coal seam

(6) The term “coal seam” means any stratum of coal 20 inches or more in thickness, unless a stratum of less thickness is being commercially worked, or can in the judgment of the Secretary of the Interior forseeably be commercially worked and will require protection if wells are being drilled through it.

Source

42 USC § 13368(p)(6)


Scoping language

As used in this section
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