To easily remove liquid collected in a recess for inserting a piping channel.

This underground laying structure 200 for plastic piping is provided with an earth and sand/crushed stone layer 210, a concrete layer 220, an island 110, a recess 130, a horizontal pulling pipe 230, rising piping 240 and an elbow 250. Suction piping 260 is provided downward at the bottom of a fuel supply machine 100. The piping 260 is communicably connected with the top end of the piping 240 through a plastic socket 280 and a piping joint 270 on the recess 130. The inside bottom of the recess 130 is charged with an earth and sand/crushed stone layer 280 from the above after the piping 230 and the piping 240 are connected through the elbow 250. An earth and sand/crushed stone layer 290 is filled to at least a half of the piping 240 height vertically. The top face of the layer 280 filling the inside of the recess 130 is covered with a concrete layer 300.