This invention comprises a method of dispensing water-based decontaminants from a dispenser, comprising the steps of: (a) filling one or more tanks each with respective solutions of chemicals and water; (b) pumping the solutions from the tanks in respective hoses, each of the tanks being evacuated under the urging of a respective pump; (c) mixing the solutions at a static mixer after evacuation of the solutions from the tanks to form a mixture; (d) adding water to the mixture at the static mixer; and (e) dispensing the water-added mixture onto an incident site.