2019-09-16_REVISION - M1994117 (2)

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pond can be started as soon as the tailings can support the weight of a small conventional tractor. This will probably be within the first two or three years of the cessation of tailings deposition. Once the former tailings pond area has physically stabilized,the surface will be leveled by grading it with a small tractor. Then the graded surface will have a two foot rock capillary barrier placed on top of the mill tailings. This material will come from the mine dump screening operation that will provide mill feed to the Gold Hill Mill. Next, the salvaged and stockpiled topsoil, and any imported topsoil, will be placed over this rock capillary barrier to a depth of between 3 and 4 inches. The same seed mixture of both native and introduced species that will be planted on the three sides of the tailings retention embankment will be used on the former tailings pond. The seed mixture will be planted at the rate of about 40 pounds per acre by hydroseeding. A Brillion grass seeder may also be used on this part of the tailings impoundment area. A wood fiber mulch may be used to protect the seedbed from wind and water erosion, and to promote better root growth. A list of the native and introduced grass species, and the quantities of these grasses that will be planted on the reclaimed tailings impoundment area is given below. Some of the grass species on this list may be deleted or substituted following the completion of the field tests that will be conducted on consolidated mill tailings. Native Grass Species Application Rate: Pounds Per Acre Mountain Mhuly 2 Slender Wheat-grass 8 Thurber Fescue 3 Introduced Grass Species Hard Fescue 4 Intermediate Wheat-grass 8 Orchard grass 6 Red Fescue 2 Smooth Brome 5 Timothy 2 The time of the year when tailings deposition finally ceases will determine the season that these grass species are planted on the tailings retention structure. These grasses will be planted in either the late fall or early spring months; depending upon how much time is available for ground preparation following the cessation of milling operations. The optimum season for seeding the prepared mill tailings is in the late fall, so that seed germination will take place in the following spring. However, if the grass seeds are planted in the early spring, they will have ample time for growth prior to the ground freezing, and the grasses will benefit from several months of precipitation. 11