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DRMS CEMEX M1977-208 Quarterly Report <br />January 14, 2009 <br />Page 2 <br />at CEM-005 on a semi-annual basis, and in the event the well shows signs of increased water <br />volume sufficient to sample, an attempt will be made to obtain a sample. <br />Although conclusive evidence as to the source of inflow into C-Pit has not been established, The <br />Northern Colorado Water Conservancy District completed lining a portion of the Boulder Feeder <br />Canal to the southwest of the C-Pit area, in case this is a contributing source. There has been no <br />in flow of water through the west high wall in C-Pit in this quarter. Observations continue, and <br />if other significant sources of inflow can be identified, corrective actions will be evaluated. <br />To reduce water levels in C-Pit, CEMEX maintains a pump and motor sufficient to pump water <br />into the spray tower for use as cooling water. This is a consumptive use consistent with all <br />applicable permit (DRMS and CDPHE) conditions. The pump that was installed and that began <br />operation in the second quarter of 2008 has been effective in lowering the water level <br />considerably at this location. CEMEX pumped approximately 21 million gallons of water into <br />the cooling tower of the manufacturing process. CEMEX pumped C-Pit water until October 24, <br />and then winterized the pump and equipment. Water levels will be reevaluated in the second <br />quarter of 2009. CEMEX has reduced the surface area remaining in C-Pit down to approximately <br />a quarter acre of water surface area. <br />No seeps or springs down gradient of C-Pit have been observed. As agreed upon in TR-9, we <br />will continue to monitor for the presence of seeps or springs. <br />Wildlife Monitoring <br />Consistent with the mining permit and subsequent Technical Revisions, CEMEX has monitored <br />the C-Pit area daily for signs of wildlife, including the presence of tracks and wildlife itself. <br />Ducks have been seen near but not in the main pond. Pigeons, rabbits, and coyote were observed <br />in the vicinity of C-Pit. In over three years of daily monitoring, very limited wildlife has been <br />observed. CEMEX has requested permission to remove this condition of wildlife monitoring and <br />netting from the technical revision in TR-10 submitted September 24, 2008, which was approved <br />by DRMS. Future quarterly reports will continue to summarize any significant wildlife <br />observations, but daily inspections and records will no longer be required and reported on. <br />Discussion of results <br />C-Pit was originally a limestone mining pit of the Lyons Quarry; at the cessation of extraction of <br />limestone from the pit, it was converted to a cement kiln dust (CKD) disposal area associated <br />with the Lyons cement plant. The monitoring of C-Pit began based on observations of increasing <br />water in the pit, and subsequent elevated pH levels in the water. Under TR-04, a well was drilled <br />close to the CPit (CEM-001) to monitor for the potential movement of groundwater. At that <br />time, specific limits and standards were not established, because the presumptive use of the water <br />was agricultural, and a reference background source had not been established. A-Pit was <br />considered, but never finalized. The limits and parameters presented here assume agricultural <br />groundwater, which is the more conservative standard in reference to selenium. No reference to a