Abstract: Treatment compositions and a method are provided for the removal of a plurality of heavy metals and radioactive isotopes from wastewater. The treatment compositions comprise an alkali; adsorbents, such as montmorillonite and illite clays; catalysts, such as polyelectrolytes and sodium carbonate; one or more flocculants, such as a metal salt and calcium hydroxide; zirconium as a chelating and complexing agent; and boron as a neutron absorbent. The selected composition is introduced into and mixed with the wastewater, which is then filtered to produce a sludge containing the contaminants.