<PAGE>
                                                                    EXHIBIT 10.5



================================================================================

                                     FORM OF

                                OMNIBUS AGREEMENT

                                      among

                                 ARCH COAL, INC.

                                ARK LAND COMPANY

                WESTERN POCAHONTAS PROPERTIES LIMITED PARTNERSHIP

                  GREAT NORTHERN PROPERTIES LIMITED PARTNERSHIP

                           NEW GAULEY COAL CORPORATION

                          ROBERTSON COAL MANAGEMENT LLC

                        GP NATURAL RESOURCE PARTNERS LLC

                                   NRP (GP) LP

                         NATURAL RESOURCE PARTNERS L.P.

                                       and

                               NRP (OPERATING) LLC



================================================================================



<PAGE>


                                OMNIBUS AGREEMENT


         THIS OMNIBUS AGREEMENT ("Agreement") is entered into on, and effective
as of, the Closing Date (as defined herein) among Arch Coal, Inc., a Delaware
corporation ("Arch"), Ark Land Company, a Delaware corporation ("Ark"), Western
Pocahontas Properties Limited Partnership, a Delaware limited partnership
("WPP"), Great Northern Properties Limited Partnership, a Delaware limited
partnership ("GNP"), New Gauley Coal Corporation, a West Virginia corporation
("NGCC" and, together with WPP and GNP, the "WPP Group"), Robertson Coal
Management LLC, a Delaware limited liability company, GP Natural Resource
Partners LLC (the "LLC GP"), NRP (GP) LP, a Delaware limited partnership
(including any permitted successors and assigns under the Partnership Agreement
(as defined herein), the "General Partner"), GP Natural Resource Partners LLC
(the "LLC GP"), Natural Resource Partners L.P., a Delaware limited partnership
(the "Partnership") and NRP (Operating) LLC, a Delaware limited liability
company ("OLLC"). The above-named entities are sometimes referred to in this
Agreement each as a "Party" and collectively as the "Parties."

                                    RECITALS:

         1. The Parties desire by their execution of this Agreement to evidence
their understanding, as more fully set forth in Article II, with respect to
those business opportunities that the Sponsors (as defined herein) will not
engage in for so long as the Partnership is an Affiliate (as defined herein) of
the Sponsors unless the Partnership has declined to engage in any such business
opportunity for its own account.

         2. The Parties desire by their execution of this Agreement to evidence
their understanding, as more fully set forth in Article III, with respect to
certain indemnification obligations of the Sponsors in favor of the Partnership
Group (as defined herein).

         In consideration of the premises and the covenants, conditions and
agreements contained herein, and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Parties hereto
hereby agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

                  1.1 DEFINITIONS.

                           (a) As used in this Agreement, the following terms
         shall have the respective meanings set forth below:

                  "Affiliate" is defined in the Partnership Agreement.

                  "Assets" means all assets conveyed, contributed, or otherwise
         transferred by the Sponsors to the Partnership Group prior to or on the
         Closing Date.

                  "Closing Date" means the date of the closing of the
         Partnership's initial public offering of Common Units.








                               Schedule VIII - 1
<PAGE>

                  "Common Units" is defined in the Partnership Agreement.

                  "Conflicts Committee" is defined in the Partnership Agreement.

                  "control" means the possession, directly or indirectly, of the
         power to direct or cause the direction of the management and policies
         of a Person, whether through ownership of voting securities, by
         contract, or otherwise.

                  "Covered Environmental Losses" is defined in Section 3.1.

                  "Environmental Laws" means all federal, state, and local laws,
         statutes, rules, regulations, orders, and ordinances, now or hereafter
         in effect, relating to protection of human health and the environment
         including, without limitation, the federal Comprehensive Environmental
         Response, Compensation, and Liability Act, the Superfund Amendments
         Reauthorization Act, the Surface Mining Control and Reclamation Act,
         the Mine Health and Safety Acts of 1969 and 1977, the Resource
         Conservation and Recovery Act, the Clean Air Act, the Clean Water Act,
         the Federal Water Pollution Control Act, the Toxic Substances Control
         Act, the Safe Drinking Water Act, the Emergency Planning and Community
         Right-to-Know Act, and other environmental conservation and protection
         laws, each as amended from time to time.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
         amended.

                  "Group Member" is defined in the Partnership Agreement.

                  "Limited Partner" is defined in the Partnership Agreement.

                  "Majority Sponsor" means the WPP Group and any other Person
         controlled by Corbin J. Robertson, Jr.

                  "Minority Sponsor" means Arch.

                  "Offer" is defined in Section 2.4(a).

                  "Partnership Agreement" means the First Amended and Restated
         Agreement of Limited Partnership of Natural Resource Partners L.P.,
         dated as of the Closing Date, as such agreement is in effect on the
         Closing Date, to which reference is hereby made for all purposes of
         this Agreement. No amendment or modification to the Partnership
         Agreement subsequent to the Closing Date shall be given effect for the
         purposes of this Agreement unless consented to by each of the Parties
         to this Agreement.

                  "Partnership Group" is defined in the Partnership Agreement

                  "Person" is defined in the Partnership Agreement

                  "Restricted Business" is defined in Section 2.1.

                  "Second Offer" is defined in Section 2.4(c).






                                       2
<PAGE>

                  "Sponsor" means any of the Majority Sponsor or the Minority
         Sponsor, and "Sponsors" means both the Majority Sponsor and the
         Minority Sponsor.

                  "Subsidiary" is defined in the Partnership Agreement.

                  "Unit" is defined in the Partnership Agreement.

                                   ARTICLE II
                             BUSINESS OPPORTUNITIES

         2.1 RESTRICTED ACTIVITIES

                  (a) Restricted Businesses. For so long as a Sponsor
participates in the control of the General Partner, and except as permitted by
Section 2.2, the Sponsors and their Affiliates shall be prohibited from owning,
operating or investing in any business having assets engaged in the following
activities (each, a "Restricted Business"):

                           (i) owning or entering into leases with a party other
than an Affiliate of a Sponsor of any fee coal reserves within the United States
owned by a Sponsor or its Affiliate; or

                           (ii) owning or entering into subleases with a party
other than an Affiliate of a Sponsor of any coal reserves within the United
States controlled by a paid-up lease owned by a Sponsor or its Affiliate.

                  (b) Restrictions on Investments in New Entities. For so long
as a Sponsor participates in the control of the General Partner, and except as
permitted by Section 2.2 and subject to Sections 2.3 and 2.4, the Sponsors and
their Affiliates shall be prohibited from the following actions:

                           (i) The Majority Sponsor and its Affiliates may not,
through one or more transactions, form or purchase (1) a general partner
interest in any partnership (publicly traded or private) that principally
engages in a Restricted Business, (2) a managing member interest in any limited
liability company (publicly traded or private) that principally engages in a
Restricted Business or (3) a controlling interest in any corporation (publicly
traded or private) that principally engages in a Restricted Business; provided,
however, that the Majority Sponsor may form or purchase a general partner
interest in any private partnership, a managing member interest in any private
limited liability company or a controlling interest in any private corporation,
each principally engaging in a Restricted Business, subject to Sections 2.3 and
2.4.

                           (ii) The Minority Sponsor and its Affiliates may not,
through one or more transactions, form or purchase (1) a general partner
interest in any partnership (publicly traded or private) that principally
engages in a Restricted Business, (2) a managing member interest in any limited
liability company (publicly traded or private) that principally engages in a
Restricted Business or (3) a controlling interest in any corporation (publicly
traded or private) that principally engages in a Restricted Business; provided,
however, that the Minority Sponsor may form or purchase a general





                                       3
<PAGE>

partner interest in any partnership (publicly traded or private), a managing
member interest in any limited liability company (publicly traded or private) or
a controlling interest in any corporation (publicly traded or private), each
principally engaging in a Restricted Business, so long as (i) the Minority
Sponsor sells such general partner interest, managing member interest or
controlling interest to the Partnership or a third party within six months of
the date of the acquisition by the Minority Sponsor or (ii) the General Partner
(with the concurrence of the Conflicts Committee) agrees that the Restricted
Business will be subject to Section 2.4 of this Agreement without further
reference to this paragraph. If, at any time after six months from the date of
such formation or acquisition by the Minority Sponsor, the Minority Sponsor
continues to own such interest despite a good faith, reasonable attempt to
divest such interest, it may seek an extension from the Conflicts Committee for
such time as is reasonably necessary to divest such interest. The Conflicts
Committee, in its discretion, may either (i) grant an extension to the Minority
Sponsor to complete the divestiture of such interest or (ii) subject the
interest to Section 2.4.

         2.2 PERMITTED EXCEPTIONS.

         Notwithstanding any provision of Section 2.1 to the contrary, and
subject to Section 2.3 in the case of assets retained by a Sponsor pursuant to
Section 2.2(a) or Section 2.2(b)(i), any Sponsor or its Affiliate may engage in
the following activities under the following circumstances:

                  (a) owning, operating or investing in any Restricted Business
that is retained by a Sponsor or its Affiliate as of the Closing Date; provided,
however that if the Restricted Business has a fair market value (as determined
in good faith by the board of directors, or other governing body, of the Sponsor
that owns, operates or invests in the Restricted Business) greater than $10
million, the Sponsor must offer the Restricted Business to the Partnership Group
in accordance with Section 2.4;

                  (b) owning, operating or investing in a Restricted Business
that is acquired by a Sponsor or its Affiliate after the Closing Date if:

                           (i) the fair market value of the Restricted Business
(as determined in good faith by the board of directors, or other governing body,
of the Sponsor that will own, operate or invest in the Restricted Business) is
equal to or less than $10 million at the time of such acquisition by such
Sponsor or its Affiliate; provided, however, that if the fair market value of
the Restricted Business subsequently exceeds $10 million, the Sponsor must offer
the Restricted Business to the Partnership Group in accordance with Section 2.4.

                           (ii) in the case of an acquisition of a Restricted
Business with a fair market value (as determined in good faith by the board of
directors, or other governing body, of the Sponsor that will own, operate or
invest in the Restricted Business) greater than $10 million at the time of such
acquisition by the Sponsor, the Partnership Group has been offered the
opportunity to purchase the Restricted Business





                                       4
<PAGE>

in accordance with Section 2.4 and the Partnership Group (with the concurrence
of the Conflicts Committee) has elected not to purchase the Restricted Business.

                           (iii) the investment in the Restricted Business is
held by means of an equity interest in the entity that owns the Restricted
Business and such equity interest does not constitute control of the Restricted
Business.

         2.3 LIMITATION ON ACQUISITIONS BY THE MAJORITY SPONSOR.

                  (a) Notwithstanding Section 2.2, the total fair market value
(as determined in good faith by the board of directors, or other governing body,
of the Majority Sponsor) of all Restricted Businesses owned, operated or
invested in by the Majority Sponsor (other than those owned or operated by the
Majority Sponsor as of the Closing Date) may not exceed $75 million. For
purposes of this Section 2.3, the fair market value of any entity owning the
Restricted Businesses purchased by the Majority Sponsor shall be determined
based on the fair market value of the entity as a whole, without regard for any
lesser ownership interest therein to be acquired.

         2.4 PROCEDURES.

                  (a) If a Sponsor acquires a Restricted Business described in
Section 2.2(b)(ii) and such Restricted Business constitutes greater than 50% of
the aggregate value of the entire acquisition, then not later than six months
after the consummation of the acquisition by such Sponsor of the Restricted
Business, the Sponsor shall (i) notify the General Partner in writing of such
acquisition, (ii) deliver to the General Partner all information prepared by or
on behalf of the Sponsor relating to such purchase and (iii) offer the
Partnership Group the opportunity to purchase such Restricted Business in
accordance with this Section 2.4 (the "Offer"). The Offer shall set forth the
terms relating to the purchase of the Restricted Business. As soon as
practicable, but in any event within 60 days after receipt of such written
notification, the General Partner shall notify the Sponsor in writing that
either (i) the General Partner has elected, with the approval of the Conflicts
Committee, not to cause a Group Member to purchase the Restricted Business, in
which event the Sponsor may continue to own, operate or invest in such
Restricted Business or (ii) the General Partner has elected to cause a Group
Member to purchase the Restricted Business, in which event the procedures
outlined in this Section 2.4 shall apply. For purposes of this Section 2.4, a
"Restricted Business" excludes a general partner interest or a managing member
interest, which interests are addressed in Section 2.1.

                  (b) If the Sponsor and the General Partner (with the
concurrence of the Conflicts Committee) are able to agree on the fair market
value of the Restricted Business that is subject to the Offer and the other
terms of the Offer, a Group Member shall purchase the Restricted Business for
the agreed upon fair market value as soon as commercially practicable after such
agreement has been reached. The purchase agreement for the Restricted Business
will provide for the purchase price to be paid, at the option of the Sponsor, in
cash, Units, or an interest-bearing promissory note (the





                                       5
<PAGE>

interest rate and other terms of which shall be mutually agreed upon by the
Sponsor and the General Partner) or any combination thereof.

                  (c) If the Sponsor and the General Partner are unable to agree
on the fair market value of the Restricted Business that is subject to the Offer
or the other terms of the Offer within 60 days after receipt by the General
Partner of the Offer, then the Sponsor may not, for a period of two years
following the date of the Offer, sell the Restricted Business to a third party
for less than the price set forth in the Offer or on more favorable terms than
the terms set forth in the Offer; provided, however, that if during such
two-year period, a change occurs in the Restricted Business that, in the opinion
of the relevant Sponsor, affects the fair market value of such Restricted
Business by more than 10% and the fair market value is still greater than $10
million, the Sponsor shall be obligated to re-offer such Restricted Business to
the Partnership Group at the new fair market value (as determined in good faith
by the board of directors, or other governing body, of the Sponsor that owns the
Restricted Business) and the process described below with respect to the Second
Offer shall commence. If, at the end of the two-year period, the Sponsor has not
sold the Restricted Business to a third party and the Restricted Business still
has a fair market value (as determined in good faith by the board of directors,
or other governing body, of the Sponsor that owns the Restricted Business)
greater than $10 million, the Sponsor will again offer the Partnership Group the
opportunity to purchase such Restricted Business in accordance with this Section
2.4 (the "Second Offer"). The Second Offer shall set forth the terms relating to
the purchase of the Restricted Business. As soon as practicable, but in any
event within 60 days after receipt of the Second Offer, the General Partner
shall notify the Sponsor in writing that either (i) the General Partner has
elected, with the approval of the Conflicts Committee, not to cause a Group
Member to purchase the Restricted Business, in which event the Sponsor may
continue to own such Restricted Business, or (ii) the General Partner has
elected to cause a Group Member to purchase the Restricted Business, in which
event a Group Member shall purchase the Restricted Business for the agreed upon
fair market value as soon as commercially practicable after such agreement has
been reached. The purchase agreement for the Restricted Business will provide
for the purchase price to be paid, at the option of the Sponsor, in cash, Units,
or an interest-bearing promissory note (the interest rate and other terms of
which shall be mutually agreed upon by the Sponsor and the General Partner) or
any combination thereof.

         2.5 SCOPE OF PROHIBITION. Except as provided in this Article II and the
Partnership Agreement, each Sponsor and its Affiliates shall be free to engage
in any business activity, including those that may be in direct competition with
any Group Member.


         2.6 ENFORCEMENT. The Sponsors agree and acknowledge that the
Partnership Group does not have an adequate remedy at law for the breach by a
Sponsor of the covenants and agreements set forth in this Article II, and that
any breach by a Sponsor of the covenants and agreements set forth in this
Article II would result in irreparable injury to the Partnership Group. The
Sponsors each further agree and acknowledge that any Group Member may, in
addition to the other remedies which may be available to the Partnership Group,
file a suit in equity to enjoin






                                       6
<PAGE>

a Sponsor Entity from such breach, and consent to the issuance of injunctive
relief under this Agreement.


                                   ARTICLE III
                                 INDEMNIFICATION

         3.1 INDEMNIFICATION BY THE SPONSORS.

                  (a) Subject to Section 3.2, the Sponsors, jointly and
severally, shall indemnify, defend and hold harmless the Partnership Group for a
period of three years after the Closing Date from and against all Covered
Environmental Losses, defined as follows: any event or condition associated with
ownership or operation of the Assets including, without limitation, (A) the cost
and expense of any investigation, assessment, evaluation, monitoring,
containment, cleanup, repair, restoration, remediation, or other corrective
action required or necessary under Environmental Laws, (B) the cost or expense
of the preparation and implementation of any closure, remedial, corrective
action, or other plans required or necessary under Environmental Laws, (C) the
cost and expense for any environmental or toxic tort pre-trial, trial, or
appellate legal or litigation support work and (D) any violation or correction
of violation of Environmental Laws associated with the Assets; but only to the
extent that such violation complained of under this section or such events or
conditions included under this section occurred before the Closing Date
(collectively, "Covered Environmental Losses").

                  (b) The Sponsors, jointly and severally, shall indemnify,
defend and hold harmless the Partnership Group from and against all federal,
state and local income tax liabilities attributable to the operation of the
Assets prior to the Closing Date, including any such income tax liabilities of
the Sponsors and their Affiliates that may result from the consummation of the
formation transactions for the Partnership Group.

         3.2 LIMITATIONS REGARDING ENVIRONMENTAL INDEMNIFICATION

                  (a) The Sponsors shall have no indemnification obligation
under Section 3.1 for (i) claims made after the third anniversary of the Closing
Date or (ii) claims made as a result of additions to or modifications of the
Environmental Laws made after the Closing Date.

                  (b) The aggregate liability of the Sponsors in respect of all
Covered Environmental Claims under Section 3.1(a) shall not exceed $10.0
million.

         3.3 INDEMNIFICATION PROCEDURES.

                  (a) The Partnership Group agrees that within a reasonable
period of time after it becomes aware of facts giving rise to a claim for
indemnification under this Article III, it will provide notice thereof in
writing to the Sponsors, specifying the nature of and specific basis for such
claim.





                                       7
<PAGE>

                  (b) The Sponsors shall have the right to control all aspects
of the defense of (and any counterclaims with respect to) any claims brought
against the Partnership Group that are covered by the indemnification under this
Article III, including, without limitation, the selection of counsel,
determination of whether to appeal any decision of any court and the settling of
any such matter or any issues relating thereto; provided, however, that no such
settlement shall be entered into without the consent of the Partnership Group
unless it includes a full release of the Partnership Group from such matter or
issues, as the case may be.

                  (c) The Partnership Group agrees to cooperate fully with the
Sponsors, with respect to all aspects of the defense of any claim covered by the
indemnification under this Article III, including, without limitation, the
prompt furnishing to the Sponsors of any correspondence or other notice relating
thereto that the Partnership Group may receive, permitting the name of the
Partnership Group to be utilized in connection with such defense, the making
available to the Sponsors of any files, records or other information of the
Partnership Group that the Sponsors consider relevant to such defense and the
making available to the Sponsors of any employees of the Partnership Group;
provided, however, that in connection therewith the Sponsors agree to use
reasonable efforts to minimize the impact thereof on the operations of the
Partnership Group and further agree to maintain the confidentiality of all
files, records, and other information furnished by the Partnership Group
pursuant to this Section 3.3. In no event shall the obligation of the
Partnership Group to cooperate with the Sponsors as set forth in the immediately
preceding sentence be construed as imposing upon the Partnership Group an
obligation to hire and pay for counsel in connection with the defense of any
claims covered by the indemnification set forth in this Article III; provided,
however, that the Partnership Group may, at its own option, cost and expense,
hire and pay for counsel in connection with any such defense. The Sponsors agree
to keep any such counsel hired by the Partnership Group informed as to the
status of any such defense, but the Sponsors shall have the right to retain sole
control over such defense.

                  (d) In determining the amount of any loss, cost, damage or
expense for which the Partnership Group is entitled to indemnification under
this Agreement, the gross amount of the indemnification will be reduced by (i)
any insurance proceeds realized by the Partnership Group, and such correlative
insurance benefit shall be net of any incremental insurance premium that becomes
due and payable by the Partnership Group as a result of such claim and (ii) all
amounts recovered by the Partnership Group under contractual indemnities from
third Persons.

                  (e) The date on which notification of a claim for
indemnification is received by the Sponsors shall determine whether such claim
is timely made under Section 3.2.





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<PAGE>

                                   ARTICLE IV
                                  MISCELLANEOUS

         4.1 CHOICE OF LAW; SUBMISSION TO JURISDICTION. This Agreement shall be
subject to and governed by the laws of the State of Texas, excluding any
conflicts-of-law rule or principle that might refer the construction or
interpretation of this Agreement to the laws of another state. Each Party hereby
submits to the jurisdiction of the state and federal courts in the State of
Texas and to venue in Houston, Texas.

         4.2 NOTICE. All notices or requests or consents provided for by, or
permitted to be given pursuant to, this Agreement must be in writing and must be
given by depositing same in the United States mail, addressed to the Person to
be notified, postpaid, and registered or certified with return receipt requested
or by delivering such notice in person or by telecopier or telegram to such
Party. Notice given by personal delivery or mail shall be effective upon actual
receipt. Notice given by telegram or telecopier shall be effective upon actual
receipt if received during the recipient's normal business hours or at the
beginning of the recipient's next business day after receipt if not received
during the recipient's normal business hours. All notices to be sent to a Party
pursuant to this Agreement shall be sent to or made at the address set forth
below such Party's signature to this Agreement or at such other address as such
Party may stipulate to the other Parties in the manner provided in this Section
4.2.

                  if to Arch or Ark:

                      Arch Coal, Inc.
                      Attention: General Counsel
                      CityPlace One, Suite 300
                      St. Louis, MO 63141
                      Telecopy:  (314) 994-2878

                  if to WPP or NGCC:

                      Western Pocahontas Properties Limited Partnership or
                      New Gauley Coal Corporation
                      Attention: [            ]
                      P.O. Box 2827
                      1035 Third Avenue, Suite 300
                      Huntington, WV 25727
                      Telecopy: (304) 522-5401

                  if to GNP:

                      Great Northern Properties Limited Partnership
                      Attention: [            ]
                      601 Jefferson, Suite 3600
                      Telecopy:  (713) 751-7510





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<PAGE>

                  if to Robertson Coal Management LLC

                      Robertson Coal Management LLC
                      601 Jefferson Street, Suite 3600
                      Houston, TX 77002
                      Telecopy:  (713) 751-7510

                  if to any Group Member

                      NRP (GP) LP
                      Attention: [           ]
                      601 Jefferson, Suite 3600
                      Telecopy:  (713) 751-7510

         4.3 ENTIRE AGREEMENT. This Agreement constitutes the entire agreement
of the Parties relating to the matters contained herein, superseding all prior
contracts or agreements, whether oral or written, relating to the matters
contained herein.

         4.4 TERMINATION. This Agreement will terminate with respect to any
Sponsor upon the sale or other disposition of all of such Sponsor's membership
interest in LLC GP and limited partnership interest in the General Partner and
the termination of its right to nominate and elect the directors of LLC GP.

         4.5 AMENDMENT OR MODIFICATION. This Agreement may be amended or
modified from time to time after the Closing Date only by the written agreement
of all the Parties hereto; provided, however, that the Partnership may not,
without the prior approval of the Conflicts Committee, agree to any amendment or
modification of this Agreement that, in the reasonable discretion of the General
Partner, will adversely affect the holders of Common Units. Each such instrument
shall be reduced to writing and shall be designated on its face an "Amendment"
or an "Addendum" to this Agreement.

         4.6 ASSIGNMENT. No Party shall have the right to assign its rights or
obligations under this Agreement without the consent of the other Parties
hereto.

         4.7 COUNTERPARTS. This Agreement may be executed in any number of
counterparts with the same effect as if all signatory parties had signed the
same document. All counterparts shall be construed together and shall constitute
one and the same instrument.

         4.8 SEVERABILITY. If any provision of this Agreement shall be held
invalid or unenforceable by a court or regulatory body of competent
jurisdiction, the remainder of this Agreement shall remain in full force and
effect.

         4.9 FURTHER ASSURANCES. In connection with this Agreement and all
transactions contemplated by this Agreement, each signatory party hereto agrees
to execute and deliver such additional documents and instruments and to perform
such additional acts as may be necessary or appropriate to effectuate, carry out
and perform all of the terms, provisions and conditions of this Agreement and
all such transactions.





                                       10
<PAGE>

         4.10 RIGHTS OF LIMITED PARTNERS. The provisions of this Agreement are
enforceable solely by the Parties to this Agreement, and no Limited Partner of
the Partnership shall have the right, separate and apart from the Partnership,
to enforce any provision of this Agreement or to compel any Party to this
Agreement to comply with the terms of this Agreement.




                                       11
<PAGE>


         IN WITNESS WHEREOF, the Parties have executed this Agreement on, and
effective as of, the Closing Date.


                         ARCH COAL, INC.


                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------

                         ARK LAND COMPANY

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------

                         WESTERN POCAHONTAS PROPERTIES LIMITED PARTNERSHIP

                         By:      Western Pocahontas Corporation,
                                  Its General Partner

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------


                         GREAT NORTHERN PROPERTIES LIMITED PARTNERSHIP

                         By:      GNP Management Corporation,
                                  Its General Partner

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------


                         NEW GAULEY COAL CORPORATION

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------




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<PAGE>


                         ROBERTSON COAL MANAGEMENT LLC

                         By:    Corbin J. Robertson, Jr.
                                Its Managing Member

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------


                         GP NATURAL RESOURCE PARTNERS LLC

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------


                         NRP (GP) LP

                         By:    GP Natural Resource Partners LLC,
                                Its General Partner

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------


                         NATURAL RESOURCE PARTNERS L.P.

                         By:    NRP (GP) LP,
                                Its General Partner

                         By:    GP Natural Resource Partners LLC,
                                Its General Partner

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------






                                       13
<PAGE>

                         NRP (OPERATING) LLC

                         By:    Natural Resource Partners L.P.,
                                Its Managing Member

                         By:    NRP (GP) LP
                                Its General Partner

                         By:    GP Natural Resource Partners LLC
                                Its General Partner

                                By:
                                   -------------------------------------------
                                Name:
                                     -----------------------------------------
                                Title:
                                      ----------------------------------------



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