Abstract: A sled device for burying a pipe within the ground under water. The sled is arranged to be pulled over the ground and includes a blade adjustably mounted within a tower in the sled. The blade is arranged to cut a furrow in the ground as the sled is pulled thereacross and to pull a pipe, which is connected to the lower end of the blade, into the furrow. A mandrel assembly, including a cylindrical member located in front of the leading edge of the pipe is tethered to the blade to enlarge the diameter of the furrow as it is cut so that the pipe can be readily pulled therethrough. The mandrel also protects the pipe from impact by buried obstacles. The mandrel assembly is releasably secured to the lower end of the blade by a releasable means including a crank assembly.