Laserfiche WebLink
Reclamation Feasibility Report - Virginia Canyon <br />Historic Structures <br />There are no historic structures other than scattered debris at site #13. The wooden collar of the <br />shaft is intact. There are the remains of a loadout and several small buildings at site #14. <br />Water Quality Impacts <br />The principal water quality effect from this site is from erosion of the waste rock. Road drainage <br />from the paved road above passes through a culvert and is directed onto the two waste rock piles. <br />A water quality sample (station #25) was collected from this site during the August 2000 <br />thunderstorm. The drainage from this pile was producing a total metals load of 862 pounds per hour <br />and a dissolved metals load of almost 35 pounds per hour.. The drainage from the waste rock pile <br />was high in dissolved arsenic, zinc, manganese, lead, iron, copper and cadmium. Deep gullies <br />have been cut in both piles, but more gullying is present at site #14. <br />The waste rock analysis shows similar results to the water quality results. However, the dissolved <br />metals concentrations were much higher in the runoff than found in the leachate. Site #13 had the <br />highest total acidity of all the piles tested, and the second lowest pH. Overall, site #13 had the <br />second highest heavy metal content and site #14 had the fifth highest metal content of the 79 sites <br />sampled. Results from the 2:1 leachate analysis are given below. <br />Site #13 <br />pH <br />S. U. Total Acidity <br />m /I As <br />b Cd <br />b Cu <br />b Fe <br />b Mn <br />b Pb <br />b Zn <br />b <br />2.1 6350 6700 580 11000 300000 2600 3200 130000 <br />Site #14 <br />pH <br />S.U. Total Acidity <br />m /I As <br />b Cd <br />b Cu <br />b Fe <br />b Mn <br />b Pb <br />b Zn <br />b <br />2.5 2140 200 520 7700 290000 2300 39000 87000 <br />An erosion channel and debris around the shaft at site #13 indicates that a portion of the drainage <br />from the road above flows into the shaft. Furthermore, it appears from a debris ring around the shaft <br />that the shaft totally fills with water at times. Prior to the August 2000 thunderstorm, there was only <br />seepage coming from the adit sampled as Station DM-2. Within 48 hours of the storm, the adit was <br />flowing again. This indicates that there may be some connection between the workings of the two <br />mines. <br />Reclamation Measures <br />These two waste rock piles are over 500 feet from the nearest stream channel. The majority of the <br />waste piles that ranked 1 or 2 are near or in the stream channels. If the drainage from the road <br />above is diverted around the waste pile, the contribution from these two waste piles should be <br />virtually eliminated. It would be preferable to divert the drainage from the road above through <br />several culverts rather than the one culvert. The location for the culverts would have to be <br />investigated to avoid causing erosion of one of the other waste rock piles in the area. <br />Regardless of the reclamation method chosen, an access road will have to be cut into this site. The <br />existing road could be improved with minimal disturbance to the surrounding area, then small track- <br />mounted equipment could be used to access the top of site #14. The gullying that has occurred <br />below the piles should be repaired. A portion of this could be done with equipment, but some of the <br />work will have to be completed by hand methods because of steep slopes. <br />30