Air Furnace Blast Slag (FB) (fraction 0-4 mm) and standard Portland Cement (PC) have been used to stabilize peat soil under field and laboratory conditions. Considering the inhomogeneity of a stabilized peat block it is necessary to improve a combination of different test methods to: (1) guide the selection of slag material for specific soils, (2) assure that the mechanical stability of the stabilized peat (Peat/Slag/PC) is efficient, (3) control the homogeneity of the stabilized peat and (4) assure that the chemical stability of the stabilized peat satisfies foundation and environmental requirements