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