2010-05-07_PERMIT FILE - C2009087 ‎(14)‎

• Permit No: C2009087
• IBM Index Class Name: Permit File
• Doc Date: 5/7/2010
• Doc Name: Soils Information
• Section_Exhibit Name: Exhibit 2.04.9-E1 Soils Information
• Media Type: D
• Archive: No

• stockpile site outside of but adjacent to the current Seneca II Mine permit area. Sample
site CC -5 has 6% slope; NNE aspect; mixed grasses with some scattered big
sagebrush vegetation; slopewash alluvium over residuum at depth; stable surface with
none to slight erosion in the vicinity of the sample site location.
Al horizon — 0 to 5 inches; brown (10YR 5/3) loam, dark brown (10YR 4/3) moist;
moderate medium granular structure; soft, friable, slightly sticky and slightly plastic
consistence; common medium, fine, and very fine, and few coarse roots; noneffervescent;
from lab data: pH =6.1 (slightly acid), EC =0.3 (nonsaline), SAR =0.3 (nonsodic), OM =5.7 %;
gradual smooth boundary.
A2 horizon — 5 to 16 inches; brown (10YR 5/3) loam, dark brown (10YR 4/3) moist;
moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and
slightly plastic consistence; common medium, fine, very fine, and few coarse roots;
noneffervescent; from lab data: pH =6.1 (slightly acid), EC =0.2 (nonsaline), SAR =0.4
(nonsodic), OM =3.8 %; gradual wavy boundary.
Bt1 horizon — 16 to 28 inches; dark brown (10YR 4/3) clay (43% clay), dark yellowish
brown (10YR 4/4 moist); moderate medium subangular blocky structure; hard, firm, sticky
and plastic consistence; few medium, coarse, fine, and very fine roots; noneffervescent;
from lab data: pH =6.4 (slightly acid), EC =0.2 (nonsaline), SAR =0.4 (nonsodic), OM =1.6 %;
gradual wavy boundary.
• Bt2 horizon — 28 to 40 inches; yellowish brown (10YR 5/4) to light olive brown (2.5Y 5/4)
clay (47% clay), dark yellowish brown (10YR 4/4) to olive brown (2.5Y 4/4) moist; massive
structure parting to moderate medium subangular blocky structure grading to massive
structure; very hard, very firm, sticky and plastic consistence; noneffervescent; from lab
data: pH =7.2 (neutral), EC =0.3 (nonsaline), SAR =0.6 (nonsodic), OM =0.8 %; gradual wavy
boundary.
C horizon — 40 to 64 inches; light olive brown (2.5Y 5/4) clay (43% clay), olive brown (2.5Y
4/4) moist; massive structure; very hard, very firm, sticky and plastic consistence;
noneffervescent with slightly effervescent spots; from lab data: pH =7.6 (slightly alkaline),
EC =0.3 (nonsaline), SAR =0.7 (nonsodic), OM =0.3 %; gradual wavy boundary; did not hit
shale bedrock.
3.3.6 Map Unit 66D: Skylick loam, 10 to 20% slopes
Skylick loam (Map Unit 66D) is the same soil as in Map Unit 66C except the slope class is
10 to 20 percent rather than 5 to 10 percent slopes. An evaluation of soil suitability
indicates the sampled Skylick pedon CC -2 is consistent with the previous Seneca II Mine
recommended topsoil salvage depth of 26 inches for Map Unit 66C. The thickness of the
mollic epipedon plus the upper subsoil horizon for sample site CC -2 is 27 inches, slightly
more than 26 inches but consistent with it.
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