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particles. The water then exits Pond 1 and flows into Pond 2 through a 12" steel pipe. The water <br /> level in Pond 1 can be regulated by the use of a valve located in the outlet structure so as to <br /> optimize the process. This pond is additionally equipped with a 14" steel overflow pipe located <br /> approximately 12"higher than normal operating pond levels to maximize freeboard holding <br /> capacity and to serve as an emergency overflow. <br /> Pond 2 serves as a quiescence zone to allow additional settling of remaining suspended particles. <br /> This further treated water then exits Pond 2 to Pond 3. Outflow from the pond is provided <br /> through a series of three pipes. Two 10-inch pipes are in place to handle operational flow <br /> volumes, and an additional 12 inch pipe is located as an overflow and for emergencies. Pond 3 <br /> is used as the polishing pond and as the sump for the pump plant. Pond 3 is also equipped with <br /> two 12"emergency overflow steel pipes with no valves. Any spillage from those pipes would <br /> travel to an emergency catchment basin through a rock-lined ditch. The emergency catchment <br /> area is equipped with a rock overflow channel and would be the point for water sampling in the <br /> event of discharge, as per our current storm water discharge permit (permit number CO0048971) <br /> which was activated July 1, 2016. <br /> The pump plant consists of an 8"x6" diesel powered pump that moves the wash water to the <br /> wash plant. The pump plant is designed to move up to 1,200 gallons per minute during operation <br /> through an 8"HDPE line. <br /> There are two other ponds on site referenced as Pond 4 and Pond 5. Both ponds are only used as <br /> storm water catchment and not used for process water. There is a 12" steel overflow pipe from <br /> Pond 4 to Pond 5 and any overflow from Pond 5 would enter the emergency catchment area as <br /> mentioned above. The mine site is located a topographically up-gradient distance of 1,900 feet <br /> from Pennsylvania Creek, so in the very unlikely event that any overflow from this catchment <br /> area might occur, assuming that both emergency Ponds 4 and 5 should overflow, there would <br /> still be little chance that any surface water ever reaching Pennsylvania Creek. As discussed <br /> above, there is no record that any releases of process water have ever occurred over the 140 year <br /> life of the project. <br /> Comment 6: Provide a more detailed description of the pipe and ditch system which convey water <br /> from the wash plant to the settling ponds. Include approximate dimensions of the pipes and <br /> ditches. <br /> Response: This comment has been answered in detail in the response to Comment 5, above. <br /> Comment 7: Please provide a detailed description of how water is diverted front Pennsylvania Creek <br /> for each of the diversion points. Describe all valves,pipes and pumps associated with the <br /> diversion points. Also, describe what safeguards are in place to ensure that water from Pond <br /> I or from the wash plant area cannot backflow into Pennsylvania Creek <br /> Response: The diversion from Pennsylvania Creek consists of a low dike and small sump cut <br /> into the bottom of the creek. An eight-inch diameter HDPE pipe leads out of this structure and <br /> follows the contour of the mountain to the permit area. The pipe is valved at both the upper and <br /> lower ends, so the flow can be controlled from either side. This configuration is beneficial from <br /> both an operations standpoint and also for safety. There are no pumps associated with the <br /> 3 <br />