Current through Register Vol. 35, No. 18, September 24, 2024
To prevent topsoil from being contaminated by spoil or waste
materials, the permittee shall remove the topsoil as a separate operation from
areas to be disturbed. Topsoil shall be immediately redistributed according to
the requirements of Paragraph (b) [now Subsection B of 19.8.36.27 NMAC] of this
section on areas graded to the approved postmining configuration. The topsoil
shall be segregated, stockpiled and protected from wind and water erosion and
from contaminants which lessen its capability to support vegetation if
sufficient graded areas are not immediately available for
redistribution.
A. Topsoil removal.
All topsoil to be salvaged shall be removed before any drilling for blasting,
mining or other surface disturbance.
(1) All
topsoil shall be removed unless use of alternative materials is approved by the
regulatory authority in accordance with Subparagraph (4) [now Paragraph 4 of
Subsection A of 19.8.36.27 NMAC]. Where the removal of topsoil results in
erosion that may cause air or water pollution, the regulatory authority shall
limit the size of the area from which topsoil may be removed at any one time
and specify methods of treatment to control erosion of exposed
overburden.
(2) All of the A
horizon of the topsoil as identified by soil surveys shall be removed according
to Paragraph (a) [now Subsection A of 19.8.36.27 NMAC] and then replaced on
disturbed areas as the surface soil layers. Where the A horizon is less than
six inches, a six-inch layer that includes the A horizon and the unconsolidated
material immediately below the A horizon (or all unconsolidated material if the
total available is less than six inches) shall be removed and the mixture
segregated and replaced as the surface soil layer.
(3) Where necessary to obtain soil
productivity consistent with postmining land use, the regulatory authority may
require that the B horizon or portions of the C horizon or other underlying
layers demonstrated to have comparable quality for root development be
segregated and replaced as subsoil.
(4) Slected overburden materials may be used
instead of, or as a supplement to, topsoil where the resulting soil medium is
equal to or more suitable for vegetation, and if all the following requirements
are met:
(a) The permittee demonstrates that
the selected overburden materials or an overburden-topsoil mixture is more
suitable for restoring land capability and productivity by the results of
chemical and physical analyses. These analyses shall include determinations of
pH, percent organic material, nitrogen, phosphorus, potassium, texture class
and water-holding capacity, and such other analyses as required by the
regulatory authority. The regulatory authority also may require that results of
field-site trials or greenhouse tests be used to demonstrate the feasibility of
using such overburden materials.
(b) The chemical and physical analyses and
the results of field-site trails and greenhouse tests are accompanied by a
certification from a qualified soil scientist or agronomist.
(c) The alternative material is removed,
segregated and replaced in conformance with this Section.
B. Topsoil Redistribution.
(1) Regraded land shall be scarified or
otherwise treated to eliminate slippage surfaces and to promote root
penetration.
(2) Topsoil shall be
redistributed in a manner that:
(a) achieves
an approximate uniform thickness consistent with the postmining land
uses;
(b) prevents excess
compaction of the spoil and topsoil; and
(c) protects the topsoil from wind and water
erosion before it is seeded and planted.
C. Topsoil storage. If the permit allows
storage of topsoil, the stockpiled topsoil shall be placed on a stable area
within the permit area where it will not be disturbed or be exposed to
excessive water, wind erosion or contaminants which lessen its capability to
support vegetation before it can be redistributed on terrain graded to final
contour. Stockpiles shall be selectively placed and protected from wind and
water erosion, unnecessary compaction, and contamination by undesirable
materials either by a vegetative cover as defined in Section 715.20(g) or by
other methods demonstrated to provide equal protection such as snow fences,
chemical binders and mulching. Unless approved by the regulatory authority,
stockpiled topsoil shall not be moved until required for redistribution on a
disturbed area.
D. Nutrients and
soil amendments. Nutrients and soil amendments in the amounts and analyses as
determined by soil tests shall be applied to the surface soil layer so that it
will support the postmining requirements of Section 715.13 and the revegetation
requirements of Section 715.20.
