1991-03-20_REPORT - C1981008 (2)

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About 50 to 55 tons of waste-lime was transported by covered truck from the sugar beet factory to NucLa Mine during May 1990. The lime was applied in June over the 4.1 acres of acid mine spoil using an apron-drive manure spreader. A D9L dozer with a single four foot ripper shank was used to incorporate the waste time into the spoil. The lime application rate was selected after reviewing soil reaction, acid base potential, and sulfur fractionation data presented in the 1989 Annual Topsoil Balance and Spoil Quality Report (PCC, 1990) and suitability criteria presented in Tab 6, Attachment 6-1, Table 6-1-3 of the permit. Soil Redistribution. Soil from stockpile sites 9,10, and 13 was redistributed over 13.3 acres of final graded spoil in the Pit 2 reclamation area as shown on Exhibit 1. Soil was replaced in June and October 1990 following procedures listed in Tab 21 of the permit. Soil Thickness. A 1"=400' postmine topographic map, dated October 10,1989 was used to identify sample sites, initially in the office and subsequently in the field, at which soil thickness could be measured. Sites were located in the field by compass and by controlled pacing from readily identified reference points. Soil thickness measurement sites were selected using a 200-foot sample grid. Soil thickness was measured on November 6, 1990 after the site had been disked, seeded, mulched, and crimped. A Montana Sharpshooter was used to excavate a small, shallow pilot hole through the soil layer at each sample site. The soil/spoil interface was easily identified by an abrupt color change, texture or grain size difference, change in consistency, and/or the presence of coal, shale or sandstone chips in the spoil medium. A brief soil description was prepared at each sample site. Moist color, consistence, texture, and soil thickness were recorded. Soil thickness was determined at the 14 sample sites shown on Exhibit 1. Soil thickness information for each sample site is listed in Table 1. Information pertaining to the color, texture, and consistence of soil is contained in Peabody's files and is available upon request from the Western Division office in Flagstaff, Arizona. Soil thickness ranged from 5 to 14 inches with a mean of 8 inches. This mean soil thickness is slightly greater than the mean soil depth requirement of 7 inches presented in the approved soil reconstruction plan for Permit C-81-008 (Exhibit 21-2, Postmine Soil Replacement Depths). 2