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The water quality in the Northwest Intake Pool has been met CDPS <br />discharge requirements so no treatment has been required. The water <br />quality is not expected to change so no treatment is anticipated. <br />The North Decline gravity dewatering system is the primary dewatering <br />system for the mine. The siphon will be maintained as a backup <br />dewatering system. The South Portal dewatering pipe will be abandoned. <br />As stated above the Northwest Intake Siphon has a capacity of about 220 <br />gpm. As a backup system, it will be able to handle the majority of the flow <br />if the North Decline gravity dewatering system requires maintenance due <br />to decreasing flow capacity. <br />The South Portal dewatering pipe will be plugged with concrete grout. <br />Approximately 6 cubic yards of grout will be pumped into the South Portal <br />dewatering pipe. This is an adequate volume of grout to plug <br />approximately 2,000 feet of the 4-inch pipe. The South Portal dewatering <br />pipe will be buried in the portal backfill. <br />The North Decline dewatering pipe drill was constructed as shown on <br />Figure 14-8. Design for alternative sediment control utilized is presented <br />in Appendix 14-6 beginning on page 14-6-74. Available topsoil was <br />salvaged. The drill pad development was virtually all cut. Therefore, a <br />temporary spoil pile with a capacity of approximately 2,000 cubic yards <br />was required. Topsoil and spoil were placed in stockpiles located at the <br />North Decline reclaimed is the area shown on Figure 14-8. Topsoil from <br />the footprint of the spoil pile was placed in the topsoil stockpile. The drill <br />pad was be reclaimed as soon as the dewatering pipe was operational. <br />The reclaimed area along with the area disturbed in the North Decline was <br />seeded and mulched according to the reclamation plan presented above <br />in this tab section. <br />14-30i (Rev. 08/07) <br />