Permeation or slurry grouting utilizes pressure to force grout material into seams, voids, joints, cavities or fissures in permeable earth materials or other loose soil or rock formations. Generally, the permeability is reduced by filling void spaces and in certain cases the formation is strengthened by the grout. This type of grouting utilizes a fluid grout which is highly mobile within formations and therefore travels through the void spaces without providing any significant compaction or densification of the surrounding soils. Typically, under high injection pressures, hydro-fracturing of the soil matrix will occur.