The interaction of poly(acrylic acid) (PAA) and poly(ethylene glycol) (PEG) with strontium ions and the binding of strontium ions by equimolar interpolymer complexes (IPCs) of PAA and PEG were studied. The stability constants of binary polymer-metal complexes were determined. Aqueous solutions of IPCs of PAA and PEG were applied as soil structuring agents in model and real experiments. The ability of IPCs to capture radioactive strontium ions from the polluted soil of the Semipalatinsk Nuclear Test Site was established.