But that's the bit that's surprising, the white dust has managed...

But that's the bit that's surprising, the white dust has managed to cover an area the size of a residential section.

As a thought experiment, a 60mm drill core used for cutting holes in jib would have 20 circles across the width of a sheet of plasterboard. It would have 40 holes along the 2400mm length of a sheet of plasterboard or 800 in total. At 10mm thick, a sheet of plasterboard could create a single stack of circles that is 60mm wide that is 8m high.

There's all the offcut's from plasterboard where as a lot of the drill material will make it into the calico bags meaning 15-20m of pegmatite drilling may only create the same amount of dust as completely crushing a sheet of plasterboard. How many sheets of plasterboard would you need to crush apart and then sprinkle over a residential section (without a house) so as to cover it with a layer of dust visible from space? I just don't see how that answer can be 1 which tends to indicate they hit something longer than 15-20m.