Soils on a Palaeo-Indian to historic sequence in one Maine locale are analyzed for chemical enrichment. To guide excavation of four discrete sites up to 4000 square meters, samples are collected in grid patterns and analyzed for pH, magnesium, phorphorus, and calcium. Concentrations of magnesium point to probable hearths to define some centers of human activity on each site. These correlate well with anomalies determined independently by magnetometric survey. Excavation of anomalies provides evidence of hearths, culturally diagnostic artifacts, but also features resulting from tree-throw and drainage variation. The phosphorus and calcium results develop definition and delimitation of activity areas, thus refining directions for further excavation. Since phosphorus and calcium concentrations result from substantial or sustained human occupation, they show promise for preexcavation differentiation of habitation sites from limited and specialized activity sites such as lithic chipping stations. Soil chemical analysis provides both a synchronic and diachronic preview of site perimeters, size, and activity areas. The consistent site definition at the Munsungun Lake thoroughfare is useful for explaining patterns as well as locating them. -- AATA