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INTRODUCTION <br />Contour Consulting Engineering, LLC, (Contour) collected groundwater samples at the <br />GCC Rio Grande, Pueblo Cement Plant, on October 13, 2011. The samples were collected <br />to satisfy monitoring permit requirements, as stipulated by the Colorado Division of Mining <br />Reclamation and Safety (DRMS). Quarterly sampling was initiated in 2008. Beginning in <br />2009, sampling was set at a semi -annual monitoring frequency. The October 2011 <br />sampling event marks the sixth semi - annual event, and the second -half semi - annual event <br />for 2011. <br />Based on communications between GCC and Behran Keffelew of the DRMS, it was <br />determined that the suite of analytes that had been required in previous sampling events <br />could be significantly reduced. The reduced compliance suite for the St Charles River <br />monitoring wells now includes sulfate, total dissolved solids (TDS), radium 226, and <br />radium 228. Previous sampling included a comprehensive list of dissolved metals, anions, <br />cations, and additional radiochemistry parameters. As part of recent semi - annual <br />monitoring reports submitted to the Division, GCC has recommended that a reduced <br />sampling suite would be appropriate for the site. This recommendation was based on <br />comprehensive analysis of the results from the larger sampling suite over the sampling <br />history for the project. Unless conditions at the site change, the new suite of monitoring <br />parameters will be used in all future monitoring events. <br />WORK PERFORMED <br />Contour collected groundwater samples from three shallow alluvial monitoring wells <br />(MW002, MW003, and MW004) in the vicinity of the St. Charles River. The alluvial wells <br />represent downgradient conditions with respect to the Cement Plant operations. Deep well <br />MWOO1A is completed in the Codell Sandstone west of the plant. This well was <br />determined to be dry during the first quarter 2008. Approximately 4 feet of water was <br />measured in this well during the second quarter 2008. One full bailer of very clear water <br />was removed from the well, and then the well went dry. Similar conditions have been <br />encountered in well MWOO1A in subsequent sampling events. During the April and <br />October 2011 events, 1.5 feet of water was measured in the well, which is essentially water <br />filling the silt cap at the bottom of the well. It has been determined that water in this well is <br />sourced by formation condensation. The well is 100 feet deep. Samples were not collected <br />from well MWOO1A. <br />During the second quarter 2008, GCC installed an additional shallow groundwater <br />monitoring well (MW005) at a location between the mine plant operations and the St. <br />Charles River (shown in Figure 1). The new well location was selected with input from the <br />DRMS. Groundwater was not encountered in the shallow aquifer at the time the well was <br />installed, and no sample was collected. The well was sounded during the second half 2008 <br />monitoring event, and was found to be dry, and no sample was collected. The well has <br />been sounded during the 2009, 2010, and 2011 semi - annual sampling events, with similar <br />results. During the October 2011 sampling, this well was determined to be bone dry. No <br />sample was collected at MW005. <br />2 <br />