exiting as watching twatching the grass grow., page-28

I have to feel maybe the factor of what is the grind size determines the usefullness of the tailings
The degree of grinding will determine the size the aggregate is broken down to as a silt is finer than sand and clay is finer still than silt.

If the grind size was down to the clay in aggregate size (think this is called slimes in sand mining) then the low macroporosity of the compacted clay will make it of little use for fill and is also more likely to shear from the parent material which would mean a lower angel fo repose is needed for stability.

Less ground material resulting in a larger size (guessing larger than 1mm) in size is likely to be more usefull in the construction industry.