Adenosine triphosphate (ATP) was extracted from soil samples collected from six study plots at Colstrip, Montana. Correlations were performed to relate ATP concentrations to core sample depth and to compare native range soils to spoils. ATP concentrations varied with sample depth, having concentrations greatest in the surface depths and lowest in the deepest depths. Native range soils contained higher concentrations of ATP than did the spoils. Native range soils were significantly different from spoils not only in the amount of ATP they contained, but also by the distribution pattern of ATP found in the sample core. Therefore, by comparing ATP measurements, it was possible to differentiate the two soil systems.