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they correspond to the present operations area. Notations made on these samples indicate that they represent old mine spoil approximately 30 plus years old. It is most likely that these samples were collected from disturbances associated with the Peacock Mine, that operated in the Red Arrow Seam from 1933-1947. Thus, these samples most likely represent soils that had been contaminated with waste coal for approximately 32 to 46 years. It should be emphasized that these coal contaminated topsoil samples represent what can probably be considered to be samples containing a much higher level of waste coal than would be encountered using todays more efficient mining and coal cleaning technologies. Since numerous technological improvements in mining have resuRed in more efficient coal recovery, the percent of coal in these samples are probably higher than what would be expected in the refuse pile at the Southfield Mine. This point is illustrated by the data presented in White et. al. (1982) wherein they reported that some of the old refuse piles examined contained upwards of 40 percent waste coal. The estimated percent coal fines in the present Southfield Mine refuse is between 6 and 10 percent. As a general rule the sulfur content of coal is higher than that found in the waste rock (Spaite et. al. 1979), it is logical to assume that any reduction in coal content will reduce the potential for aadfication of the refuse materials. In this light, it should be pointed out that the following comparisons represent tinrorst case' conditions with respect coal contamination and acidfication of soil materials at the Southfield Mine. • A t-test comparison was made of these two groups of samples. There were 34 non contaminated and 8 coal contaminated samples in this evaluation. The resuRs are summarized in Table 4. Examination of these data reveals that the addition of waste coal to the topsoil signficanty affects a number of soil parameters. Statistically significant decreases in pH and siR were observed, while significant increases in EC, Ca, Mg, OM, NO3-N, NH4-N, Fe, Mn, sand, and Cu were detected. These changes parallel those reported for mine spoils in the Northern Great Plains. Schafer et. al. (1979) reported increases in EC, Fe, Mn, and Zn, with decreases in pH on coal spoils high in coal fragments in Montana. In North Dakota, Safaya et. al. (1982) reported that the addition of slack coal to mine sodic spoil resuRed in decreases in pH and SAR with increases in EC, OM, Ca, Mg, total N, Fe, Mn and Zn. The similarities in trends between these studies are most consistent. The changes in the chemical and physical properties of the soil resulting from the mixing of waste coal with the topsoil materials contain both positive and negative aspects. The implications of these changes can best be compared using established topsoil suitability guidelines. Changes must be considered with respect to deficiencies as well as toxicities. Unfortunately topsoil and overburden suitability guidelines place undue emphasis on elevated levels and commonly ignore the deficiency aspects of soil chemical levels. Since the CMLRD regulations at Rule 4.06.5 TOPSOIL- RECONDITIONING require that specific deficiencies must be evaluated, this • comparison will place equal emphasis on deficiencies as well as potential toxicities. The following comparison evaluates the parameters in Table 4 that 22