PROBLEM TO BE SOLVED: To provide a fluorine insolubilization/stabilization treatment material which is capable of easily and efficiently stabilizing fluorine contaminated soil and fluorine contaminated ash and which is excellent in fluorine insolubilization, especially capable of maintaining the reduction effect of fluorine elution from once treated and solidified soil even if the variation of pH occurs due to the influence of acid rain and the like, and to provide a treatment method of fluorine contaminated soil or fluorine contaminated ash. SOLUTION: The treatment material includes plaster, lime, iron sulfate and a phosphoric acid compound, and further includes amorphous aluminum hydroxide and the like if needed. The treatment method is characterized by blending the treatment material with the fluorine contaminated soil and fluorine contaminated ash. COPYRIGHT: (C)2008,JPO&INPIT
