Patent Number: 
Section: claims

1. A composition, comprising:a clay composition comprising SWY-2 clay and having interlayer boundaries;a solution comprising about 15 mMol to about 200 mMol potassium chloride mixed with the clay composition;wherein the solution comprises an ionic charge concentration of about 35 milliequivalents or less;wherein the solution provides ions in at least a portion of the interlayer boundaries of the clay composition; andwherein the solution is mixed with the clay composition in a ratio of four to one (4:1) to form the composition. 2. A method for treating a surface contaminated with radiation, comprising:applying the composition of claim 1 to the surface contaminated with radiation in a thickness of between about 0.5 centimeters and about 1 centimeter;allowing the composition of claim 1 to remain on the surface contaminated with radiation for at least 100 hours; andremoving the composition. 3. The method of claim 2, further comprising treating the surface contaminated with radiation with a decontamination foam for a period of time and removing the decontamination foam prior to applying the composition of claim 1 to the surface contaminated with radiation. 4. The composition of claim 1, wherein the composition has a pH between about 4 and about 7. 5. The composition of claim 1, wherein the solution consists of potassium chloride and water. 6. A composition, consisting of:SWY-2 clay;a solution of about 15 mMol to about 200 mMol potassium chloride and water mixed with the clay composition;wherein the solution has an ionic charge concentration of about 35 milliequivalents or less; andwherein the solution is mixed with the clay composition in a ratio of four to one (4:1) to form the composition.