness of the Exchange Offer Registration Statement.

                  "Exchange Offer Registration Statement" shall mean a
registration statement of each of the Issuer and the Guarantors on an
appropriate form under the Act with respect to the Registered Exchange Offer,
all amendments and supplements to such registration statement, including
post-effective amendments thereto, in each case including the Prospectus
contained therein, all exhibits thereto and all material incorporated by
reference therein.

                  "Exchanging Dealer" shall mean any Holder (which may include
any Initial Purchaser) that is a Broker-Dealer and elects to exchange for New
Securities any Securities that it acquired for its own account as a result of
market-making activities or other trading activities (but not directly from the
Issuer or any Guarantor or any Affiliate of the Issuer or any Guarantor) for New
Securities.

                  "Final Memorandum" shall have the meaning set forth in the
Purchase Agreement.

                  "Guarantors" shall have the meaning set forth in the preamble
hereto.

                  "Holder" shall have the meaning set forth in the preamble
hereto.

                  "Indenture" shall mean the Indenture relating to the
Securities, dated as of June 25, 2003, among each of the Issuer, the Guarantors
and the Bank of New York, as trustee, as the same may be amended from time to
time in accordance with the terms thereof.

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                  "Initial Placement" shall have the meaning set forth in the
preamble hereto.

                  "Initial Purchaser" shall have the meaning set forth in the
preamble hereto.

                  "Issuer" shall have the meaning set forth in the preamble
hereto.

                  "Losses" shall have the meaning set forth in Section 6(d)
hereof.

                  "Majority Holders" shall mean the Holders of a majority of the
aggregate principal amount of Securities registered under a Registration
Statement.

                  "Managing Underwriters" shall mean the investment banker or
investment bankers and manager or managers that shall administer an underwritten
offering.

                  "New Securities" shall mean debt securities of the Issuer
identical in all material respects to the Securities (except that the cash
interest and interest rate step-up provisions and the transfer restrictions
shall be modified or eliminated, as appropriate) and to be issued under the
Indenture or the New Securities Indenture.

                  "New Securities Indenture" shall mean an indenture among each
of the Issuer, the Guarantors and the New Securities Trustee, identical in all
material respects to the Indenture (except that the cash interest and interest
rate step-up provisions will be modified or eliminated, as appropriate).

                  "New Securities Trustee" shall mean a bank or trust company
reasonably satisfactory to the Initial Purchasers, as trustee with respect to
the New Securities under the New Securities Indenture.

                  "Notes" shall have the meaning set forth in the preamble
hereto.

                  "Prospectus" shall mean the prospectus included in any
Registration Statement (including, without limitation, a prospectus that
discloses information previously omitted from a prospectus filed as part of an
effective registration statement in reliance upon Rule 430A under the Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Securities or the New Securities covered
by such Registration Statement, and all amendments and supplements thereto and
all material incorporated by reference therein.

                  "Purchase Agreement" shall have the meaning set forth in the
preamble hereto.

                  "Registered Exchange Offer" shall mean the proposed offer of
the Issuer and the Guarantors to issue and deliver to the Holders of the
Securities that are not prohibited by any law or policy of the Commission from
participating in such offer, in exchange for the Securities, a like aggregate
principal amount of the New Securities.

                  "Registration Statement" shall mean any Exchange Offer
Registration Statement or Shelf Registration Statement that covers any of the
Securities or the New Securities pursuant to the provisions of this Agreement,
any amendments and supplements to such registration

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statement, including post-effective amendments (in each case including the
Prospectus contained therein), all exhibits thereto and all material
incorporated by reference therein.

                  "Securities" shall have the meaning set forth in the preamble
hereto.

                  "Shelf Registration" shall mean a registration effected
pursuant to Section 3 hereof.

                  "Shelf Registration Period" has the meaning set forth in
Section 3(b) hereof.

                  "Shelf Registration Statement" shall mean a "shelf"
registration statement of the Issuer and the Guarantors pursuant to the
provisions of Section 3 hereof which covers some or all of the Securities or New
Securities, as applicable, on an appropriate form under Rule 415 under the Act,
or any similar rule that may be adopted by the Commission, amendments and
supplements to such registration statement, including post-effective amendments,
in each case including the Prospectus contained therein, all exhibits thereto
and all material incorporated by reference therein.

                  "Subsidiary Guarantor" shall have the meaning set forth in the
preamble hereto.

                  "Trustee" shall mean the trustee with respect to the
Securities under the Indenture.

                  "underwriter" shall mean any underwriter of Securities in
connection with an offering thereof under a Shelf Registration Statement.

                  2.       (a) Unless prohibited under applicable law or policy
of the Commission, the Issuer, the Company and the Guarantors shall prepare and,
not later than 90 days following the date of the original issuance of the
Securities (or if such 90th day is not a Business Day, the next succeeding
Business Day), the Issuer and the Guarantors shall file with the Commission the
Exchange Offer Registration Statement with respect to the Registered Exchange
Offer. The Issuer, the Company and the Guarantors shall use their reasonable
best efforts to cause the Exchange Offer Registration Statement to become
effective under the Act within 180 days of the date of the original issuance of
the Securities (or if such 180th day is not a Business Day, the next succeeding
Business Day).

                  (b)      Upon the effectiveness of the Exchange Offer
Registration Statement, the Issuer, the Company and the Guarantors shall
promptly commence the Registered Exchange Offer, it being the objective of such
Registered Exchange Offer to enable each Holder electing to exchange Securities
for New Securities (assuming that such Holder is not an Affiliate of the Issuer
or any Guarantor, acquires the New Securities in the ordinary course of such
Holder's business, has no arrangements with any Person to participate in the
distribution of the New Securities and is not prohibited by any law or policy of
the Commission from participating in the Registered Exchange Offer) to trade
such New Securities from and after their receipt without any limitations or
restrictions under the Act and without material restrictions under the
securities laws of a substantial proportion of the several states of the United
States.

                  (c)      In connection with the Registered Exchange Offer, the
Issuer, the Company and the Guarantors shall:

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                           (i)      mail to each Holder a copy of the Prospectus
         forming part of the Exchange Offer Registration Statement, together
         with an appropriate letter of transmittal and related documents;

                           (ii)     keep the Registered Exchange Offer open for
         not less than 30 Business Days and not more than 45 Business Days after
         the date notice thereof is mailed to the Holders (or, in each case,
         longer if required by applicable law);

                           (iii)    use their reasonable best efforts to keep
         the Exchange Offer Registration Statement continuously effective under
         the Act, supplemented and amended as required, under the Act to ensure
         that it is available for sales of New Securities by Exchanging Dealers
         during the Exchange Offer Registration Period;

                           (iv)     utilize the services of a depositary for the
         Registered Exchange Offer with an address in the Borough of Manhattan
         in New York City, which may be the Trustee, the New Securities Trustee
         or an Affiliate of either of them;

                           (v)      permit Holders to withdraw tendered
         Securities at any time prior to the close of business, New York time,
         on the last Business Day on which the Registered Exchange Offer is
         open;

                           (vi)     prior to effectiveness of the Exchange Offer
         Registration Statement, provide a supplemental letter to the Commission
         (A) stating that the Issuer and the Guarantors are conducting the
         Registered Exchange Offer in reliance on the position of the Commission
         in Exxon Capital Holdings Corporation (pub. avail. May 13, 1988),
         Morgan Stanley and Co., Inc. (pub. avail. June 5, 1991); and (B)
         including a representation that each of the Issuer and the Guarantors
         has not entered into any arrangement or understanding with any Person
         to distribute the New Securities to be received in the Registered
         Exchange Offer and that, to the best of each of the Issuer's and the
         Guarantors' information and belief, each Holder participating in the
         Registered Exchange Offer is acquiring the New Securities in the
         ordinary course of business and has no arrangement or understanding
         with any Person to participate in the distribution of the New
         Securities; and

                           (vii)    comply in all material respects with all
         applicable laws.

                  (d)      As soon as practicable after the close of the
Registered Exchange Offer, the Issuer and the Guarantors shall:

                            (i)     accept for exchange all Securities tendered
         and not validly withdrawn pursuant to the Registered Exchange Offer;

                            (ii)    deliver to the Trustee for cancellation in
         accordance with Section 4(s) all Securities so accepted for exchange;
         and

                            (iii)   cause the New Securities Trustee promptly to
         authenticate and deliver to each Holder of Securities a principal
         amount of New Securities equal to the principal amount of the
         Securities of such Holder so accepted for exchange.

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                  (e)      Each Holder hereby acknowledges and agrees that any
Broker-Dealer and any such Holder using the Registered Exchange Offer to
participate in a distribution of the New Securities (x) could not under
Commission policy as in effect on the date of this Agreement rely on the
position of the Commission in Morgan Stanley and Co., Inc. (pub. avail. June 5,
1991) and Exxon Capital Holdings Corporation (pub. avail. May 13, 1988), as
interpreted in the Commission's letter to Shearman & Sterling dated July 2, 1993
and similar no-action letters; and (y) must comply with the registration and
prospectus delivery requirements of the Act in connection with any secondary
resale transaction must be covered by an effective registration statement
containing the selling security holder information required by Item 507 or 508,
as applicable, of Regulation S-K under the Act if the resales are of New
Securities obtained by such Holder in exchange for Securities acquired by such
Holder directly from the Company or one of its Affiliates. Accordingly, each
Holder participating in the Registered Exchange Offer shall be required to
represent to the Issuer and the Guarantors that, at the time of the consummation
of the Registered Exchange Offer:

                           (i)      any New Securities received by such Holder
         will be acquired in the ordinary course of business;

                           (ii)     such Holder will have no arrangement or
         understanding with any Person to participate in the distribution of the
         Securities or the New Securities within the meaning of the Act; and

                           (iii)    such Holder is not an Affiliate of the
         Issuer or any Guarantor.

                  (f)      If any Initial Purchaser determines that it is not
eligible to participate in the Registered Exchange Offer with respect to the
exchange of Securities constituting any portion of an unsold allotment, at the
request of such Initial Purchaser, the Issuer, the Company and the Guarantors
shall issue and deliver to such Initial Purchaser or the Person purchasing New
Securities registered under a Shelf Registration Statement as contemplated by
Section 3 hereof from such Initial Purchaser, in exchange for such Securities, a
like principal amount of New Securities. The Issuer, the Company and the
Guarantors shall use their reasonable best efforts to cause the CUSIP Service
Bureau to issue the same CUSIP number for such New Securities as for New
Securities issued pursuant to the Registered Exchange Offer.

                  3.       Shelf Registration. (a) If (i) due to any change in
law or applicable interpretations thereof by the Commission's staff, the Issuer,
the Company and the Guarantors determines upon advice of their outside counsel
that they are not permitted to effect the Registered Exchange Offer as
contemplated by Section 2 hereof; (ii) for any other reason the Registered
Exchange Offer is not consummated within 225 days of the date hereof; (iii) any
Initial Purchaser so requests with respect to Securities that are not eligible
to be exchanged for New Securities in the Registered Exchange Offer and that are
held by it following consummation of the Registered Exchange Offer; (iv) any
Holder (other than an Initial Purchaser) is not eligible to participate in the
Registered Exchange Offer; or (v) in the case of any Initial Purchaser that
participates in the Registered Exchange Offer or acquires New Securities
pursuant to Section 2(f) hereof, such Initial Purchaser does not receive freely
tradeable New Securities in exchange for Securities constituting any portion of
an unsold allotment (it being understood that (x) the requirement that an
Initial Purchaser deliver a Prospectus containing the information required by

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Item 507 or 508 of Regulation S-K under the Act in connection with sales of New
Securities acquired in exchange for such Securities shall result in such New
Securities being not "freely tradeable"; and (y) the requirement that an
Exchanging Dealer deliver a Prospectus in connection with sales of New
Securities acquired in the Registered Exchange Offer in exchange for Securities
acquired as a result of market-making activities or other trading activities
shall not result in such New Securities being not "freely tradeable"), the
Issuer, the Company and the Guarantors shall effect a Shelf Registration
Statement in accordance with subsection (b) below.

                  (b)      (i) The Issuer and the Guarantors shall as promptly
as practicable (but in no event more than 60 days after so required or requested
pursuant to this Section 3), file with the Commission and thereafter the Issuer,
the Company and the Guarantors shall use their reasonable best efforts to cause
to be declared effective under the Act a Shelf Registration Statement relating
to the offer and sale of the Securities or the New Securities, as applicable, by
the Holders thereof from time to time in accordance with the methods of
distribution elected by such Holders and set forth in such Shelf Registration
Statement; provided, however, that no Holder (other than an Initial Purchaser)
shall be entitled to have the Securities held by it covered by such Shelf
Registration Statement unless such Holder agrees in writing to be bound by all
of the provisions of this Agreement applicable to such Holder; and provided
further, that with respect to New Securities received by an Initial Purchaser in
exchange for Securities constituting any portion of an unsold allotment, the
Issuer and the Guarantors may, if permitted by current interpretations by the
Commission's staff, file a post-effective amendment to the Exchange Offer
Registration Statement containing the information required by Item 507 or 508 of
Regulation S-K, as applicable, in satisfaction of their obligations under this
subsection with respect thereto, and any such Exchange Offer Registration
Statement, as so amended, shall be referred to herein as, and governed by the
provisions herein applicable to, a Shelf Registration Statement.

                           (ii)     The Issuer, the Company and the Guarantors
         shall use their reasonable best efforts to keep the Shelf Registration
         Statement continuously effective, supplemented and amended as required
         by the Act, in order to permit the Prospectus forming part thereof to
         be usable by Holders for a period of two years from the date the Shelf
         Registration Statement is declared effective by the Commission or such
         shorter period that will terminate when all the Securities or New
         Securities, as applicable, covered by the Shelf Registration Statement
         have been sold pursuant to the Shelf Registration Statement (in any
         such case, such period being called the "Shelf Registration Period").
         Each of the Issuer, the Company and the Guarantors shall be deemed not
         to have used its reasonable best efforts to keep the Shelf Registration
         Statement effective during the requisite period if it voluntarily takes
         any action that would result in Holders of Securities covered thereby
         not being able to offer and sell such Securities during that period,
         unless (A) such action is required by applicable law; or (B) such
         action is taken by the Issuer, the Company and the Guarantors in good
         faith and for valid business reasons (not including avoidance of the
         Issuer's, the Company's and Guarantors' obligations hereunder),
         including the acquisition or divestiture of assets, so long as each of
         the Issuer, the Company and the Guarantors promptly thereafter complies
         with the requirements of Section 4(k) hereof, if applicable.

                           (iii)    The Issuer, the Company and the Guarantors
         shall cause the Shelf Registration Statement and the related Prospectus
         and any amendment or supplement

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         thereto, as of the effective date of the Shelf Registration Statement
         or such amendment or supplement, (A) to comply in all material respects
         with the applicable requirements of the Securities Act and the rules
         and regulations of the Commission; and (B) not to contain any untrue
         statement of a material fact or omit to state a material fact required
         to be stated therein or necessary in order to make the statements
         therein, in the light of the circumstances under which they were made,
         not misleading.

                  4.       Additional Registration Procedures. In connection
with any Shelf Registration Statement and, to the extent applicable, any
Exchange Offer Registration Statement, the following provisions shall apply.

                  (a)      The Issuer, the Company and the Guarantors shall:

                           (i)      furnish to you, not less than five Business
         Days prior to the filing thereof with the Commission, a copy of any
         Shelf Registration Statement, and each amendment thereof and each
         amendment or supplement, if any, to the Prospectus included therein
         (including all documents incorporated by reference therein after the
         initial filing) and shall use their best efforts to reflect in each
         such document, when so filed with the Commission, such comments as you
         reasonably propose;

                           (ii)     include the information set forth in Annex A
         hereto on the facing page of the Exchange Offer Registration Statement,
         in Annex B hereto in the forepart of the Exchange Offer Registration
         Statement in a section setting forth details of the Exchange Offer, in
         Annex C hereto in the underwriting or plan of distribution section of
         the Prospectus contained in the Exchange Offer Registration Statement,
         and in Annex D hereto in the letter of transmittal delivered pursuant
         to the Registered Exchange Offer;

                           (iii)    if requested by an Initial Purchaser,
         include the information required by Item 507 or 508 of Regulation S-K,
         as applicable, in the Prospectus contained in the Exchange Offer
         Registration Statement; and

                           (iv)     in the case of a Shelf Registration
         Statement, include the names of the Holders that propose to sell
         Securities pursuant to the Shelf Registration Statement as selling
         security holders.

                  (b)      The Issuer, the Company and the Guarantors shall
ensure that:

                           (i)      any Registration Statement and any amendment
         thereto and any Prospectus forming part thereof and any amendment or
         supplement thereto complies in all material respects with the Act and
         the rules and regulations thereunder; and

                           (ii)     any Registration Statement and any amendment
         thereto does not, when it becomes effective, contain an untrue
         statement of a material fact or omit to state a material fact required
         to be stated therein or necessary to make the statements therein not
         misleading.

                  (c)      The Company shall advise you, the Holders of
Securities covered by any Shelf Registration Statement and any Exchanging Dealer
under any Exchange Offer Registration

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Statement that has been provided in writing to the Company a telephone or
facsimile number and address for notices, and, if requested by you or any such
Holder or Exchanging Dealer, shall confirm such advice in writing (which notice
pursuant to clauses (ii)-(v) hereof shall be accompanied by an instruction to
suspend the use of the Prospectus until the Issuer and the Guarantors shall have
remedied the basis for such suspension):

                           (i)      when a Registration Statement and any
         amendment thereto has been filed with the Commission and when the
         Registration Statement or any post-effective amendment thereto has
         become effective;

                           (ii)     of any request by the Commission for any
         amendment or supplement to the Registration Statement or the Prospectus
         or for additional information;

                           (iii)    of the issuance by the Commission of any
         stop order suspending the effectiveness of the Registration Statement
         or the initiation of any proceedings for that purpose;

                           (iv)     of the receipt by the Issuer, the Company or
         any Guarantor of any notification with respect to the suspension of the
         qualification of the securities included therein for sale in any
         jurisdiction or the initiation of any proceeding for such purpose; and

                           (v)      of the happening of any event that requires
         any change in the Registration Statement or the Prospectus so that, as
         of such date, the statements therein are not misleading and do not omit
         to state a material fact required to be stated therein or necessary to
         make the statements therein (in the case of the Prospectus, in the
         light of the circumstances under which they were made) not misleading.

                  (d)      The Issuer, the Company and the Guarantors shall use
their reasonable best efforts to obtain the withdrawal of any order suspending
the effectiveness of any Registration Statement or the qualification of the
securities therein for sale in any jurisdiction at the earliest possible time.

                  (e)      The Issuer, the Company and the Guarantors shall
furnish to each Holder of Securities covered by any Shelf Registration
Statement, without charge, at least one copy of such Shelf Registration
Statement and any post-effective amendment thereto, including all material
incorporated therein by reference, and, if the Holder so requests in writing,
all exhibits thereto (including exhibits incorporated by reference therein).

                  (f)      The Issuer, the Company and the Guarantors shall,
during the Shelf Registration Period, deliver to each Holder of Securities
covered by any Shelf Registration Statement, without charge, as many copies of
the Prospectus (including each preliminary Prospectus) included in such Shelf
Registration Statement and any amendment or supplement thereto as such Holder
may reasonably request. Each of the Issuer and the Guarantors consents to the
use of the Prospectus or any amendment or supplement thereto by each of the
selling Holders of securities in connection with the offering and sale of the
securities covered by the Prospectus, or any amendment or supplement thereto,
included in the Shelf Registration Statement.

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                  (g)      The Issuer, the Company and the Guarantors shall
furnish to each Exchanging Dealer which so requests, without charge, at least
one copy of the Exchange Offer Registration Statement and any post-effective
amendment thereto, including all material incorporated by reference therein,
and, if the Exchanging Dealer so requests in writing, all exhibits thereto
(including exhibits incorporated by reference therein).

                  (h)      The Issuer, the Company and the Guarantors shall
promptly deliver to each Initial Purchaser, each Exchanging Dealer and each
other Person required to deliver a Prospectus during the Exchange Offer
Registration Period, without charge, as many copies of the Prospectus included
in such Exchange Offer Registration Statement and any amendment or supplement
thereto as any such Person may reasonably request. Each of the Issuer, the
Company and the Guarantors consents to the use of the Prospectus or any
amendment or supplement thereto by any Initial Purchaser, any Exchanging Dealer
and any such other Person that may be required to deliver a Prospectus following
the Registered Exchange Offer in connection with the offering and sale of the
New Securities covered by the Prospectus, or any amendment or supplement
thereto, included in the Exchange Offer Registration Statement.

                  (i)      Prior to the Registered Exchange Offer or any other
offering of Securities pursuant to any Registration Statement, the Issuer, the
Company and the Guarantors shall use their reasonable best efforts to arrange,
if necessary, for the qualification of the Securities or the New Securities for
sale under the laws of such jurisdictions as any Holder shall reasonably request
and will maintain such qualification in effect so long as required to enable the
offer and sale in such jurisdictions of the Securities or New Securities;
provided that in no event shall the Issuer, the Company or the Guarantors be
obligated to qualify to do business in any jurisdiction where they are not then
so qualified or to take any action that would subject them to service of process
in suits, other than those arising out of the Initial Placement, the Registered
Exchange Offer or any offering pursuant to a Shelf Registration Statement, in
any such jurisdiction where they are not then so subject.

                  (j)      The Issuer, the Company and the Guarantors shall
cooperate with the Holders of Securities to facilitate the timely preparation
and delivery of certificates representing New Securities or Securities to be
issued or sold pursuant to any Registration Statement free of any restrictive
legends and in such denominations and registered in such names as Holders may
request.

                  (k)      Upon the occurrence of any event contemplated by
subsections (c)(ii) through (v) above during the period for which the Issuer,
the Company and the Guarantors are required under this Agreement to maintain an
effective Registration Statement. The Issuer, the Company and the Guarantors
shall promptly prepare a post-effective amendment to the applicable Registration
Statement or an amendment or supplement to the related Prospectus or file any
other required document so that, as thereafter delivered to Initial Purchasers
of the securities included therein, the Prospectus will not include an untrue
statement of a material fact or omit to state any material fact necessary to
make the statements therein, in the light of the circumstances under which they
were made, not misleading. In such circumstances, the period of effectiveness of
the Exchange Offer Registration Statement provided for in Section 2 and the
Shelf Registration Statement provided for in Section 3(b) shall each be extended
by the number of days from and including the date of the giving of a notice of
suspension pursuant to Section

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4(c) to and including the date when the Initial Purchasers, the Holders of the
Securities and any known Exchanging Dealer shall have received such amended or
supplemented Prospectus pursuant to this Section.

                  (l)      Not later than the effective date of any Registration
Statement, the Issuer, the Company and the Guarantors shall provide a CUSIP
number for the Securities or the New Securities, as the case may be, registered
under such Registration Statement and provide the Trustee with printed
certificates for such Securities or New Securities, in a form eligible for
deposit with The Depository Trust Company.

                  (m)      The Issuer, the Company and the Guarantors shall
comply with all applicable rules and regulations of the Commission and shall
make generally available to their security holders as soon as practicable after
the effective date of the applicable Registration Statement an earnings
statement satisfying the provisions of Section 11(a) of the Act.

                  (n)      The Issuer and the Guarantors shall cause the
Indenture or the New Securities Indenture, as the case may be, to be qualified
under the Trust Indenture Act, as required by applicable law, in a timely
manner.

                  (o)      The Issuer and the Guarantors may require each Holder
of securities to be sold pursuant to any Shelf Registration Statement to furnish
to the Issuer and the Guarantors such information regarding the Holder and the
distribution of such securities as the Issuer and the Guarantors may from time
to time reasonably require for inclusion in such Registration Statement. The
Issuer and the Guarantors may exclude from such Shelf Registration Statement the
Securities of any Holder that fails to furnish such information within a
reasonable time after receiving such request.

                  (p)      In the case of any Shelf Registration Statement, the
Issuer, the Company and the Guarantors shall enter into such and take all other
appropriate actions (including if requested an underwriting agreement in
customary form) in order to expedite or facilitate the registration or the
disposition of the Securities, and in connection therewith, if an underwriting
agreement is entered into, cause the same to contain indemnification provisions
and procedures no less favorable than those set forth in Section 6 (or such
other provisions and procedures acceptable to the Majority Holders and the
Managing Underwriters, if any, with respect to all parties to be indemnified
pursuant to Section 6.

                  (q)      In the case of any Shelf Registration Statement, each
of the Issuer, the Company and the Guarantors shall:

                           (i)      make reasonably available for inspection by
         the Holders of Securities to be registered thereunder, any underwriter
         participating in any disposition pursuant to such Registration
         Statement, and any attorney, accountant or other agent retained by the
         Holders or any such underwriter all relevant financial and other
         records, pertinent corporate documents and properties of the Company
         and its subsidiaries;

                           (ii)     cause the Company's and Arch Western's
         respective officers, directors and employees to supply all relevant
         information reasonably requested by the Holders or any such
         underwriter, attorney, accountant or agent in connection with any

                                       11

<PAGE>

         such Registration Statement as is customary for similar due diligence
         examinations; provided, however, that any information that is
         designated in writing by the Company or Arch Western, in good faith, as
         confidential at the time of delivery of such information shall be kept
         confidential by the Holders or any such underwriter, attorney,
         accountant or agent, unless such disclosure is made in connection with
         a court proceeding or required by law, or such information becomes
         available to the public generally or through a third party without an
         accompanying obligation of confidentiality;

                           (iii)    make such representations and warranties to
         the Holders of Securities registered thereunder and the underwriters,
         if any, in form, substance and scope as are customarily made by issuers
         to underwriters in primary underwritten offerings and covering matters
         including, but not limited to, those set forth in the Purchase
         Agreement;

                           (iv)     obtain opinions of counsel to the Issuer,
         the Company and the Guarantors and updates thereof (which counsel and
         opinions (in form, scope and substance) shall be reasonably
         satisfactory to the Managing Underwriters, if any) addressed to each
         selling Holder and the underwriters, if any, covering such matters as
         are customarily covered in opinions requested in underwritten offerings
         and such other matters as may be reasonably requested by such Holders
         and underwriters;

                           (v)      obtain "cold comfort" letters and updates
         thereof from the independent certified public accountants of the
         Company, Arch Western and Canyon Fuel Company, LLC (and, if necessary,
         any other independent certified public accountants of any subsidiary of
         the Company or of any business acquired by the Company for which
         financial statements and financial data are, or are required to be,
         included in the Registration Statement), addressed to each selling
         Holder of Securities registered thereunder and the underwriters, if
         any, in customary form and covering matters of the type customarily
         covered in "cold comfort" letters in connection with primary
         underwritten offerings; and

                           (vi)     deliver such documents and certificates as
         may be reasonably requested by the Majority Holders and the Managing
         Underwriters, if any, including those to evidence compliance with
         Section 4(k) and with any customary conditions contained in the
         underwriting agreement or other agreement entered into by the Issuer,
         the Company and the Guarantors.

The actions set forth in clauses (iii), (iv), (v) and (vi) of this Section shall
be performed at (A) the effectiveness of such Registration Statement and each
post-effective amendment thereto; and (B) each closing under any underwriting or
similar agreement as and to the extent required thereunder.

                  (r)      In the case of any Exchange Offer Registration
Statement, each of the Issuer, the Company and the Guarantors shall, for any
Initial Purchaser which is exchanging Securities for New Securities in the
Exchange Offer:

                                       12

<PAGE>

                           (i)      make reasonably available for inspection by
         such Initial Purchaser, and any attorney, accountant or other agent
         retained by such Initial Purchaser, all relevant financial and other
         records, pertinent corporate documents and properties of the Company,
         Arch Western and their respective subsidiaries;

                           (ii)     cause the Company's and Arch Western's
         respective officers, directors and employees to supply all relevant
         information reasonably requested by such Initial Purchaser or any such
         attorney, accountant or agent in connection with any such Registration
         Statement as is customary for similar due diligence examinations;
         provided, however, that any information that is designated in writing
         by the Company and Arch Western, in good faith, as confidential at the
         time of delivery of such information shall be kept confidential by such
         Initial Purchaser or any such attorney, accountant or agent, unless
         such disclosure is made in connection with a court proceeding or
         required by law, or such information becomes available to the public
         generally or through a third party without an accompanying obligation
         of confidentiality;

                           (iii)    make such representations and warranties to
         such Initial Purchaser, in form, substance and scope as are customarily
         made by issuers to underwriters in primary underwritten offerings and
         covering matters including, but not limited to, those set forth in the
         Purchase Agreement;

                           (iv)     obtain opinions of counsel to the Issuer,
         the Company and the Guarantors and updates thereof (which counsel and
         opinions (in form, scope and substance) shall be reasonably
         satisfactory to such Initial Purchaser and its counsel, addressed to
         such Initial Purchaser, covering such matters as are customarily
         covered in opinions requested in underwritten offerings and such other
         matters as may be reasonably requested by such Initial Purchaser or its
         counsel;

                           (v)      obtain "cold comfort" letters and updates
         thereof from the independent certified public accountants of the
         Company, Arch Western and Canyon Fuel Company, LLC (and, if necessary,
         any other independent certified public accountants of any subsidiary of
         the Company or of any business acquired by the Company for which
         financial statements and financial data are, or are required to be,
         included in the Registration Statement), addressed to such Initial
         Purchaser, in customary form and covering matters of the type
         customarily covered in "cold comfort" letters in connection with
         primary underwritten offerings, or if requested by such Initial
         Purchaser or its counsel in lieu of a "cold comfort" letter, an
         agreed-upon procedures letter under Statement on Auditing Standards No.
         35, covering matters requested by such Initial Purchaser or its
         counsel; and

                           (vi)     deliver such documents and certificates as
         may be reasonably requested by such Initial Purchaser or its counsel,
         including those to evidence compliance with Section 4(k) and with
         conditions customarily contained in underwriting agreements.

The foregoing actions set forth in clauses (iii), (iv), (v), and (vi) of this
Section shall be performed at the close of the Registered Exchange Offer and the
effective date of any post-effective amendment to the Exchange Offer
Registration Statement.

                                       13

<PAGE>

                  (s)      If a Registered Exchange Offer is to be consummated,
upon delivery of the Securities by Holders to the Issuer and the Guarantors (or
to such other Person as directed by the Issuer and the Guarantors) in exchange
for the New Securities, the Issuer and the Guarantors shall mark, or caused to
be marked, on the Securities so exchanged that such Securities are being
canceled in exchange for the New Securities. In no event shall the Securities be
marked as paid or otherwise satisfied.

                  (t)      The Issuer, the Company and the Guarantors shall use
their best efforts (i) if the Securities have been rated prior to the initial
sale of such Securities, to confirm such ratings will apply to the Securities or
the New Securities, as the case may be, covered by a Registration Statement; or
(ii) if the Securities were not previously rated, to cause the Securities
covered by a Registration Statement to be rated with at least one nationally
recognized statistical rating agency, if so requested by Majority Holders with
respect to the related Registration Statement or by any Managing Underwriters.

                  (u)      In the event that any Broker-Dealer shall underwrite
any Securities or participate as a member of an underwriting syndicate or
selling group or "assist in the distribution" (within the meaning of the Rules
of Fair Practice and the By-Laws of the National Association of Securities
Dealers, Inc.) thereof, whether as a Holder of such Securities or as an
underwriter, a placement or sales agent or a broker or dealer in respect
thereof, or otherwise, assist such Broker-Dealer in complying with the
requirements of such Rules and By-Laws, including, without limitation, by:

                           (i)      if such Rules or By-Laws shall so require,
         engaging a "qualified independent underwriter" (as defined in such
         Rules) to participate in the preparation of the Registration Statement,
         to exercise usual standards of due diligence with respect thereto and,
         if any portion of the offering contemplated by such Registration
         Statement is an underwritten offering or is made through a placement or
         sales agent, to recommend the yield of such Securities;

                           (ii)     indemnifying any such qualified independent
         underwriter to the extent of the indemnification of underwriters
         provided in Section 6 hereof; and

                           (iii)    providing such information to such
         Broker-Dealer as may be required in order for such Broker-Dealer to
         comply with the requirements of such Rules.

                           (iv)     The Issuer, the Company and the Guarantors
         shall use their best efforts to take all other steps necessary to
         effect the registration of the Securities or the New Securities, as the
         case may be, covered by a Registration Statement.

                  5.       Registration Expenses. The Issuer, the Company and
the Guarantors shall bear all expenses incurred in connection with the
performance of their obligations under Sections 2, 3 and 4 hereof and, in the
event of any Shelf Registration Statement, will reimburse the Holders for the
reasonable fees and disbursements of one firm or counsel designated by the
Majority Holders to act as counsel for the Holders in connection therewith, and,
in the case of any Exchange Offer Registration Statement, will reimburse the
Initial Purchasers for the reasonable fees and disbursements of counsel acting
in connection therewith.

                                       14

<PAGE>

                  6.       Indemnification and Contribution. (a) Each of the
Issuer, the Company and the Guarantors agrees, jointly and severally, to
indemnify and hold harmless each Holder of Securities or New Securities, as the
case may be, covered by any Registration Statement (including each Initial
Purchaser and, with respect to any Prospectus delivery as contemplated in
Section 4(h) hereof, each Exchanging Dealer), the directors, officers, employees
and agents of each such Holder and each Person who controls any such Holder
within the meaning of either the Act or the Exchange Act against any and all
losses, claims, damages or liabilities, joint or several, to which they or any
of them may become subject under the Act, the Exchange Act or other Federal or
state statutory law or regulation, at common law or otherwise, insofar as such
losses, claims, damages or liabilities (or actions in respect thereof) arise out
of or are based upon any untrue statement or alleged untrue statement of a
material fact contained in the Registration Statement as originally filed or in
any amendment thereof, or in any preliminary Prospectus or the Prospectus, or in
any amendment thereof or supplement thereto, or arise out of or are based upon
the omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
agrees to reimburse each such indemnified party, as incurred, for any legal or
other expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the Issuer, the Company and the Guarantors will not be liable in any case
to the extent that any such loss, claim, damage or liability arises out of or is
based upon any such untrue statement or alleged untrue statement or omission or
alleged omission made therein in reliance upon and in conformity with written
information furnished to the Issuer, the Company and the Guarantors by or on
behalf of any such Holder specifically for inclusion therein. This indemnity
agreement will be in addition to any liability which the Issuer, the Company and
the Guarantors may otherwise have.

                  Each of the Issuer, the Company and the Guarantors also agrees
to indemnify or contribute as provided in Section 6(d) to Losses of each any
underwriter of Securities or New Securities, as the case may be, registered
under a Shelf Registration Statement, their directors, officers, employees or
agents and each Person who controls such underwriter on substantially the same
basis as that of the indemnification of the Initial Purchasers and the selling
Holders provided in this Section 6(a) and shall, if requested by any Holder,
enter into an underwriting agreement reflecting such agreement, as provided in
Section 4(p) hereof.

                  (b)      Each Holder of securities covered by a Registration
Statement (including each Initial Purchaser and, with respect to any Prospectus
delivery as contemplated in Section 4(h) hereof, each Exchanging Dealer)
severally agrees to indemnify and hold harmless each of the Issuer, the Company
and the Guarantors, each of its directors, each of its officers who signs such
Registration Statement and each Person who controls the Issuer, the Company or
any Guarantor within the meaning of either the Act or the Exchange Act, to the
same extent as the foregoing indemnity from each of the Issuer, the Company and
the Guarantors to each such Holder, but only with reference to written
information relating to such Holder furnished to the Issuer, the Company and the
Guarantors by or on behalf of such Holder specifically for inclusion in the
documents referred to in the foregoing indemnity. This indemnity agreement will
be in addition to any liability which any such Holder may otherwise have.

                  (c)      Promptly after receipt by an indemnified party under
this Section 6 or notice of the commencement of any action, such indemnified
party will, if a claim in respect

                                       15

<PAGE>

thereof is to be made against the indemnifying party under this Section, notify
the indemnifying party in writing of the commencement thereof; but the failure
so to notify the indemnifying party (i) will not relieve it from liability under
paragraph (a) or (b) above unless and to the extent it did not otherwise learn
of such action and such failure results in the forfeiture by the indemnifying
party of substantial rights and defenses; and (ii) will not, in any event,
relieve the indemnifying party from any obligations to any indemnified party
other than the indemnification obligation provided in paragraph (a) or (b)
above. The indemnifying party shall be entitled to appoint counsel of the
indemnifying party's choice at the indemnifying party's expense to represent the
indemnified party in any action for which indemnification is sought (in which
case the indemnifying party shall not thereafter be responsible for the fees and
expenses of any separate counsel retained by the indemnified party or parties
except as set forth below); provided, however, that such counsel shall be
satisfactory to the indemnified party. Notwithstanding the indemnifying party's
election to appoint counsel to represent the indemnified party in an action, the
indemnified party shall have the right to employ separate counsel (including
local counsel), and the indemnifying party shall bear the reasonable fees, costs
and expenses of such separate counsel if (i) the use of counsel chosen by the
indemnifying party to represent the indemnified party would present such counsel
with a conflict of interest; (ii) the actual or potential defendants in, or
targets of, any such action include both the indemnified party and the
indemnifying party and the indemnified party shall have reasonably concluded
that there may be legal defenses available to it and/or other indemnified
parties which are different from or additional to those available to the
indemnifying party; (iii) the indemnifying party shall not have employed counsel
satisfactory to the indemnified party to represent the indemnified party within
a reasonable time after notice of the institution of such action; or (iv) the
indemnifying party shall authorize the indemnified party to employ separate
counsel at the expense of the indemnifying party. An indemnifying party will
not, without the prior written consent of the indemnified parties, settle or
compromise or consent to the entry of any judgment with respect to any pending
or threatened claim, action, suit or proceeding in respect of which
indemnification or contribution may be sought hereunder (whether or not the
indemnified parties are actual or potential parties to such claim or action)
unless such settlement, compromise or consent includes an unconditional release
of each indemnified party from all liability arising out of such claim, action,
suit or proceeding.

                  (d)      In the event that the indemnity provided in paragraph
(a) or (b) of this Section is unavailable to or insufficient to hold harmless an
indemnified party for any reason, then each applicable indemnifying party shall
have a joint and several obligation to contribute to the aggregate losses,
claims, damages and liabilities (including legal or other expenses reasonably
incurred in connection with investigating or defending same) (collectively
"Losses") to which such indemnified party may be subject in such proportion as
is appropriate to reflect the relative benefits received by such indemnifying
party, on the one hand, and such indemnified party, on the other hand, from the
Initial Placement and the Registration Statement which resulted in such Losses;
provided, however, that in no case shall any Initial Purchaser or any subsequent
Holder of any Security or New Security be responsible, in the aggregate, for any
amount in excess of the purchase discount or commission applicable to such
Security, or in the case of a New Security, applicable to the Security that was
exchangeable into such New Security, as set forth on the cover page of the Final
Memorandum, nor shall any underwriter be responsible for any amount in excess of
the underwriting discount or commission applicable to the securities purchased
by such underwriter under the Registration Statement which resulted in such
Losses. If the allocation provided by the immediately preceding sentence is
unavailable for

                                       16

<PAGE>

any reason, the indemnifying party and the indemnified party shall contribute in
such proportion as is appropriate to reflect not only such relative benefits but
also the relative fault of such indemnifying party, on the one hand, and such
indemnified party, on the other hand, in connection with the statements or
omissions which resulted in such Losses as well as any other relevant equitable
considerations. Benefits received by each of the Issuer, the Company and the
Guarantors shall be deemed to be equal to the sum of (x) the total net proceeds
from the Initial Placement (before deducting expenses) and (y) the total amount
of additional interest which the Issuer and the Guarantors were not required to
pay as a result of registering the securities covered by the Registration
Statement which resulted in such Losses. Benefits received by the Initial
Purchasers shall be deemed to be equal to the total purchase discounts and
commissions from the Initial Placement, and benefits received by any other
Holders shall be deemed to be equal to the value of receiving Securities or New
Securities, as applicable, registered under the Act. Benefits received by any
underwriter shall be deemed to be equal to the total underwriting discounts and
commissions, as set forth on the cover page of the Prospectus forming a part of
the Registration Statement which resulted in such Losses. Relative fault shall
be determined by reference to, among other things, whether any alleged untrue
statement or omission relates to information provided by the indemnifying party,
on the one hand, or by the indemnified party, on the other hand, the intent of
the parties and their relative knowledge, access to information and opportunity
to correct or prevent such untrue statement or omission. The parties agree that
it would not be just and equitable if contribution were determined by pro rata
allocation (even if the Holders were treated as one entity for such purpose) or
any other method of allocation which does not take account of the equitable
considerations referred to above. Notwithstanding the provisions of this
paragraph (d), no Person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the Act) shall be entitled to contribution from any
Person who was not guilty of such fraudulent misrepresentation. For purposes of
this Section, each Person who controls a Holder within the meaning of either the
Act or the Exchange Act and each director, officer, employee and agent of such
Holder shall have the same rights to contribution as such Holder, and each
Person who controls the Issuer, the Company or any Guarantor within the meaning
of either the Act or the Exchange Act, each officer of the Issuer, the Company
or any Guarantor who shall have signed the Registration Statement and each
director of the Issuer, the Company or any Guarantor shall have the same rights
to contribution as the Issuer, the Company and the Guarantors, subject in each
case to the applicable terms and conditions of this paragraph (d).

                  (e)      The provisions of this Section will remain in full
force and effect, regardless of any investigation made by or on behalf of any
Holder or the Issuer, the Company or any Guarantor or any of the officers,
directors or controlling Persons referred to in this Section hereof, and will
survive the sale by a Holder of securities covered by a Registration Statement.

                  7.       Underwritten Registrations. (a) If any of the
Securities or New Securities, as the case may be, covered by any Shelf
Registration Statement are to be sold in an underwritten offering, the Managing
Underwriters shall be selected by the Majority Holders.

                  (b)      No Person may participate in any underwritten
offering pursuant to any Shelf Registration Statement, unless such Person (i)
agrees to sell such Person's Securities or New Securities, as the case may be,
on the basis reasonably provided in any underwriting arrangements approved by
the Persons entitled hereunder to approve such arrangements; and (ii)

                                       17

<PAGE>

completes and executes all questionnaires, powers of attorney, indemnities,
underwriting agreements and other documents reasonably required under the terms
of such underwriting arrangements.

                  8.       No Inconsistent Agreements. The Issuer, the Company
and the Guarantors have not, as of the date hereof, entered into, nor shall
they, on or after the date hereof, enter into, any agreement with respect to
their securities that is inconsistent with the rights granted to the Holders
herein or otherwise conflicts with the provisions hereof.

                  9.       Amendments and Waivers. The provisions of this
Agreement, including the provisions of this sentence, may not be amended,
qualified, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, unless the Issuer, the Company and the
Guarantors have obtained the written consent of the Majority Holders (or, after
the consummation of any Registered Exchange Offer in accordance with Section 2
hereof, of New Securities); provided that, with respect to any matter that
directly or indirectly affects the rights of any Initial Purchaser hereunder,
the Issuer, the Company and the Guarantors shall obtain the written consent of
each such Initial Purchaser against which such amendment, qualification,
supplement, waiver or consent is to be effective. Notwithstanding the foregoing
(except the foregoing proviso), a waiver or consent to departure from the
provisions hereof with respect to a matter that relates exclusively to the
rights of Holders whose Securities or New Securities, as the case may be, are
being sold pursuant to a Registration Statement and that does not directly or
indirectly affect the rights of other Holders may be given by the Majority
Holders, determined on the basis of Securities or New Securities, as the case
may be, being sold rather than registered under such Registration Statement.

                  10.      Notices. All notices and other communications
provided for or permitted hereunder shall be made in writing by hand-delivery,
first-class mail, telex, telecopier or air courier guaranteeing overnight
delivery:

                  (a)      if to a Holder, at the most current address given by
such holder to the Company in accordance with the provisions of this Section,
which address initially is, with respect to each Holder, the address of such
Holder maintained by the Registrar under the Indenture, with a copy in like
manner to Citigroup Global Markets Inc;

                  (b)      if to you, initially at the respective addresses set
forth in the Purchase Agreement; and

                  (c)      if to the Issuer, the Company or any Guarantor,
initially at its address set forth in the Purchase Agreement.

                  All such notices and communications shall be deemed to have
been duly given when received.

                  The Initial Purchasers or the Issuer, the Company and the
Guarantors by notice to the other parties may designate additional or different
addresses for subsequent notices or communications.

                                       18

<PAGE>

                  11.      Successors. This Agreement shall inure to the benefit
of and be binding upon the successors and assigns of each of the parties,
including, without the need for an express assignment or any consent by the
Issuer, the Company and the Guarantors thereto, subsequent Holders of Securities
and the New Securities. Each of the Issuer, the Company and the Guarantors
hereby agrees to extend the benefits of this Agreement to any Holder of
Securities and the New Securities, and any such Holder may specifically enforce
the provisions of this Agreement as if an original party hereto.

                  12.      Counterparts. This agreement may be in signed
counterparts, each of which shall an original and all of which together shall
constitute one and the same agreement.

                  13.      Headings. The headings used herein are for
convenience only and shall not affect the construction hereof.

                  14.      Applicable Law. This Agreement shall be governed by
and construed in accordance with the laws of the State of New York applicable to
contracts made and to be performed in the State of New York.

                  15.      Severability. In the event that any one of more of
the provisions contained herein, or the application thereof in any
circumstances, is held invalid, illegal or unenforceable in any respect for any
reason, the validity, legality and enforceability of any such provision in every
other respect and of the remaining provisions hereof shall not be in any way
impaired or affected thereby, it being intended that all of the rights and
privileges of the parties shall be enforceable to the fullest extent permitted
by law.

                  16.      Securities Held by the Company or Arch Western, etc.
Whenever the consent or approval of Holders of a specified percentage of
principal amount of Securities or New Securities is required hereunder,
Securities or New Securities, as applicable, held by the Company or Arch
Western, or their Affiliates (other than subsequent Holders of Securities or New
Securities if such subsequent Holders are deemed to be Affiliates solely by
reason of their holdings of such Securities or New Securities) shall not be
counted in determining whether such consent or approval was given by the Holders
of such required percentage.

                                       19

<PAGE>

                  If the foregoing is in accordance with your understanding of
our agreement, please sign and return to us the enclosed duplicate hereof,
whereupon this letter and your acceptance shall represent a building agreement
among the Issuer, the Company and the Guarantors and the several Initial
Purchasers.

                                     Very truly yours,

                                     Arch Western Finance, LLC

                                     By: /s/ JAMES E. FLORCZAK
                                        ----------------------------------------
                                           Name: James E. Florczak
                                           Title: Vice President & Treasurer

                                     Arch Coal, Inc.

                                     By: /s/ ROBERT J. MESSEY
                                        ----------------------------------------
                                           Name: Robert J. Messey
                                           Title: Senior V.P. and C.F.O.

                                     Arch Western Resources, LLC

                                     By: /s/ JAMES E. FLORCZAK
                                        ----------------------------------------
                                           Name: James E. Florczak
                                           Title: Vice President & Treasurer

                                     Thunder Basin Coal Company, L.L.C.

                                     By: /s/ JAMES E. FLORCZAK
                                        ----------------------------------------
                                           Name: James E. Florczak
                                           Title: Vice President & Treasurer

                                     Mountain Coal Company, L.L.C.

                                     By: /s/ JAMES E. FLORCZAK
                                        ----------------------------------------
                                           Name: James E. Florczak
                                           Title: Vice President & Treasurer

                                     Arch of Wyoming, LLC

                                     By: /s/ JAMES E. FLORCZAK
                                        ----------------------------------------
                                           Name: James E. Florczak
                                           Title: Vice President & Treasurer

<PAGE>

The foregoing Agreement is hereby confirmed and
accepted as of the date first above written.

Citigroup Global Markets Inc.
J.P. Morgan Securities Inc.
Morgan Stanley & Co. Incorporated

By:  Citigroup Global Markets Inc.

By: /s/ ASHOK NAYYAR
   ----------------------------------------
     Name: Ashok Nayyar
     Title: Managing Director

For themselves and the other several
Initial Purchasers named in Schedule I
of the Purchase Agreement.

<PAGE>

                                                                         ANNEX A

                  Each Broker-Dealer that receives New Securities for its own
account pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such New Securities. The Letter of
Transmittal states that by so acknowledging and by delivering a prospectus, a
Broker-Dealer will not be deemed to admit that it is an "underwriter: within the
meaning of the Securities Act. This Prospectus, as it may be amended or
supplemented from time to time, may be used by a Broker-Dealer in connection
with resales of New Securities received in exchange for Securities where such
Securities were acquired by such Broker-Dealer as a result of market-making
activities or other trading activities. The Issuer and the Guarantors have
agreed that, starting on the Expiration Date (as defined herein) and ending on
the close of business one year after the Expiration Date, they will make this
Prospectus available to any Broker-Dealer for use in connection with any such
resale. See "Plan of Distribution".

<PAGE>

                                                                         ANNEX B

                  Each Broker-Dealer that receives New Securities for its own
account in exchange for Securities, where such Securities were acquired by such
Broker-Dealer as a result of market-making activities or other trading
activities, must acknowledge that it will deliver a prospectus in connection
with any resale of such New Securities. See "Plan of Distribution".

<PAGE>

                                                                         ANNEX C

                              PLAN OF DISTRIBUTION

                  Each Broker-Dealer that receives New Securities for its own
account pursuant to the Exchange Offer must acknowledge that it will deliver a
prospectus in connection with any resale of such New Securities. This
Prospectus, as it may be amended or supplemented from time to time, may be used
by a Broker-Dealer in connection with resales of New Securities received in
exchange for Securities where such Securities were acquired as a result of
market-making activities or other trading activities. The Issuer and the
Guarantors have agreed that, starting on the Expiration Date and ending on the
close of business 180 days after the Expiration Date, they will make this
Prospectus, as amended or supplemented, available to any Broker-Dealer for use
in connection with any such resale. In addition, until __________, 20___,
dealers effecting transactions in the New Securities may be required to deliver
a prospectus.

                  The Issuer and the Guarantors will not receive any proceeds
from any sale of New Securities by brokers-dealers. New Securities received by
Broker-Dealers for their own account pursuant to the Exchange Offer may be sold
from time to time in one or more transactions in the over-the-counter market, in
negotiated transactions, through the writing of options on the New Securities or
a combination of such methods of resale, at market prices prevailing at the time
of resale, at prices related to such prevailing market prices or negotiated
prices. Any such resale may be made directly to purchasers or to or through
brokers or dealers who may receive compensation in the form of commissions or
concessions from any such Broker-Dealer and/or the purchasers of any such New
Securities. Any Broker-Dealer that resales New Securities that were received by
it for its own account pursuant to the Exchange Offer and any broker or dealer
that participates in a distribution of such New Securities may be deemed to be
an "underwriter" within the meaning of the Securities Act and any profit of any
such resale of New Securities and any commissions or concessions received by any
such Persons may be deemed to be underwriting compensation under the Securities
Act. The Letter of Transmittal states that by acknowledging that it will deliver
and by delivering a prospectus, a Broker-Dealer will not be deemed to admit that
it is an "underwriter" within the meaning of the Securities Act.

                  For a period of 180 days after the Expiration Date, the Issuer
and the Guarantors will promptly send additional copies of this Prospectus and
any amendment or supplement to this Prospectus to any Broker-Dealer that
requests such documents in the Letter of Transmittal. The Issuer and the
Guarantors have agreed to pay all expenses incident to the Exchange Offer
(including the expenses of one counsel for the holder of the Securities) other
than commissions or concessions of any brokers or dealers and will indemnify the
holders of the Securities (including any Broker-Dealers) against certain
liabilities, including liabilities under the Securities Act.

<PAGE>

                                                                         ANNEX D

Rider A

                  CHECK HERE IF YOU ARE A BROKER-DEALER AND WISH TO RECEIVE 10
                  ADDITIONAL COPIES OF THE PROSPECTUS AND 10 COPIES OF ANY
                  AMENDMENTS OR SUPPLEMENTS THERETO.

                  Name:             _______________________________
                  Address:          _______________________________
                                    _______________________________

Rider B

If the undersigned is not a Broker-Dealer, the undersigned represents that it
acquired the New Securities in the ordinary course of its business, it is not
engaged in, and does not intend to engage in, a distribution of New Securities
and it has not arrangements or understandings with any Person to participate in
a distribution of the New Securities. If the undersigned is a Broker-Dealer that
will receive New Securities for its own account in exchange for Securities, it
represents that the Securities to be exchange for New Securities were acquired
by it as a result of market-making activities or other trading activities and
acknowledges that it will deliver a prospectus in connection with any resale of
such New Securities; however, by so acknowledging and by delivering a
prospectus, the undersigned will not be deemed to admit that it is an
"underwriter" within the meaning of the Securities Act.