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Reclamation Feasibility Report - Virginia Canyon <br />during 1999 or 2000. This mine adit has been observed to drain occasionally following snowmelt but <br />is dry during most of the year. <br />Sampling site DM-2 is believed to be called the Lake Tunnel. Sampling site DM-2 is located on the <br />east side of the road across from the Two Brothers/Bald Eagle Mine. This mine was sampled during <br />the May 2000 event, but was only seeping the morning after the August 2000 thunderstorm. <br />However, two days after the thunderstorm, there was visible flow from the adit. It is theorized that at <br />least part of the mine drainage is due to storm flow into the shaft at mine waste sampling site #13. <br />Gullies leading to this shaft, and debris around the wooden collar indicate that water flows into the <br />shaft during precipitation events. During the may 2000 sampling event, the measured metals <br />loading from this site was slightly less than 4 pounds per day, comprised of about 1 pound of zinc <br />and 2 pounds or iron per day. <br />Sampling site DWI-13 Is know,-, as the Rattler I unnel, Idaho Tunnel and Idaho-Bride Tunnel. The <br />collapsed tunnel drains iron-rich water directly onto the mine waste pile. The Rattler Tunnel <br />generally flows throughout the year. During May 2000, the measured dissolved metals load was <br />approximately 8 lbs./day, which was comprised of about 1.5 pounds of zinc, 2.4 pounds of <br />manganese and 3.75 pounds or iron per day. Following the August 2000 thunderstorm, the flow <br />from the adit had increased by an order of magnitude, with little change in the concentration. This <br />resulted in a measured dissolved metals loading of 88 lbs./day. The majority of the heavy metals in <br />the drainage were zinc, manganese, and iron in a similar ratio to the May 2000 measurement. <br />Sampling site DM-4 is known as the Crystal Mine. Mine drainage emits from a filled stope in the <br />road drainage ditch. The crystal mine generally flows throughout the year, but flow increases <br />following snowmelt and precipitation events. Drainage from the road above flows into the mine <br />through a stope. During the May 2000 sampling event, the measured dissolved metals load was <br />approximately 1.6 pounds per day, comprised of mostly iron. Following the August 2000 <br />thunderstorm, the measured dissolved metals load was about 9 lbs./day comprised of about 1.5 <br />pounds of zinc, 1.5 pounds of manganese, and 4.5 pounds or iron per day. <br />MINE SITE CHARACTERIZATION <br />Two hundred mining sites were evaluated to determine the major mining sources of heavy metals in <br />Virginia Canyon. One of the major disturbances in Virginia Canyon is the network of roads. Road <br />drainage was not evaluated in this study. In some cases, the roads concentrate the drainage onto <br />waste rock piles. Also, mining occurred in Virginia Canyon in areas enriched with heavy metals. <br />The areas not mined also contain some heavy metals. Based upon the analysis of five soil and <br />alluvium samples, there is undoubtedly some contribution of heavy metals from non-mining sources. <br />Quantification of the non-mining related sources would require considerably more sampling and <br />modeling. If water quality data can be collected from areas with little mining, such as Delaney Gulch <br />and other small tributaries, some delineation of the mining versus non-mining sources could be <br />made. The original sampling plan allowed for collection of samples from the relatively undisturbed <br />drainages, but there was no flow from those drainages during the spring snowmelt event and the <br />summer thunderstorm event. Following heavy snowfalls, in the past, the relatively undisturbed <br />drainages have been observed to flow. <br />The 200 mining sites evaluated were prioritized as part of this investigation. The 74 mining sites that <br />were sampled were prioritized on the basis of their chemical and physical characteristics, proximity <br />to a stream course and historic erosion. The 126 mining sites that were qualitatively evaluated were <br />prioritized on the basis of their proximity to a stream course, historic erosion, and visual indicators of <br />the chemical and physical characteristics such as the presence or absence of vegetation on the <br />17