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Proposed New System and Efficiencies:The new proposed Golden Wonder mine and stormwater <br /> treatment process eliminates the problems experienced with previous systems in,but not limited to,the <br /> following ways; <br /> 1. Keeps gulch water isolated,throughout the process,from all mine features by discharging it <br /> directly back into the gulch below the sump/weir sampling point.This limits monitoring and <br /> sampling to actual mine site related water with flow rates that are considerably smaller.This <br /> is more environmentally sound than allowing gulch,treated,and untreated water to mix <br /> prior to sampling and discharge. <br /> 2. Captures and retains both minewater and stormwater to limit treatment,sampling,and <br /> discharge until actually needed...determined by observable storage capacity. Based on <br /> typical flow rates(minewater flow and storm events)it is anticipated that water <br /> treatment/sampling may be required as often as 3 days per week early in the season(April- <br /> June)and tapering off to as little as once every ten days to two weeks in late summer and <br /> ultimately to nothing as flows dry up completely in September.This is a much easier system <br /> to sustain humanly and economically. <br /> 3. Eliminates the inefficiencies of treating/sampling fluctuating flows from combined sources <br /> and creates more consistent and reliable outcomes. <br /> 4. Sample collection becomes easier and less hazardous with majority of collection points on <br /> the roads and mine pad at the treatment points. <br /> System Sources&Procedures: <br /> Minewater will be captured just outside the portal and be stored in a lined(N45B), retention pond of <br /> appx 20,000 gallons in volume. (See red square area on the eastern portion of the mine pad). Mine <br /> water discharge rate varies throughout the year from up to a few gallons per minute in the spring <br /> (usually late April-mid May)to less than a tenth of a gallon per minute during the late summer and fall. <br /> At maximum three gallons per minute,a daily capture rate would be 4,320 gallons.(We have actually <br /> never experienced this high of flow rate). Fifteen thousand gallons of active storage capacity would <br /> provide over three days of storage. Later in the summer when flow rates are very low,it is anticipated <br /> that treatment and discharge may occur only once per week or possibly every other week. <br /> From the retention pond water will be pumped,as needed based on observable capacity,to a partially <br /> buried polyethylene treatment tank of appx 5,000 gallons.The location of this tank will be immediately <br /> downstream from the retention pond.There reagents(soda ash has proven to be most effective and <br /> efficient)and floc will be added,thoroughly mixed with pumps,and allowed to settle.A fifty-pound bag <br /> of soda ash will neutralize 3,200 gallons of mine water with a starting pH of 2.6.Treated water in the <br /> tank will settle over the course of 24-30 hours and then,after checking and recording the pH,collecting <br /> a sample,the neutralized water will be decanted and discharged via a 3"pipe down the existing <br /> limestone channel to a point in the lined sump/weir immediately upstream of the 0.5' H Flume where <br /> flow rate and pH will be recorded by existing equipment and,if needed,a final sample collected as it <br /> 2 <br />