To verify the persistence of the partial saturation condition, periodic monitoring is deemed necessary by measuring the propagation speed of elastic compression waves in the soil, whose value is particularly sensitive to the degree of saturation as shown in Septic Tank Installation. Finally, periodic restoration interventions could be required if the ground becomes saturated, for this reason the injection pipes must be well protected against accidental breakage and be accessible and reusable over the years. The mixture percolates and diffuses into the soil releasing small bubbles of oxygen, which are trapped in the pores between the sand particles without disturbing