Logical Mining Unit (LMU)
An area of land in which the recoverable coal reserves can be developed in an efficient, economical and orderly manner as a unit with due regard to conservation of coal reserves and other resources. An LMU may consist of one or more federal coal leases and may include intervening or adjacent land in which the United States does not own the coal. All lands in an LMU are under the control of one operator or lessee, can be developed as a single operation and are contiguous. Formations of LMUs was authorized by the Federal Coal Leasing Amendments Act of 1976, which amended the Mining Leasing Act (30 U.S.C. 181 et seq.).