Laserfiche WebLink
2012 AHR <br />McClane & Munger Canyon Mines Page 6 <br />however, GW -10 was sealed in 2012 since a large coal mine waste pile is no <br />longer planned and therefore GW -10 is no longer required. Baseline data for <br />Table 5 from the 1981 & 1986 monitoring is also shown. Baseline data for GW -9 <br />for the period October 2007 through September 2008 is included. Results of <br />quality sampling are consistent with the results from previous years. GW -4 was <br />in close proximity to a hay field that is irrigated during dry periods and in danger <br />of being eroded with an oxbow has been replaced with GW -3. GW -3 is located <br />adjacent to the road south of GW -4 and should be outside of the influence of the <br />irrigation of the hay field. Refer to Figure 4.2 -2 of the McClane Canyon Permit. <br />The Division of Reclamation, Mining and Safety has approved this substitution. <br />Ground water wells GW -2, GW -4, GW -7, and GW -8 were sealed during 2007. <br />Pond Discharges <br />There was no discharge from the McClane or Munger sediment ponds during the <br />water year. The sediment fences at McClane, Munger Canyon and Loma were <br />maintained as necessary. <br />Discharge monitoring from the sediment ponds and mines are regulated by the <br />Colorado Discharge Permit System Numbers CO- 0038342 (McClane) and CO- <br />0040827 (Munger). Copies of Quarterly Discharge Monitoring Reports have been <br />provided, under separate cover, to the DRMS at the same schedule required by the <br />CDPS Permit. They are included in this report by reference. <br />McClane Creek Temporary Diversion <br />The Operator placed four wooden gabions in the McClane Creek channel during <br />1997 to ensure the channel would remain stable. The gabions were to provide a <br />solid place in the channel bottom to limit any further erosion. In 2004 a re- survey <br />was conducted and the data and inspection observations show there has been <br />significant erosion subsequent to the 1997 gabion installation. Future high flow <br />events may result in additional channel scour and side - cutting erosion. Portions <br />of the diverted channel appeared to be unstable and further erosion may be <br />likely. To alleviate this problem, the operator installed a 48" culvert ( "P ") under <br />the haul road during 2006 in order to reconnect upper McClane Creek to it's <br />original lower segment. <br />Probable Hydrologic Consequences <br />As demonstrated above, the mines had and will have a negligible effect upon the <br />hydrologic regime of East Salt Creek. The area disturbed is small, sedimentation <br />and surface water systems have functioned well for over ten years. The inherent <br />poor quality of surface water in the area is the result of site specific <br />environmental factors not from any impact caused by the mines. <br />Most storm events that have exceeded the design criteria required by the DRMS <br />have not been a problem for the system to handle. The effect that the mine has <br />on the groundwater hydrology of East Salt Creek has not been detected. <br />