PERMFILE70564

• Permit No: C1981019
• IBM Index Class Name: Permit File
• Doc Date: 5/4/2007
• Doc Name: Soil Inventory Danforth Hills Project Report Dated 12/17/1984
• Section_Exhibit Name: Exhibit 09 Item 7 -ST
• Media Type: D
• Archive: No

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shale, which is characteristic of soils nigh in selenium. Results of .
selenium tests are also in appendix B.
The K factors (erodibility) were calculated by the lab for each
sample based on the percent silt, very fine sand, clay and organic
matter. Wischmeier's formula (1978) fob the first approximation of K
was used. It is lUUK = 2.1M (1.14)(10 )(1'L-a) where M = (% si + %
VFS) (lUU-% clay) and a = organic matter content. Where "a" was
greater Than 12, a zero K factor was reported. The erodibility
factors reported are generally lower than those reported for the
series by the SCS. For soils with erodibility factors reported as
zero, a K-factor of U.U1 should be used in erosion calculations.
Based on the laboratory data and the physical properties observed
in the typical pedons, each horizon of each typical pedon was rated
for its suitability for use in reclamation. The laboratory data were
used to evaluate each six inch interval from the composite samples.
The ratings were based on criteria established by the coal industry as
shown on table 3.1-1. Each horizon was rated suitable (good, fair, or
marginal) or unsuitable. All of the pedons are rated suitable from the
surface to bedrock or 6U inches except the Thornburgh, Waybe', and the
Torriorthents.
Many of the soils of the site have thick dark surface horizons
1 (mollic epipedons). These horizons are distinctly better for •
reclamation than the subsoils, even though both are rated suitable.
To maximize reclaimed topsoil quality, the mollic epipedons were
indicated as lift 1 material even though they may not be handled
separately. The subsoils are indicated as lift 2 materials. The
average thickhess of lift 1 (mollic epipedon) for each series was
calculated from the sorted series list. The average thickness of the
second lift for each series was calculated by subtracting the average
thickness of the first lift from the depth to bedrock or inhibiting
horizon in the typical pedon.
Weighted salvage thickness by map unit was calculated based on
the salvage thicknesses of the soil series that comprise the map unit.
The percentages of the map unit occupied by the component soils were
multiplied by the thickness of the lift, the weighted thickness
summed, and the result divided by 100. For example map unit XY is 6U%
X and 4U% Y; in soil X lift 1 is suitable to 3U inches and in soil Y
it is suitable to 20 inches. The weighted salvage thickness of lift 1
for map unit XY is:
6U% x 3U in.) + (4UX x ZU in.) = 26 in.
lUU
This figure will give the most realistic maximum value for soil
volume available for reclamation when multiplied by an acreage of
l affected area for the particular map unit. This figure is an average
J stripping depth for the map unit. Table 3.2-1 provides the components.
of the individual wieyhted salvage thickness calculations for the
mapping units within the study area.
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