Abstract: The subject invention provides a building material useable as a compressed solid or as a foamable product in building projects. The building material is formed from an isocyanate and an aggregate originally having a contaminant present therein. The aggregate has been processed such that the amount of the contaminant is below a predetermined level within the aggregate. The contaminants that may be present in the aggregate include inorganic contaminants, volatile organic contaminants, and synthetic organic contaminants. The aggregate may be obtained from reclaimed soil, reclaimed sediment, reclaimed sludge, reclaimed fill material, and reclaimed mine trailings.