Laserfiche WebLink
Section 1.0 General Description of Mining Activities <br />The site will have sand and gravel mining, as well as gold placer mining. The primary material to be <br />mined over the life of the mine will be the primary sand and gravel. Placer activity may be more or <br />less active in any given year. For this mining, excavation of loose gravel will take place to bedrock in <br />a localized area. The depth to bedrock is expected to be from 50 feet to 120 feet from the surface. <br />Any material that is excavated containing higher concentrations of gold will be transported to the <br />sluice or jig plant, where the majority of the gold will be recovered. Any material that is low in gold <br />will be treated as overburden and will be placed in the mined out area from the previous cut. Gravel <br />washed from the sluice may be delivered to stockpiles for further processing in a crushing and <br />screening plant and sold and sand and gravel products. As shown on Map C -2, three mining areas are <br />planned for the gold /gravel excavation activity. It is likely that the sand and gravel operation will last <br />for 20 years or more, while the gold placer operation will last from 2 -5 years, depending upon actual <br />gold placer concentration and the ongoing price of gold. <br />Mining of the bank gravel will be conducted by track hoe excavator and a dozer and loader may be <br />used to supplement this machine, as needed. A ramp will be driven down to the bottom of the exca- <br />vation, to allow trucks to be loaded with the material to be taken to the gold recovery plant. The nat- <br />ural water level in the permit area will vary with location but it generally will be found at 50 -75 feet <br />from the surface. This means that the bottom of some of the mining pits will be under water. No pit <br />excavation will take place closer than 100 feet to the closest edge of the River. <br />Groundwater will either be pumped from the pit and used in the sluicing operation or will be pumped <br />directly into the Plant Settling Pond. Based on past experience, this pumping rate could be up to <br />3000 gallons per minute. As of the start of 2013, the gold recovery plant is a conventional sluice <br />plant. Gravel and fines from the plant are allowed to settle in the Plant Settling Pond, as shown on <br />Map C -2. From here, a trench is dug to the Plant Infiltration Pond, where the water will either evapo- <br />rate or infiltrate into the ground. <br />Gloria Z Mine 2013 Amendment 8 <br />