Once the ground has been raised to the next level, the crew can install the draining pipe. This agricultural drain, is about 10cm in diameter. However, unlike normal pipe, it has holes in it so that the water can seem in, and then flow away.
Instead of putting it in up front (which hinders the movement of the digger), we are instead installing it afterwards by digging a trench, placing the pipe and filling it back in.
Each drain pipe crosses the entire HBA array and deposits its water off the southwest face of the mound.
Photos: D. McKay-Bukowski