In Russia, "master drillers" make a casing pipe 4-6 meters to the rock. Well, like the drills are dull and the rock doesn't require casing, and after such crap work, groundwater overflows and, as a result, the entire aquifer gets clogged. And the Chinese just work and they have results.The day laborers put up fences, where is the whole pipe, in the landlord's land there is the whole fence.