UTAH STATE LEASE FOR COAL ML 51191-OBA COTTONWOOD COMPETITIVE LEASING UNIT PARCEL #1 (REVERSIONARY TRACT)

Exhibit 10.21

GRANT: PL 105 Multiple

UTAH STATE LEASE FOR COAL
ML 51191-OBA

COTTONWOOD COMPETITIVE LEASING UNIT
PARCEL #1 (REVERSIONARY TRACT)

     THIS COAL MINING LEASE AND AGREEMENT (the “Lease”) is entered into and executed in duplicate as of January 18, 2008 (the “Effective Date”) by and between the STATE OF UTAH, acting by and through the SCHOOL AND INSTITUTIONAL TRUST LANDS ADMINISTRATION, 675 East 500 South, Suite 500, Salt Lake City, Utah 84102 (“Lessor”), and

Ark Land Company
One CityPlace Drive — Suite 300
St. Louis, MO 63141

having a business address as shown above (“Lessee”).

WITNESSETH:

     That the State of Utah, as Lessor, in consideration of the rentals, royalties, and other financial consideration paid or required to be paid by Lessee, and the covenants of Lessee set forth below, does hereby GRANT AND LEASE to Lessee the exclusive right and privilege to explore for, drill for, mine, remove, transport, convey, cross-haul, commingle, and sell the coal located within the boundaries of the following-described tract of land located in Emery County, State of Utah:

PARCEL 1 (Cottonwood Coal Exchange Tract — Partial)

Township 17 South Range, 6 East, SLB&M