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                                                                   Exhibit 10.31

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

         This ASSIGNMENT AND ASSUMPTION AGREEMENT (this "Agreement"), dated as
of April 1, 2003, is entered into by and among Hopkins County Coal, LLC, a
Delaware limited liability company ("Assignor"), and Warrior Coal, LLC, a
Delaware limited liability company ("Assignee"), and SynFuel Solutions Operating
LLC, a Delaware limited liability company ("SSO"). Assignor, Assignee and SSO
may be referred to herein individually as a "Party", and collectively as the
"Parties."

Recitals:

         A.       Assignor and SSO are parties to that certain Coal Feedstock
Supply Agreement dated October 26, 2001, as previously and further amended (the
"Coal Feedstock Supply Agreement"), and all of the Coal Purchase Orders entered
into pursuant to the Coal Feedstock Supply Agreement (collectively with the Coal
Feedstock Supply Agreement, the "Contracts"), pursuant to which Assignor agreed
to sell to SSO, and SSO agreed to purchase from Assignor, certain quantities of
Coal.

         B.       Assignor desires to assign to Assignee, and Assignee desires
to accept and assume from Assignor, all rights and obligations of Assignor
arising under the Contracts from and after the Effective Date.

         C.       Capitalized terms not otherwise defined in this Agreement are
used herein as such terms are defined in the Coal Feedstock Supply Agreement.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Assignor and Assignee hereby agree
as follows:

         1.       Assignment. Assignor hereby assigns to Assignee, its
successors and assigns, all of Assignor's rights, titles and interests under the
Contracts and all obligations of Assignor arising therefrom and relating to
periods from and after the Effective Date.

         2.       Acceptance and Assumption. Assignee hereby accepts the
assignment of all of Assignor's rights, titles and interests under the
Contracts, agrees to be bound by all of the terms, covenants and conditions
thereof, and hereby assumes all of Assignor's obligations arising under the
Contracts and relating to periods from and after the Effective Date.

         3.       Effectiveness. This Agreement, and the assignment provided for
herein, will have effect from and after, and not before, the date on which SSO
notifies Assignor and Assignee in writing that the conditions precedent to the
commencement of the relocation of the Coal Synfuel Plant to the Warrior Site
that are set forth in paragraph 3 of the Letter Agreement dated February 1, 2003
among Assignor, Assignee and SSO have been satisfied or waived by SSO (the
"Effective Date").

         4.       Consent. SSO hereby consents to the foregoing assignment.

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         5.       Warranties.

         (a)      Each Party hereby represents and warrants to the others that
the execution, delivery and performance hereof by it are within its corporate or
other organizational powers, and have been duly authorized by all necessary
corporate or other organizational action and that this Agreement constitutes its
legal, valid and binding obligation, enforceable against it in accordance with
its terms (except as such enforcement may be limited by bankruptcy, insolvency,
reorganization, moratorium and similar laws of general applicability relating to
or affecting creditors' rights and to general equity principles).

         (b)      Each Party hereby represents and warrants to the others that
neither the execution, delivery and performance of this Agreement, nor the sale,
transfer, and assignment of the rights, titles and interests under the Contracts
and all obligations of Assignor arising from the Contracts pursuant to this
Agreement, will require any consent, approval, authorization or permit of, or
filing with or notification to, any person or governmental or regulatory
authority.

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         IN WITNESS WHEREOF, each party has caused this Agreement to be executed
by its duly authorized representative as of the date first set forth above:

                        ASSIGNOR:

                        HOPKINS COUNTY COAL, LLC

                        By: /s/ Gary J. Rathburn
                             -------------------------------------------------
                        Name: Gary J. Rathburn
                        Title: Senior Vice President - Marketing

                        ASSIGNEE:

                        WARRIOR COAL, LLC

                        By: /s/ Gary J. Rathburn
                            -------------------------------------------------
                        Name: Gary J. Rathburn
                        Title: Senior Vice President - Marketing

                        SYNFUEL SOLUTIONS OPERATING LLC

                         By: SynFuel Solutions LLC,
                             its Managing Member

                             By: SynFuel Solutions Holdings LLC,
                                 its Managing Member

                                 By: /s/ Joseph E. Slamm, III
                                     ----------------------------------------
                                 Name: Joseph E. Slamm, III
                                 Title: Vice President

              Signature Page to Assignment and Assumption Agreement