PERMFILE117745

• Permit No: C1982055
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: ADDENDUM A SUITABILITY EVALAUATION OF THE RATON CREEK MINE REFUSE COVER MATERIALS
• Media Type: D
• Archive: No

• III, pits 5 and 6, and Soil Test Area V, pits Al-A4, (depicted on Permit Map
No. 1) correspond directly to the area sampled in the present evaluation.
Soil pits 5 and 6 appear to correspond to soils derived from colluvial
materials while pits Al-A4 are derived from soils formed from shales.
Evaluation of the soil textures and rock content readily allow for a
separation of colluvial and shale derived soils on this site. Unfortunately,
none of these soils pits appear to have been made on sandstone derived soils.
Soil texture was determined on 12 horizons from these 6 holes. Clay textures
were associated with 58.3 percent of the horizons, clay loams with 33.3
percent and loam textures were associated with the remaining 8.4 percent of
the samples. Upon applying the Wyoming DEQ topsoil substitute suitability
criteria, 58.3 percent of these soils rank as being of "marginal" suitability
with respect to clay content. The clay loam textures would be enriched with
clay during removal and would be considered as being of "marginal"
suitability with respect to clay content.
Therefore, half of the existing colluvial materials would presently be
ranked "marginal" and considering the mixing which will occur, all of the
colluvial materials and most of the shale derived overburden materials would
ultimately be classified as being of "marginal" suitability as topsoil
substitute materials. In total, 51.12 percent of the overburden samples and
91.6 percent of the topsoil samples collected from this area appear to be of
limited suitability as potential topsoil substitute materials due to their
heavy texture. Given these results, the proposed cover material, although
not "suitable" according to the Guidelines, is of higher quality than the
• topsoil material approved for redistribution over the refuse area and thus
should pose no problems with respect to reclamation success.
Sodium Adsorption Ratio (SAR). The Wyoming Guidelines rank topsoil
substitute materials as being of "suitable" quality with respect to SAR when
the values are less than 10. Examination of the Raton Creek Mine overburden
and bench materials reveals that the SAR values range between 0.3 and 9.0
with a weighted mean value of 1.15, meaning that all of the materials possess
a "suitable" quality as topsoil substitute materials. These data therefore
suggest, that all of the Raton Creek Mine overburden and bench materials
possess a "suitable" quality with respect to sodicity.
Selenium (Se). The Wyoming Guidelines rank topsoil substitute materials as
being of "suitable" quality when the water soluble Se values are less than
0.1 ppm. The Raton Creek Mine overburden and bench materials were found to
range from a low of < 0.01 to a maximum of 0.06 with a weighted mean value
of 0.009 mg/kg, suggesting that all of these materials possess a 'suitable"
quality as overburden materials. Given the relatively low Se values
associated with these materials, no problems appear to be associated with the
overburden and bench materials with respect to Se toxicities.
Boron (B). The Wyoming Guidelines rank topsoil substitute materials as being
of "suitable" quality when the hot water soluble B values are less than or
equal to 5 ppm. The B values for the Raton Creek Mine overburden and bench
materials were found to range between < 0.1 and 0.2 with a weighted mean of
0.114 mg/kg, suggesting that all of these materials possess a "suitable"
• quality as overburden materials. Given the relatively low values associated
with B, there appears to be no potential adversity related to the B content
of these materials.