(a) Surface coal mining and reclamation operations shall be conducted to preserve, throughout the mining and reclamation process, the essential hydrologic functions of alluvial valley floors not within an affected area. These functions shall be preserved by maintaining those geologic, hydrologic and biologic characteristics that support those functions.
(b) Surface coal mining and reclamation operations shall be conducted to reestablish, throughout the mining and reclamation process, the essential hydrologic functions of alluvial valley floors within an affected area. These functions shall be reestablished by reconstructing those geologic, hydrologic and biologic characteristics that support those functions.
(c) The characteristics that support the essential hydrologic functions of alluvial valley floors are those in §12.202(b)(3) of this title (relating to Surface Coal Mining and Reclamation Operations on Areas or Adjacent to Areas Including Alluvial Valley Floors in the Arid or Semiarid Areas West of the 100th Meridian) and those other geologic, hydrologic, or biologic characteristics identified during premining investigations, or monitoring conducted during the surface coal mining and reclamation operation.

Source Note: The provisions of this §12.610 adopted to be effective April 7, 1997, 22 TexReg 3093.