THICK OVERBURDEN:

1. A. The provisions of 19.8.20.2058 NMAC apply only where the overburden thickness times the swell factor exceeds the combined thickness of the overburden and coal bed prior to removing the coal and only when surface mining activities cannot be carried out to comply with 19.8.20.2054 NMAC to achieve the approximate original contour.

2. B. In surface mining activities where the volume of spoil over the permit area is demonstrated to be more than sufficient to achieve the approximate original contour, surface mining activities shall be conducted to meet, at a minimum, the following standards:

   (1) haul or convey, backfill, and grade all spoil and wastes, not required to achieve the approximate original contour of the permit area, to the lowest practicable grade, to achieve a static factor of safety of 1.3 and cover all acid-forming and other toxic- forming materials;

   (2) haul or convey, backfill, and grade excess spoil and wastes only within the permit area and dispose of such materials in accordance with 19.8.20.2034 through 2037 NMAC;

   (3) haul or convey, backfill, and grade excess spoil and wastes to maintain the hydrologic balance, in accordance with 19.8.20.2009 through 2025 NMAC and to provide long-term stability by preventing slides, erosion and water pollution;

   (4) haul or convey, backfill, grade and revegetate wastes and excess spoil to achieve an ecologically sound land use approved by the director as compatible with the prevailing land uses in unmined areas surrounding the permit area;

   (5) except as provided for in Paragraph (2) of Subsection A of 19.8.20.2055 NMAC and Paragraph (1) of Subsection B of 19.8.20.2053 NMAC, eliminate all highwalls and depressions by backfilling with spoil and suitable waste materials; and

   (6) meet the revegetation requirements of 19.8.20.2060 through 2066 NMAC for all disturbed areas.

   [11-29-97; Rn, 19.8.20.2058 NMAC - 19 NMAC 8.2.20.2058, 9-29-2000; A, 1-15-2002]