Abstract: A composition for decontaminating biological pathogens and a system and method for mixing and applying the composition to contaminated sites are presented. The composition of the invention is suitable for the decontamination of biological warfare agents, including bacillus anthracis, and is suited for wide area or large surface decontamination. In one or more embodiments, the composition includes a blend of biocides, surfactants, a basing component. In one or more embodiments, the composition additionally includes a protein and/or an enzyme. In one or more embodiments, the composition includes a foam forming material for effective application over large surfaces. In one or more embodiments, the composition is mixed on-site from a plurality of pre-mixed components to form a foam composition for application to a chemically or biologically contaminated site.