PURPOSE: To suck up mud water through a casing in a non-rotation manner by a method in which a suction pipe is inserted into a casing whose upper part is closed with a cover, penetrated into the ground, and compressed air is supplied to the opening of the suction pipe in the water-immersed region of the upper and lower parts of the casing.

CONSTITUTION: The upper end of a pipy casing 1 penetrated vertically into the ground is closed with a cover 3, and a suction pipe 4, the first hose 5, and the second hose 6 are provided by piercing them through the cover 3. The lower end of the suction pipe 4 is inserted into groundwater, compressed air is supplied to the lower end opening 7 of the suction pipe 4 through the first hose 5, and also to the upper space in the casing 1 through the second hose 6. Muddy groundwater can thus be effectively sucked up from the lower part of deep hole of about 200m long by using mechanism having no rotary portion.