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Lorencito Canyon Mine Annua[ Hydrologic MonitorirtR Re0oa - 2007 <br />Surface Water <br />For the Lorencito Canyon Mine site area, watersheds were determined for each of the major <br />named drainages within the permit azea. Each of these divides between the watershed areas was <br />delineated, and areas planimetered to determine the total watershed azea. In addition, the length <br />of each of the drainages was determined, along with the channel slope within the permit area. <br />Determination of the flow at the surface water sites was done by direct measurement with a <br />current meter or flume. <br />Springs and seeps were first surveyed in January 1996 and subsequently confirmed in an aerial <br />and ground surveys during March 1996. The first ground reconnaissance was performed by <br />transecting the property along the major drainages while examining fox evidence of springs and <br />seeps. All springs and other water bodies noted during aerial reconnaissance were confirmed by <br />ground survey prior to transfer to the hydrology baseline map. A total of 11 springs were <br />located. The location of these springs is depicted on Map 2.04.7-1. ' <br />For each of the spring locations, flow and field parameters were determined. The flow values <br />were determined by piping or channeling all the flow from the spring to a central point and then <br />diverting this flow into a container of a known volume. The time for filling the container was <br />noted and this flow measurement translated to gallons per minute (gpm). <br />Surface waters including ponds were also surveyed quarterly in 1996. Ground surveys were <br />conducted in January in coordination with the spring and seep survey, and aerial reconnaissance <br />was performed in March. All aerial data were confirmed on the ground prior to the transfer of <br />this data to the hydrology map. A total of 19 ponds were located onsite. Ponds were monitored <br />by placing a staff gauge to record water level. Depth to the water surface from the top of each <br />staff gauge was measured quarterly. Locations of all ponds are depicted on Map 2.04.7-1. <br />Water Quality <br />To determine the quality of the water within each groundwater formation, samples were <br />obtained from each well. Each well was developed by repetitive surging of the water column <br />within the well. This surging was accomplished utilizing a 3-inch Schedule 40 PVC bailer. <br />Each well was surged until turbidity within the well effluent was substantially reduced. A <br />minimum of three well volumes were removed or well production was performed until the well <br />was dry. Following this procedure, field parameters were obtained and recorded. <br />Subsequently, wells were sampled in accordance with 40CFR 136. Samples from each well <br />were obtained via a PVC bailer. Samples were preserved by cooling to 4°C and shipped for <br />receipt by the laboratory within the required holding times. <br />During each sampling event at surface water sites, flows were determined at each station. Field <br />parameters were determined either via a Hydac pH/conductivity/temperature meter, or an Orion <br />pH/temperature meter and an Orion conductivity/temperature meter at each monitoring station in <br />accordance with 40CFR 136. Each of the sampled parameters was determined by obtaining a <br />AHR-00.<JS\Mareh 10, 200J 4 <br />