APPCOR11480

• Permit No: C1980006
• IBM Index Class Name: Application Correspondence
• Doc Date: 12/23/1980
• Doc Name: KERR NORTH PERMIT APPLICATION FN 80-157 RESPONSES TO 12-05-1980 ADEQUACY REVIEW
• From: KERR COAL CO
• To: MLRD
• Media Type: D
• Archive: No

Carol Pahlke
December 23, 1980
Page 10
Pit #1 Area. Since the documented infiltration rate
for the soils within the Pit #1 Area fall within the
acceptable limits for irrigated croplands, one can
assume that they are satisfactory for the production
of native plant communities. The potential problem
of poor soil structure reducing infiltration and
permeability rates is also unfounded. As previously
discussed, these soils are normal with respect to
salinity and hence the salt levels do not have the
potential of adversely affecting soil structure. it
thus follows that the quality of both topsoil and
spoil is suitable plant growth medium with respect
to the above concerns from a chemical standpoint.
Moreover, infiltration rates and permeability are
increased through the use of chisel plowing and
mulching practices~at Pit #1 and throughout the
permit area. The proposed chisel plowing, as
detailed in the Permit Application, will relieve any
problems of soil compaction. Furthermore, because
the chisel points will go below the respread topsoil
into the spoil, the formation of an impermeable
interface between the topsoil and spoil will be
virtually eliminated. Mulching also enhances the
soil in these respects by adding organic matter and
pore spaces due to root growth. These reclamation
practices are addressed in Section 780.18 of the
Permit Application.
with respect to concerns regarding the clay content
of the spoil, Table 76, Texture Analysis of Over-
burden Raw Data, reveals texture classes of loam,
sandy clay and clay, with clay content ranging from
15 to 61 percent. From Table 42a, Soil Chemical and
Physical Properties Lab Analysis Kerr North Area, it
can be seen that topsoil clay content for the Coal-
mont (X73) soil type ranges from 50 to 73 percent,
and subsoil from 65 to 76 percent.
Application of Wyoming and Montana Guidelines to the
overburden samples from Pit #1 (from Table 73a and
Table 76) indicates that texture is the only param-
eter of concern here. Yet, from the information
above, it can be seen that the overburden actually
has lower clay content than either the topsoil or
subsoil. Average clay content of the overburden
after mixing is about 488, a content significantly
lower than the B horizon of the soil. These facts
make clear that there is no advantage to a separate