A novel class of dendritic macromolecules is provided having a core, a hyperbranched structure, and a plurality of units satisfying the formula --NR.sup.2(C.dbd.O)R.sup.1, in which R.sup.1 is not a continuation of the hyperbranched structure. Methods of preparing these dendritic macromolecules are also provided, as well as methods of using dendritic macromolecules, including those described above, in separation processes or as part of in situ leach mining processes. A class of facilities for in situ leach mining is also provided.