2002-07-08_GENERAL DOCUMENTS - M2002004 ‎(2)‎

• Permit No: M2002004
• IBM Index Class Name: GENERAL DOCUMENTS
• Doc Date: 7/8/2002
• Doc Name: ATTACHMENT, PART 1
• From: HABITAT MGMT
• To: DRMS
• Media Type: D
• Archive: No

•
III. Two Approaches to Topsoil Reduction
RH /JS/5 -88
JM/7 -91
Update /8 -95
A. Reduction to 18 inches
as overburden material and handled in accordance with the
requirements of this section.
Requests from mining companies have been made to reduce soil salvage and
replacement to a specific depth (generally 12 inches). Studies conducted • in
Wyoming have shown that approximately 18 inches of soil are required to
optimize vegetative production on reclaimed land (Barth and Martin, 1984 and
Pinchak et al., 1985). Without further studies or adequate demonstration, 18
inches will be used as the minimum level for mines with an excess of topsoil.
Mines with less than 18 inches of available soil will not be eligible for soil
reductions of this type. Information and additional monitoring required to justify
a reduction to 18 inches is listed below.
1. Comparisons of spoil and subsoil horizon chemical quality using the
following parameters: organic matter, NO3 -N, NH4 -N, and P. The
purpose is to determine if regraded spoil is as productive as C and lower
B horizon material, thus making salvage of these horizons nonessential to
reclamation.
2. Comparisons of A and subsoil horizon organic matter contents to show
that dilution of topsoil with material from particular subsoil horizons will
significantly reduce topsoil quality. A 0.5 % organic matter content is
needed in soils to ensure establishment of nutrient cycling (Schuman,
personal communication). Thus, if dilution reduces organic matter
contents below this level, topsoil quality is diminished.
3. Upgrade regraded spoil monitoring program. With reduced topsoil
replacement depth, spoil quality becomes a greater concern because it will
make up a larger proportion of the root zone.
a. increase sampling intensity to 250 foot centers
b. include other parameters - coarse fragments, texture
B. Reduction based on Adequate Demonstration
Adequate demonstrations will be in the form of scientifically designed field
studies or existing reclamation plots. Exiting reclamation will be from prelaw
reclaimed lands or from shallow topsoil pits at multi -pit mines The purpose of
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