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Colony Reclamation Cost Estimate, Update to Exhibit L Rev. Sept. 2023 small sum is therefore included for earthwork and reclamation of these 5 acres, which results in a slight overestimate of the reclamation costs. The dam materials stockpile (Area 106; see discussion Area 106) will be hauled to this area and laid up against the valley walls at a relatively mild slope until the stockpile is exhausted. It is assumed that of the 56 acres of Area 17A, half can be graded to a mild slope using the material hauled in from the nearby Dam Materials Stockpile, Area 10B. Afterwards, topsoil will be hauled in from the Upper Davis Gulch Topsoil Pile (Area 10D) until it is exhausted, and then from the Ridgetop Topsoil Stockpile (Area 12) if needed to cover the 28 acres of mild slope area in the Coarse Ore Gulch with 9 inches of topsoil. Area 17A will then be revegetated with the mixes presented in Tables E-3 and E-5. The steeper areas of this 56 acres, also estimated at 28 acres, cannot practicably be topsoiled and will be revegetated without topsoil, relying instead hydroseeding. Plant Site, Area 18 Of the 210 acres of affected area in the Plant Site, only 52 acres are basically flat and require some dozer push work to create a gently rolling topography as per page E-52 of Exhibit E of the permit. The rest are either hilly and rough or steep. For the acreage that is essentially flat, these will first be regraded in place using a large dozer to push up/push down the flat surface to remove the expansive flat lying aspect. The intention is to create in these areas numerous randomly located low hummocks and depressions about 5 to 10 feet in height more or less as described on page E-52 of the 1980 permit application. Since the entire surface of these 52 acres is assumed to be treated in this manner, the requirement on page E-52 to rip to 2 feet depth will not be necessary in these areas. Unconsolidated areas that are not flat will be ripped as described on p. E- 52 of the permit, or, depending on their surface condition, be dozer recontoured as described above. For the purposes of this estimate, it has been assumed that half of sub Area 18G's 96 acres (48 acres)will have the dozer recontouring work. Of the 210 acre Plant Site, Area 18, approximately 49 acres, specifically sub Areas 18C (Gondola site) and sub Area 18D (North Valley Fill), are too steep to recontour and too steep to spread topsoil. These areas will be hydroseeded or otherwise treated as described as on p. E-51 of the 1982 permit application. The remaining 161 acres of the plant site will require an average of 6 to 12 inches of topsoil. Following the above described surface re-contouring and ripping as described on p. E-51, an average of 9 inches of topsoil, will be hauled to the Plant Site from the Ridgetop/Northdraw Stockpile (Area 12). The regraded and topsoiled Plant Site area will then be revegetated with the grass and forb mix presented on Table E-3 on pages E-34 and E-35 and the shrub mix in Table E-5 on page E-37 of the 1980 permit application. It may also be worthwhile to consider leaving the existing flat lying surfaces of the approximately 210 acres of the Plant Site, South Valley Fill and Switchyard Fill in their current condition with their existing cover of a mixture of grass and sagebrush. A flat lying revegetated meadow may be a preferred landform or may be of some other land use. That would appear to require a permit revision which is not proposed at this time. Rather, this estimate assumes the flat lying areas will be regarded and reclaimed as described above and as laid out in the 1980 permit application. Plant Access Road (Areas 19A thru D) Page 12