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In accordance with the initial CKD disposal plan submitted under TR-Ol, CEMEX was required to sample the water in the C-Pit and the adjacent A-Pit for field parameters as well as for selenium and thallium. In 2004 CEMEX reported elevated pH and selenium values within the confined waters of C-Pit where CKD is disposed (350 ug/1 for selenium). A secondary sample taken by CEMEX confirmed the elevated values. The Division obtained its own samples from C-Pit which noted a pH of 12 and selenium concentration of 184 ug/L. As a result of the high pH and selenium in the C-Pit water, the Division requested CEMEX to file a ground water response plan, ground water mitigation plan and a wildlife report. CEMEX modeled the potential impact of C-Pit water on groundwater quality in the underlying Dakota sandstone aquifer using a groundwater flow and transport model. 'The results of the analysis indicate that none of the constituents will adversely impact Dakota sandstone groundwater quality. In addition, CEMEX provided a Wildlife Resource Assessment Report to determine what impacts may occur to wildlife and migratory birds as aresult of C-Pit water. The report was forwarded to the Division of Wildlife and the US Fish and Wildlife for their comments. The long term solution involves the removal of the water and prevention of further excess accumulation of water in the pit. Until the water is removed from the pit, CEMEX is required to monitor the use of the C-Pit by migratory birds including birds protected by the Endangered Species Act. CEMEX also installed an 8-foot high gate on the access road and placed and 8-foot high construction fence along the leading edge of the bank to prevent deer from entering the area. In 2005 Technical Revision 04 ("TR-04") was submitted to add detection wells in the Fort Hayes formation and revise the current monitoring plan. The monitoring plan includes quarterly sampling of C-Pit and the detection wells for dissolved selenium, dissolved thallium, pH, total dissolved solids; sulfates and chlorides. CEMEX proposed to reduce pH and selenium' levels in C-Pit by continuing to pump the water out until the pond reaches its minimum depth and steady-state size based on the limitations of the submersible pump. The pumping lowered the water level by approximately four feet until it had to be terminated in August 2005 due to continuing problems with precipitated solids clogging the system and impacting plant operation. Technical Revision 06 ("TR-06") was submitted to the Division in January of 2006 requesting that water from C-Pit be pumped continuously into the spray tower of the cement plant at a higher flow rate while lowering the pH of the water. Technical Revision 07 ("TR-07") was submitted to the Division in March of 2006 to address a conceptual design and cost estimate for a biological water treatment system to remove selenium from water that has accumulated in the C-Pit. The reclamation bond was increased in additional $735,000.00 to address treatment of the water in the C-Pit to ensure reclamation of the pit. The final reclamation plan for the C-Pit is to backfill the pit with CKD to approximately the top of the existing highwalls. Two feet of compacted clay will be placed on top of the CKD and 6- 12" oftopsoil will be placed on top of the clay barrier. The final surface of the reclaimed land will be mounded to inhibitrun-on and promote drainage off the area. While the water in the C-Pit has contained elevated levels of selenium ranging from 350 ug/L to 540 ug/L and a pH of 12 for a number of years, CEMEX has currently not violated any of the conditions of the permit, the Colorado Land Reclamation Act for the Extraction of Construction Materials ("Act") or the Construction Material Rules and Regulations.