Laserfiche WebLink
Colony Reclamation Cost Estimate, Update to Exhibit L Rev. Sept. 2023 <br /> existing flat surface areas on the Bench. Since it expected to be coarse rock it will not <br /> require revegetation. The plateau access road crosses over the Mine Bench at its upper <br /> and lower ends. This roadway needs to be maintained as a permanent landform. Other <br /> than the above described open channel cut with its two culvert crossings and the work <br /> on the Mine Bench Flume, there are no other reclamation work planned for the Mine <br /> Bench. See Figures L-2 and L-3. <br /> Summit Office Site, Area 8B <br /> This 6 acre flat lying gravel paved site was the site of Summit Construction Company <br /> office and yard during construction of Middle Fork Dam in 1981/82, then an earth and <br /> rockfill embankment dam design. It is on the ridgetop between Davis Gulch and Middle <br /> Fork Valley, along the Dam Access Road (Area 8A) which as deemed completed <br /> permanent construction and released from reclamation requirements in the 2007 Partial <br /> Acreage Release AR-01. <br /> The Summit Ridge office site is used today as a convenient site overlook, from which the <br /> entire Plan Site (Area 18), Coarse Ore Valley (Area 17), LaSal Laydown Area (Area 16), <br /> the Ridgetop Topsoil Stockpile (Area 12) can all be seen from a single vantage point. <br /> Further, the site is used at least once per year as a staging area for maintenance work <br /> related to now permanent Middle Fork Dam. <br /> Given that Middle Fork Dam is a permanent post-mining feature, a reasonable case <br /> could be made that this area should be left as-is, with its current flat lying gravel surface. <br /> However, for the purpose of this reclamation bond estimate it is assumed it will be ripped <br /> and regraded to remove its current flat lying aspect, then re-topsoiled and seeded it as <br /> generally described on Page E-52 of the original permit application. For these reasons, <br /> at some future date, Colony will probably petition to remove this from the disturbed <br /> acreage, but that is not the assumption for this reclamation cost estimate. <br /> Davis Gulch Dam Site, Area 9 <br /> This 26 acre area encompasses the existing Davis Gulch Cofferdam which currently <br /> serves as a sediment control pond for the Davis Gulch Drainage area and a source of <br /> water for dust suppression on the upper plateau roads. It is basically the cofferdam that <br /> was built in 1981 to allow construction of the much larger Davis Gulch Dam for runoff <br /> control from the future spent shale disposal areas immediately upstream. The cofferdam <br /> was upgraded in 1983 to include a downstream stabilizing berm and an emergency <br /> spillway. It is viewed by the State Engineer's Office as a NPH dam (no public hazard). <br /> Colony has adequate absolute storage rights for this small impoundment. <br /> In view of the above, it is assumed that this facility can be left in place to serve as an <br /> upstream wildlife watering hole as well as a source of water for road watering on the <br /> upper access roads through Colony to the top of the Roan Plateau. <br /> Area 9 also includes the areas downstream of the existing Davis Gulch Dam. These <br /> areas were stripped to bare rock in 1982 for the foundation of the full size Davis Gulch <br /> Dam. They are essentially bare rock in which the dam core and upstream and <br /> downstream shells would have been placed in 1983. While these areas could be <br /> backfilled and attempts could be made to revegetate them, the slopes would be very <br /> steep, too steep for topsoil, as the backfill would be nearly angle of repose. As such <br /> they would be they would be difficult to revegetate. However, these areas present less <br /> of an environmental impact in their current bare rock condition than they would if they <br /> Page 8 <br />