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Mr. Michael January 16, 2014 <br />AM -01 Application Adequacy Review 2 File No. M- 1990 -057 <br />3. The Applicant has stated the existing ore stockpiles will be moved upon mill start -up. Please <br />state at what point the contaminated soil beneath the stockpiles will be placed into the TSF. If <br />the contaminated topsoil will not be transferred to the TSF until final reclamation, then the <br />Applicant should specify how the topsoil will be stabilized and contained. The Division <br />recommends reclaiming the areas where ore is stockpiled soon after the ore is removed. <br />4. The Applicant has indicated the TSF will be covered with 8 inches of embankment material <br />and 4 inches of topsoil. The proposed 12 inches of material to be placed on the TSF was <br />revised from an initial 18 inches. The Division is concerned with the difficulty in establishing <br />vegetation with a minimum topsoil depth of 4 inches. Please indicate if there is any excess <br />topsoil or suitable growth material available on site which is not being used for the TSF cap. <br />5. The Operator has committed to maintaining a three foot freeboard in the TSF. In addition, the <br />Operator has demonstrated that the total volume of in- process material would account for <br />0.5% of the total TSF volume. Upon final reclamation of the TSF, the Operator has proposed <br />placing a 12 inch cap over the TSF. Please provide an explanation of how the TSF will be <br />reclaimed once the maximum capacity is reached, provided the three foot freeboard is <br />maintained. In other words, how do you intend to cap the TSF when the elevation difference <br />between the tailings and the top of the embankment is three feet and the available capping <br />material accounts for a depth of one foot? The discussion should also specify the point at <br />which tailings will no longer be placed into the TSF. <br />6. The Applicant has proposed to reclaim the TSF by placing an earthen cap over the top and <br />then seeding the cap. Please indicate what will happen to meteoric precipitation that falls on <br />top of the TSF post- reclamation. Will the water accumulate within the lined TSF? If so, is <br />there the potential that TSF could fill with water and create a seep at the ground surface? <br />7. The water sampling plan does not include a discussion of field filtering. Samples for <br />dissolved metals must be filtered in the field. Please include a discussion of the methods for <br />filtering water samples. <br />8. The Applicant has proposed to use an existing well (MW -3) as an up- gradient monitoring <br />well once it is registered with the Office of the State Engineer. In order to use MW -3 as a <br />monitoring well, its exact location must be determined. The details of the well construction <br />(depth, diameter, casing type) must be provided to the Division. In addition, the Division will <br />require a revised map showing the exact location of all ground water and surface water <br />sampling locations. Please respond. <br />9. The Applicant has agreed to construct a down - gradient well (MW -2) at the southwest corner <br />of the property boundary. The Division will consider this well to the compliance point as <br />required by Rule 3.1.7(6). Please respond. <br />10. If a monitoring well will be drilled with a mud rotary rig, then describe how the screened <br />interval will be developed so that drilling mud is removed from fractures in the formation <br />(surging, backwashing, jetting). <br />