Laserfiche WebLink
Section 1.0 General Description of Mining Activities <br />Gold placer mining will be the primary mining activity on the site. For this mining, excavation of <br />loose gravel will take place to bedrock in a localized area. The depth to bedrock is expected to be <br />from 50 feet to 120 feet from the surface. Any material that is excavated containing higher concen- <br />trations of gold will be transported to the sluice or jig plant, where the majority of the gold will be <br />recovered. Any material that is low in gold will be treated as overburden and will be placed in the <br />mined out area from the previous cut. Gravel washed from the sluice may be delivered to stockpiles <br />for further processing in a crushing and screening plant. As shown on Map C -2, three mining areas <br />are planned for the gold/gravel excavation activity. <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 <br />pumped directly into the Plant Settling Pond. Based on past experience, this pumping rate could be <br />up to 3000 gallons per minute. As of the start of 2013, the gold recovery plant is a conventional <br />sluice plant. Gravel and fines from the plant are allowed to settle in the Plant Settling Pond, as <br />shown on Map C -2. From here, a trench is dug to the Plant Infiltration Pond, where the water will <br />either evaporate or infiltrate into the ground. <br />As mining progresses, backfilling will be done concurrently, which will restore the landscape to its <br />approximate original contour. If gravel sales grow significantly, this will still be offset by swell in <br />the mined material, which is expected to be over 20 %. The water exposure for the placer excavation <br />pit will be limited to a maximum of 9000 square feet ( .21 acres). The water exposure for the placer <br />processing plant ponds will be limited to a maximum of 18000 square feet ( .42 acres). The water <br />Gloria Z Mine 2013 Amendment 7 <br />