PURPOSE: To inject chemicals through an injecting pipe having through holes and a sleeve valve having extrusion holes and partition plates and being fixedly fitted on the injecting pipe, by inserting the injecting pipe into a drilled hole and by uniformly filling the injecting pipe with chemicals.

CONSTITUTION: Discharging holes 2 are drilled at 90° angular intervals around the circumference of the injecting pipe made of iron or vinyl chloride. The sleeve valve 4 having extrusion holes 3 is force-fit to the circumference of the injecting pipe 1 in a manner that the holes 2 and the holes 3 do not coincide with each other. A plurality of partition plates 6 extending along the axis of the sleeve valve 4 are provided around the circumference of the sleeve valve 4 to form a plurality of sectorial sections 7. The injecting pipe 1 is inserted in a hole 10 drilled into the ground, then a chemicals supply pipe 8 is inserted into the injecting pipe 1 to inect the chemicals 13 into the ground 15 through the sectorial sections 7.