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reclamation operations. <br />The Caldirola No. 2 mine is located immediately southeast of the planned <br />mining area of the Twin Pines No. 2 Mine. Originally, a well owned by the <br />City of Coal Creek was established in a ventilation shaft that penetrated the <br />Caldirola No. 2 underground workings. Following a collapse within the shaft <br />that destroyed the pump, a new hole was drilled nearby that connected with <br />the workings and re-established the well. This well is currently owned by the <br />City of Coal Creek and permitted for emergency use and fire suppression <br />purposes only. <br />The Caldirola No. 2 workings lie hydrologically updip from the Twin Pines <br />No. 2 workings. Mining in the Twin Pines could potentially cause <br />dewatering that could affect the water level in the Caldirola well. Since the <br />well is updip, mining in the Twin Pines No. 2 Mine would not be expected to <br />cause water quality changes in the Caldirola No. 2 well. <br />The Caldirola No. 2 well was included as an approved Twin Pines No. 2 <br />water monitoring location over the reclamation liability period until permit <br />revocation/bond forfeiture in 1996. Monitoring data shown below documents <br />no significant changes in the water level or the general quality regarding <br />dissolved solids (conductivity) or pH over the period of monitoring. <br />Caldirola No. 2 Well <br />Date Water level (feet) Cond. (umhos/cm) pH <br />May 1985 83 570 7.2 <br />i <br />July 1990 90 640 8.5 <br />June 1993 90 740 7.5 <br />Regional ground water levels were elevated in the mid-1980's due to <br />excessive winter precipitation and increased infiltration to the ground water <br />system. This would result in increases in the elevation of the groundwater <br />table as well as a slight dilution of the dissolved solids in the ground water <br />system. As the data indicates, water levels in the well declined slightly as the <br />regional climate returned to conditions closer to the average in the early <br />1990's, based on historical climate data. Given the small rate of mine water <br />inflow to the workings (approx. 38 gpm), the limited pumping of mine water <br />from the Twin Pines No. 2 Mine, and the data collected and reported for the <br />Caldirola No. 2 well, no impact to this permitted water supply is apparent. <br />Furthermore, based on evidence presented in the approved permit, the <br />Caldirola No. 2 well was completed in an isolated pool of water trapped by a <br />14