The compound allows to liquidate cavities of underground workings and dolines, including those filled with water. At this, in the process of the hydrotation reaction all the water is adsorbed by the compound having the ultimate strength from 2 to 3 MPa.

After injecting to the cavity, the compound volume expands twofold. In process of the extension closed pores appear and the specific density of the compound becomes lower than the specific density of water. For this reason the compound comes to the surface, where it gets solid preserving its structure. The compound forms monohydrates using the residual water contained in the working. If necessary, the compound seals the water break.

An experiment with the compound is shown below. On the Figure 1 the compound is placed to the bottle filled with water. On the Figure 2 the compound comes to the surface and its volume increased in 2-2, 5 times.

Figure 1. Bottle just loaded with the compound.	Figure 2. Bottle after 1 hour.

The compound technology is based on the traditional backfill method. With the compound, the cavity (underground part) can be filled as from above, so from below. At this, all the water is absorbed by the compound and does not come to the surface.