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• Fifteen randomly selected, geographically distributed locations at the Yoast Mine were sampled for regraded spoil. Three sites (YGSOS-16, 17, and 18) were from the "south azea". Seven sites (YGSOS-19, 20, 21, 22, 23, 24, and 25) were from the "southwest azea". The remaining five sites (YGSOS-26, 27, 28, 29, and 30) were from the "central north-west azea". Each of the fifteen spoil samples was a composite of the upper two feet of regraded spoil material at their respective sample locations. The samples were sent to IML for standazd analysis. The samples were numbered YGSOS-16 through YGSOS-30. The attached map shows all Yoast Mine regraded spoil sample locations. 2.0 METHODS Each area to be sampled was delineated on a recent Seneca Coal photobase map. All sample locations were randomly selected and geographically distributed across each azea. All locations were sampled by rile spade and soil auger. A composite sample of the appropriate depth interval was collected at each location. Samples were screened in the field over a No.10 (2mm) screen to remove hard rocks. Sample depth was noted for each location as well as other information if pertinent. Soii backhoe pits were located and dug to at least five feet by Seneca Coal. In addition to soil sampling, a complete soil profile description was completed by Jim Nyenhuis at each backhoe pit location. Soils description followed standazd Natural Resources Conservation Service (NRCS) field methods (Schoeneberger et.al., 2002}. Digital photographs were taken of each pit and adjacent landscape. All soil and spoil laboratory data was reviewed and approved by IML soils laboratory supervisor Ms. Joey Sheeley. Jim Nyenhuis also reviewed the data and requested several reruns for confirmation purposes. All soil and spoil samples were analyzed by IML. The analytical parameters included: pH; saturation percent, electrical conductivity (EC); sodium adsorption ratio (SAR calculation from meq/L for calcium, magnesium, and sodium); texture (percent sand, silt, and clay - by hydrometer method), and nitrate-nitrogen (ppm). In addition, all samples were analyzed for acid-base potential (ABP) which included separate analysis/calculation for: total sulfur percent, total sulfur acid-base (tons/1000 tons), neutralization potential (tons/1000 tons), and total sulfur acid-base potential (tons/1000 tons). Boron was not tested in 2005. All field and laboratory data were evaluated for suitability based on standazd threshold values for significant pazameters, primarily EC, SAR, and AB potential. References for suitability evaluation included "Criteria for Evaluating Overburden, Underburden, and Regraded Spoil Suitability" (Seneca Coal IIW Mine, Table 6-3, revised January 2002), and "Criteria to Establish Suitability of Topsoil, or Topsoil Substitutes, and Overburden" (Wyoming Department of Environmental Quality, Tables I-2 and I-4, November1996). Unsuitable values include pH (<5 or >9), saturation percent (CLS or >85), electrical conductivity (EC>12), sodicity (SAR >]8 or 22 depending on texture), and nitrate- nitrogen (>60ppm). Ciay, sandy clay, or silty clay texture with greater than 50 percent 2