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It's also fairly obvious that flows from the other ponds on this site, specifically <br />Ponds B, C and D could also easily flow into the FMC due to the limited capacity <br />of the DTD. It seems that the water quality of the FMC can be degraded by <br />these settling pond discharges as well as the overall capacity of the FMC could <br />be exceeded if a storm in this area is large enough to have all the ponds <br />discharging over the emergency spillways, which will definitely enter into the <br />FMC from the DTD. The FMC was originally designed for some storm inflow <br />capacity but due to the unstable nature of the soils along the whole length of the <br />canal and the fact that the mine settling ponds are not lined; additional <br />groundwater is introduced into the soils under the canal and could potentially <br />cause seepage and slumping of this area. Much of the FMC has been lined with <br />concrete and shotcrete over the years to alleviate some of these concerns, but <br />now there are several ponds located above the FMC; Pond F is very close to and <br />above the FMC, and will now re-introduce ground water into that area. Also <br />Pond F is located in a steeper section of terrain where it would be easier to <br />cause movement when additional water is introduced into the ground. The <br />downhill side of Pond F is embankment, approximately 5 to 10 feet high, that way <br />compacted but it was not known if any tests were performed to see if the <br />compactive effort met any minimum criteria. The state has requirements for <br />construction of settlement ponds at coal mines but they were not available at the <br />time of this site visit. An observation well was installed in this area at the outside <br />edge of this embankment, but it is read quarterly on a set schedule. It is <br />unknown if any readings have been taken when the pond is full or not. It is also <br />unknown if the level in the pond is noted when each well reading is taken but in <br />follow-up discussions with the state Division of Minerals and Geology personnel, <br />the level of the water in the ponds apparently are not noted during these <br />readings. There is no staff gage or other measuring device in the pond to <br />provide a reading for the pond when the well is read so any indication of how full <br />the pond is would be rather subjective. It is also unknown if readings on <br />groundwater were taken prior to construction of and use of Pond F so it's <br />unknown if the pond really does add water to the ground water in this area. This <br />information may be available with the Colorado Division of Minerals and Geology <br />(DMG) who provide oversight for this mine. <br />State of Colorado discharge permit #CO-0044776 (signed July 27, 2004, <br />effective September 1, 2004) lists the DTD as unclassified and as such no water <br />quality standards exist for this water and no assimilative capacities are <br />determined for discharges to Deer Trail Ditch. The travelers understood this to <br />mean that there are no water quality requirements beyond what is spelled out in <br />the permit noted above, which appears minimal. But we have also been <br />informed by the state Water Quality Control Division and the Division of Minerals <br />and Geology that mine operations and discharges can not cause injury, though it <br />is not fully understood what that may include. <br />5 <br />