A method of shaft sinking through water-bearing strata by injecting chemicals or liquid cement into the ground. A number of small-diameter boreholes are put down around the shaft--and about 80 ft (24 m) ahead of the shaft bottom#m-through which cement is forced by means of pumps. The cement, when set, seals the fissures and thus prevents water inflows during sinking. The method is most successful in strong fissured strata and least successful in loose alluvial deposits.