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Introduction <br />The purpose of this white paper is to determine the possible impacts of applying high salinity <br />mine pit waterto soil stockpilesfor dust control purposesduring soil placement on the stockpiles <br />at the New Horizon Minein Nucla, Colorado, operated by Western Fuels-Colorado.Recently, <br />opponents of the Mine’s permit renewal application have expressed concerns that the application <br />of high salinity mine pit water to soil stockpiles for dust control could negatively impact the soil <br />resource for use in reclamation. <br />Soil sampling and analysis indicates that the electrical conductivity (EC) in soil stockpiles at the <br />New Horizon Mine is greater than the native soil EC. It has been opined that the application of <br />mine pit water to the soil stockpiles for dust control is responsible for the higher level of EC in <br />soil stockpiles. At times, the mine pit water exhibits an (EC) as great as 5,000 micromhos per <br />centimeter (umhos/cm). The goal of this white paper is to answer the following questions: <br />1)Is the use of the mine pit waterfor dust control responsible for the increase in soil <br />salinity? <br />2)If the mine pit water is not the source of the increase in soil salinity what other <br />factors may be responsible for this apparent increase? <br />3)Would the stockpile soil salinity be lower if soilhandling practices had been <br />different? <br />4)Are t proven scientific methods available to remove the salinity from the <br />stockpiled soils and return them back to native conditions, and are such methods <br />included in Western-Fuels-Colorado’s reclamation plans? <br />Conclusions <br />1)Mass balance calculations performedusing mine process water with an EC of 5,000 <br />indicate that to increase the soil stockpile salinity to their current levels at least 1.4, 2.7 <br />and 1.3-9,000 gallon water trucks per day for 365 days would have had been. In addition, <br />due to the high level of soil electrical conductivity (Ece)uniformity within the soil <br />stockpiles it is believed that the water trucks could not have physically spread the water <br />in a manner to see this type of uniform increase in soil salinity. Based on my experience <br />this type of water uniformity could only be completed with a very well-engineered <br />sprinkler irrigation system or natural precipitation;therefore there is no scientific <br />evidence that indicates the soil salinity increases in the soil stockpiles could be a result of <br />mine pit water application by a large water trucks. It is more likely that the increase in <br />soil salinity is due to natural processes. <br />2)The likely source of the soil salinity increase in the soil stockpiles is natural physical and <br />chemical weathering and dissolution reactions. The increase in soil salinity is expected <br />during mining operations whensoil material is placed into stockpiles. The high <br />uniformity of the ECe concentrations in the samples is expected due to thesoil handling <br />2 <br />{00136879.1 } <br />