To solve a problem wherein to use earth thermal for a heat source of air conditioning and snow melting etc., an earth thermal heat pump system for embedding a heat collecting/release pipe deeply in the ground and circulating a heat exchange medium in the heat collecting/release pipe attracts attention recently, but huge cost is required for embedding the heat collecting/release pipe deeply in the ground, obstructing spread of the earth thermal heat pump system.

A tip shoe 5 made of a short pipe with a drilling cutter edge is detachably mounted to a tip of a casing 1 constituted a steel pipe and having a spiral blade 2 on the outer periphery. After the casing 1 is rotated and intruded to intended depth, the tip of the heat collecting/release pipe 11 is connected to the tip shoe 5 through inside of the casing 1. While the shoe 5 and the heat collecting/release pipe 11 are made to remain in the ground 19, the casing 1 is extracted.