1990-04-27_REPORT - C1980005 (3)

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' representative revegetation sites. The nitrate analysis will also continue to be ' determined on water samples collected from Spring BP-0001 and Pond DA-0004; however, the data will only be presented in the annual Hydrology Monitoring Report. Peabody's revision request is still pending with the Division. Wolf Creek Spoil Sampling Peabody is required to sample and analyze final graded spoil from the Wolf Creek mining ' area prior to topsoil replacement. Spoil is sampled on a 300 foot horizontal grid and tested for pH, acid base potential (ABP), manganese (Mn), and soil salinity (EC). A ' selectively handled suitable spoil topdressing is made prior to topsoil replacement where acid strata (pH <5 and ABP <-5) are encountered. The monitoring program is outlined on Pages 6-153, 6-153a, 6-164, and 9-40 of the PAP. Final graded spoil was described and sampled on September 13-15, 1989 at 29 sites located ' in the Wolf Creek mining area. Spoil pits were excavated with a backhoe to a depth of 60 inches to expose the upper spoil horizons. Spoil material was described and sampled to ' profile depths which exceeded the projected plant rooting zone (about 48 inches). Field soil properties, including color, rock type, rock fragment content (volumetric), degree of compaction, and texture, were described by using methods presented in Soil Taxonomy (USDA-SCS, 1975) and Soil Survey Manual (USDA-SCS, 1951 and 1962) including revised Chapter 4 - Examination and Description of Soils in the Field (USDA-SCS, June 1981). Spoil sample increments varied from 1 .0 to 4.0 feet based upon visual differences in color, texture, rock type, and rock fragment content. The sampled spoil material was placed in clean, labeled, 4-mil thick polyethylene storage bags and was kept cool and dry to limit chemical changes. The samples were shipped on September 15 to Inter-Mountain ' Laboratory (IML) in Farmington, New Mexico for analysis. The soil analyses methods are listed in Table 2. ' The location of each spoil pit is presented on the enclosed 1"=400' scale existing topography map (Exhibit 1 , Topsoil and Spoil Monitoring Map - 1989 Field Season). Coordinate and elevation data, provided by the Seneca Mine Engineering Department, and field description data are presented in Table 3. Laboratory results ' for spoil samples collected from the 29 Wolf Creek mining area backhoe pits are presented in Table 4. Sixty-five percent of the area had been topdressed (subsoiled) before sampling. 3 PEABODY COAL COMPANY Western Division