2010-12-17_REVISION - C1981019 (108)

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RULE 2 PERMITS Topsoil stockpile locations and extent of stripping is presented in Topsoil Handling Map (Map 28C). Annual stripping polygons are identified on Map 23B. The overall life -of -mine topsoil balance is estimated in Table 2.04.9 -16. It should be stressed that these yearly figures are estimates and can only be useful as a general guide to topsoil removal or replacement during any given year. In 2006, TR -62 was approved to modify topsoil redistribution depths. The revision also includes a requirement to annually report topsoil stockpile volumes (Volume 1, Section 2.05 "Topsoil Redistribution Plan "). This commitment to provide topsoil volumes in the annual report also applies to the Collom Revision area covered under PR -03. As TR -82 was approved in 2010, similar language allowing the replacement of variable topsoil depths has been included in this revision. All yardage and acreage figures were calculated based upon the assumption that topsoil would be removed in advance of mining activities as shown on the Mine Plan Map (Map 23B). The stockpiling of topsoil will continue until all pit development has progressed to its maximum extent. Areas available for final reclamation prior to mine closure consist primarily of backfilled pit areas. Topsoil to cover these areas will either be direct placed from areas of topsoil removal activities or topsoil will be hauled from the topsoil stockpiles. Direct placement of topsoil will be the preferred method, however, the stockpiled material will be utilized if equipment schedules, weather conditions or other operational factors make direct placement less desirable or less cost effective. After mining and regrading operations have ceased, all stockpiled topsoil will be used to reclaim the remaining pit and other disturbance areas. Topsoil will be stored in topsoil stockpiles as shown on Map 28C. Stockpiles will be constructed with outside slopes no steeper than 3H: IV. Stockpiles are specifically located to avoid erosion from wind and water and additional compaction or contamination. As can be determined from the Topsoil Handling Map is (Map 28C), all proposed stockpiles are located within stable areas. The piles will be protected from wind erosion by planting a perennial mixture as explained in Section 4.06.3 as soon as conditions allow. Proper seasons of planting will be early spring or late fall. In addition to the planted material, a considerable amount of volunteer growth can be expected to grow on all stockpiled topsoil. External erosion will be controlled through proper location of the stockpiles. No topsoil stockpiles will be placed in a drainage bottom where external erosion might pose a potential threat. Unnecessary compaction will be avoided by keeping all but essential traffic off the stockpiled areas. Topsoil signs will identify topsoil stockpiles. Contamination of the stockpiles will be eliminated by the careful selection of sites that are distant from the areas where actual mining activities are occurring. Drainage ways and areas near spoiling and blasting will be avoided where possible. 2.05.3 (6) Overburden Additional description of the removal, handling and storage of overburden material within the permit area is described under the Production Methods Section found at the beginning of Section 2.05.3. The spoil handling monitoring plan parameters for the operation can be found below. Overburden Monitoring Program Tables 2.04.6 -6 and 2.04.6 -7 summarize oberburden analyses from the Collom expansion area based on marginal and unsuitable criteria found on Table 2.04.6 -5 (WDEQ -LQD). Descriptive information regarding the exploration test boring program under sections labeled "Evaluating Geochemical Properties of Overburden" and "Exploration Test Boring Results Summary" provide additional support to the discussions below. Collom - Rule 2, Page 95 Revision Date: 1/23/09 Revision No.: PR -03