Lithium Converters News/Research, page-48

Yes, you'd think that quite reasonably, but it depends on how it is done. Even in the sea there are differing layers of salt at different depths - salt water and "fresh" water doesn't mix thoroughly in large scale natural environments - it forms layers with one floating on top of the other. Secondly the amount of water being drawn is a tiny fraction of the entire water table so the dilution factor is likely to be insignificant. A difference of a couple of feet can be devastating to plants and wells at the surface but inconsequential to the actual total volume of water in the water table.