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INTRODUCTION <br />Contour Consulting Engineering, LLC, (Contour) collected groundwater samples at the <br />GCC Rio Grande Limestone Mine on November 6, 2008. The samples were collected to <br />satisfy quarterly monitoring permit requirements, as stipulated by the Colorado Division <br />of Mining Reclamation and Safety (DRMS). <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 <br />wells represent downgradient conditions with respect to the Cement Plant operations. <br />Newly installed well MWOOIA is completed in the Codell Sandstone. 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. One full bailer of very clear water was <br />removed from the well, and then the well went dry. Similar conditions were encounter <br />during the Second Half, 2008 sampling. It is likely that the water produced in this well <br />was a result of formation condensation. Samples were not collected from MWOO IA. <br />The locations of all wells are provided in Figure 1. <br />' Depth-to-groundwater measurements were performed at each alluvial well prior to <br />sampling. Wells were also sounded to determine total depth. The volume of standing <br />water in each well was determined. Each of the alluvial wells were purged using a new <br />' disposable poly bailer. A minimum of three casing volumes was purged from each well <br />prior to sampling. Field parameters pH, conductivity, and temperature were recorded as <br />each well volume was removed. Groundwater was purged until these parameters were <br />stabilized and reproducible (typically after three or four measurement sets). <br />All groundwater samples were submitted to Evergreen Analytical Laboratory, located in <br />' Wheat Ridge Colorado, for analysis. Evergreen subcontracted analyses for radiochemical <br />parameters to Hazen Research, located in Golden, Colorado. <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 <br />the DRMS. Groundwater was not encountered in the shallow aquifer at the time the well <br />was installed, and no sample was collected. The well was sounded during the Second <br />' Half, 2008 monitoring event, and was found to be dry, and no sample was collected.