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

• from lab data: pH =5.9 (moderately acid), EC =0.2 (nonsaline), SAR =O. (nonsodic),
OM =7.4 %; gradual smooth boundary.
A2 horizon — 5 to 16 inches; very dark grayish brown (10YR 3/2) sandy loam with 10%
small angular sandstone gravel -size fragments; very dark brown (10YR 2/2) moist;
moderate medium granular structure; slightly hard, very friable, slightly sticky and
slightly plastic consistence; many medium, fine, very fine, and common coarse roots;
noneffervescent; from lab data: pH =6.0 (moderately acid), EC =0.2 ( nonsaline),
SAR =0.2 (nonsodic), OM =7.2 %; gradual wavy boundary.
A3 horizon — 16 to 24 inches; dark grayish brown (10YR 4/2) sandy loam with 15%
small angular sandstone gravel -size fragments, very dark grayish brown (10YR 3/2)
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 =6.4 (slightly acid), EC =0.2 (nonsaline),
SAR =0.2 (nonsodic), OM =6.9 %; gradual wavy boundary.
C horizon — 24 to 35 inches; pale brown (10YR 6/3) sandy loam with 15% small angular
sandstone gravel -size fragments, brown(10YR 5/3) moist; massive structure; slightly
hard, friable, slightly sticky and slightly plastic consistence; few coarse, medium, fine,
and very fine roots; noneffervescent; from lab data: pH =6.8 (neutral), EC =0.2
(nonsaline), SAR =0.2 (nonsodic), OM =1.0 %; gradual wavy boundary.
• 3.3.5 Map Unit 66C: Skylick loam, 5 to 10% slopes
Skylick was previously re- correlated to the Foidel soil series but the Skylick name is
retained for potential surface- affected areas within the Sage Creek Mine project because it
is part of both the Seneca II Mine and Foidel Creek Mine soil legends. The Foidel name is
used for non - affected areas. Skylick is an established soil series of moderate extent
mapped in the mountainous areas of north - central Colorado, and is classified as a "Fine -
loamy, mixed, superactive Pachic Palecryoll ". Diagnostic features for the typical pedon
include a mollic epipedon from 0 to 24 inches in depth, and the depth to the upper
boundary of the argillic "Bt" horizon ranges from 24 to 35 inches. The most recent official
NRCS soil series description for Sylick, dated February 1999, is on file.
An evaluation of soil suitability indicates the sampled Skylick pedon CC -5 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 -5 is 28 inches, slightly more than 26 inches but consistent with it.
Skylick Typical Sample "CC -5" Site and Soil Profile Description: Skylick loam in Map
Unit 66C was fully described and sampled at one representative site, CC -5, located in a
portion of the SW1 /4 of the NE1 /4 of Section 34, T.6N., R.87W. The sample site is on a
sloping ridge lower sideslope (bowl feature) within the previous potential waste rock
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