2011-06-20_PERMIT FILE - C1982056A ‎(5)‎

• Permit No: C1982056A
• IBM Index Class Name: Permit File
• Doc Date: 6/20/2011
• Section_Exhibit Name: 2.04 Environmental Resources
• Media Type: D
• Archive: Yes

Interpretation of Overburden Geochemical Data
• All parameters required for analysis by the CMLRD and contained herein were compared with the overburden
suitability ratings developed by the Wyoming Department of Environmental Quality and the Montana Department
of State Lands to determine what potential limitations might exist relative to revegetation and hydrologic
considerations. Each parameter is discussed below:
PH - The average pH value was found to be 7.8 with a range from 6.2 to 8.9. According to the Wyoming DEQ
Guideline No. 1, the reclamation suitability of these roof and floor materials would be rated good, as shown on Tables
20B and 20C. According to the criteria published by the Montana Department of State Lands, only one of these pH
values exceeds the suspect level of 8.8. Based on the results from a total of 20 samples, TCC believes that the pH of
the roof and floor materials presents no problem for revegetation or waterquality.
Electrical Conductivity - The average electrical conductivity of these roof and floor samples was 2.1 mmhos /cm with
a range of 0.6 to 3.9 mmhos /cm. The electrical conductivity values represented by these data fall within the range of
normal soils and do not present potential reclamation problems.
Boron - The average boron concentration was found to be 0.6 ppm with a range of 0.2 to 1.2 ppm. According to the
guidelines used by the Montana Department of State Lands, the suspect level of this paemeter is 8ppm. Since all
boron values are well below this value, no potential problem of boron appears likely.
Nitrate Nitrogen - The range of nitrate nitrogen content of these samples was found to be less than 0.02 up to 6.35
ppm. According to the guidelines of the Montana Department of State Lands, the suspect level for nitrate nitrogen is a
value greater than 20 ppm. None of our values reached this level.
• Nitrite Nitrogen -Only two of the twenty samples collected were above the laboratory detectim limit of 0.1. Due to
the presence of such low nitrite nitrogen values no reclamation problems seem probable regarding this parameter.
Selenium - Only nine of the twenty samples analyzed were above the laboratory detection limit of 0.01 ppm, with the
highest concentration being only 0.2 ppm. Due to the presence of such low selenium values, it is unlikely that
reclamation problems exist relative to this parameter.
Tables 20B and 20C. According to the criteria published by the Montana Department of State Lands, only one of
these pH values exceeds the suspect level of 8.8. Based on the results from a total of 20 samples, TCC believes that
the pH of the roof and floor materials presents no problem for revegetation or water quality.
Textural Analysis - The average particle size of all nine samples analyzed was 57 percent sand, 32 percent silt and 11
percent clay, which yielded an average texture of sandy loam. this texture, according to the Wyoming DEQ, has a
suitability ranking of fair. This is little ikelihood that any adverse impacts on revegetation success or water quality
can be expected due to texture.
Total Combustible Solids - The average total combustible solids of all twenty samples was 6.8 percent. The range of
the twenty samples is from 2.7 to 10.3 percent. The potential of these strata presenting a fire hazard remains remote.
Saturation Percentage - The average saturation percentage of all nine samples was 31 percent with a range of 26 to
40 percent. According to the Wyoming Guidelines, overburden with saturation percentages of 25 to 80 are considered
to have a good to fair reclamation suitability.
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APPROVED ,l!! l 2 3 iu 0
PR -05 2.04 -17 5/26/00