Foam material for bubble shielding method and bubble shield method

摘要

PROBLEM TO BE SOLVED: To perform smooth excavation while insolubilizing a contaminant, by maintaining persistence of air bubbles in air bubble-mixed soil even when using an insolubilizer including polyvalent metal salt.SOLUTION: A foaming material for a foam shield method includes an insolubilizer for insolubilizing a contaminant included in contaminated soil, and a foaming agent from which air bubbles mixed into the contaminated soil are produced. The insolubilizer includes polyvalent metal salt, the foaming agent includes an anionic surface-active agent, and pH at 25°C is 3.5 or more.