1. The results of engineering-geological explorations during grouting were confirmed. The necessary refinements regarding the geologic structure, introduced after the excavations had been opened up, the underground excavations driven, and effected during grouting, were taken into account in the course of the work. 2. The principal cement intakes during grouting are related to the system of tectonic joints, along which the main seepage routes could be expected to form. The actual thickness of the curtain exceeds the theoretical prerequisites of modeling standards and conditions. 3. The method applied ensured effective grouting. The high pressure (40 to 45 atm) was fully justified. The adopted hole spacing and curtain arrangement in rows, ensure the specified watertightness of 0.01 liter/(min·m2). The data yielded by geophysical investigations and settlement measurements testify to the success achieved with the consolidation grouting. 4. Laboratory and full-scale investigations during the grouting work confirmed the post-grouting stability of the joint fillers against seepage. 5. The grouting results point to the possibility of reducing the volume of the work, principally, the grouting of rock behind the adit linings.