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reason why the flows in the fifth entry dried when the fault was tapped in the fourth <br />entry. This would not have occurred if the source of the water was a relatively large <br />permeable unit (e.g., the Rollins Sandstone), as it would have taken much more time <br />for the entire unit to dewater to the elevation of the floor of the fourth entry. The <br />recommendation is to tap the fault in the most down-dip entry (the first entry) to <br />potentially depressurize the system in an area that can be better controlled and is out <br />of the way of mining. <br />The appazent high concentrations of dissolved carbon dioxide and the higher <br />temperatures indicate that the water is groundwater, not surface water. Compazison <br />of chemical analyses from samples of this water and other local water samples is <br />recommended to aid in verifying the source. <br />It is very possible that the actual source of the water will never be found. The origin i; <br />likely a combination of sources. the recommendation is to prepaze the mine and water <br />systems to handle the water while continuing to gather data (the best source being <br />from mining itself). <br />As you know from our visit during your inspection a few weeks ago, MCC has completed a large <br />sump area 1 t. j$jee~s <br />irtg~owwtebe~ MCC has also been authorized by the Colorado <br />Department of Public Health and the Environment to bypass the sediment ponds (IvIB-I and MB- <br />2R), as long as the water meets the dischazge parameters of the ponds. The only difference is that <br />Daphnia magna can be used for the biomonitoring tests, rather than Ceriodaphnia. <br />MCC is developing the zero entry today through the fault area. No water has yet been produced <br />from a series of small fractures in the initial fault area. Mining is being conducted with short cut <br />and bolting cycles. MCC will continue to gather data and will keep the Division informed if <br />another large inflow occurs. <br />Please contact me should you have questions. <br />Sincerely, ~,/ <br />Kathleen G. Welt, <br />Environmental Supervisor <br />cc: Henry Bazbe <br />Christine Johnston <br />Alex Papp <br />Phil Schmidt <br />Gary Witt, WWE <br />