2012-10-01_REVISION - M1977306 (22)

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13.2 Wind Speed Wind speed data was not available at the Uravan meteorological station. Longer term wind speed records are available from the BLM and the Boise Interagency Fire Center Remote Automatic Weather Station (RAWS) in Nucla, Colorado (NUCC2), elevation 5860 ft. Based on the available data from the Nucla station from 2002 through 2012, the average annual wind speed is 5.0 mph. Winds are primarily westerly winds. As indicated in the climate data, precipitation for the Uravan site is 12.57 inches per year, whereas the evaporation is approximately 47 inches per year. The evapotranspiration rates (evaporation plus transpiration rates from area vegetation) in this semi -arid location would be higher than simple pan evaporation rates. Therefore, all rain and snow melt will infiltrate the porous dump material with very little percolating completely through the pile, the rest being returned to the atmosphere via evaporation or transpiration, or being absorbed by the dry but porous rock, leaving very little water for recharge. (14) Geochemical Data and Analysis This section discusses the results of the SPLP tests to measure the concentration of uranium related constituents leaching from waste rock and ore stockpiles. Besides uranium and vanadium, there are several constituents that are commonly associated with these types of mineral deposits. These constituents include arsenic, molybdenum, selenium, and at some sites radium. While most of these constituents occur naturally in the environment, their association with mining operations and potential for migration in the environment are examined. Analytical results from the SPLP tests are compared with the appropriate federal and state water quality regulations and guidelines. These regulations include the Safe Drinking Water Act, National Secondary Drinking Water Standards (not federally enforceable), State of Colorado Basic Standards for Groundwater (5 CCR 1002 -41), and Colorado Agricultural Standards. 14.1 Results of SPLP Tests Laboratory SPLP results for chemical constituents of interest are presented in Table 5 along with applicable water quality standards and guidelines. Both the ore and waste rock samples contain constituents above Federal or State standards or guidelines. Since the ore will be placed on a clay liner and only temporarily stored onsite and removed on a first -in first -out basis, only constituents associated with waste rock pile that will permanently remain on site will be discussed. Aluminum, arsenic, uranium and vanadium exist in concentrations that exceed Federal and State standards or guidelines. The main environmental issue concerning aluminum is potential toxicity to aquatic organisms. The EPA guidelines are for the pH range of 6.5 to 9.0 while the EPP sample at JD -9 has a pH of 9.5. In general, the more sensitive an organism is to a low pH, the stronger the toxic response to Al concentrations to falling pH levels (Baker and Schofield, 1982). Based on the site distance to the nearest water body, it is highly unlikely, even under the most extreme conditions, that aluminum could be transported such a large O'Connor Design Group Inc. U - 23