2009-12-29_REVISION - C1981019

• Permit No: C1981019
• IBM Index Class Name: REVISION
• Doc Date: 12/29/2009
• Doc Name: Colowyo TR84 Initial Submittal with Text Changes
• From: Colowyo Coal Company
• To: DRMS
• Type & Sequence: TR84
• Email Name: JRS
• Media Type: D
• Archive: No

chemical properties. Soil pH ranges from 6.9 to 7.8, macronutrients appear to be
adequate for sustained plant growth, organic matter contents are relatively high (3.7% to
6.3%), salt levels are low (EC ranges from 0.6 to 1.6 mmhos/cm and SAR ranges from
0.3 to 1.8), cation exchange capacity (CEC) is in a normal range, and textures are clay
loam and sandy clay loam. Overall, topsoil and spoil at all mine sites have favorable
characteristics and provide a suitable plant growth medium.
At Colowyo, soil pH ranges from 7.5 to 7.8, macronutrients appear to be adequate for
sustained plant growth, organic matter contents are relatively high (3.7% to 4.8%), salt
levels are low (EC ranges from 0.6 to 1.2 mmhos/cm and SAR ranges from 0.3 to 1.6),
cation exchange capacity (CEC) is in a normal range, and textures are clay loam and
sandy clay loam. The detailed soil and overburden analysis for the Colowyo Mine is
provided below.
Plot la Plot 2b Plot 3e Plot 4d Plot 5e
Parameter
pH 7.5 7.5 7.5 7.7 7.8
% OM 4.1 4 4.8 4.1 3.7
NHa-N mg/kg
4.9 4.6
6
6.1
8.7
N03-N mg/kg 24.1 19.1 22.3 13.7 18.1
P mg/kg 15 9.6 12 7.8 29
K mg/kg 191 210 201 95.1 105
Ca meq/L 4.9 4.1 4.4 3.5 5.5
Mg meq/L 2.6 1.6 2 2.4 4.1
Na meq/L 0.8 0.6 1.3 1.9 3.5
K meq/L 0.2 0.5 0.4 0.2 0.2
EC mmhos/cm 0.7 0.6 0.7 0.7 1.2
SAR 0.4 0.3 0.8 1.1 1.6
CEC meq/100g 26.8 22.1 22.9 27 23.3
% Sand 41 51 48 39 41
% Silt 23 23 23 23 25
% Clay 36 26 29 35 35
Texture clay loam sandy clay loam sandy clay loam clay loam clay loam
aplot 1 = 18 inches of topsoil, strip seeding i n alternate rows.
bplot 2 = 6 inches of topsoil and surface manipulation, seeded with native shrubs and
low competitive forbs.
Plot 3 = 6 inches of topsoil, strip seeding in alternate rows.
dPlot 4 = Non-topsoiled spoil, strip seeding in alternate rows.
ePlot 5 = Non-topsoiled spoil, seeded with unpalatable native shrubs and low
competitive forbs and grasses.
To evaluate the impact from wildlife browsing, elk proof fencing was construc ted on one-
half of each treatment.
4.15-7 Revision Date: 12/22/09
Revision No.: TR-84