CRA gets granular on how close grassroots exploration can be to an existing mine

In order for expenses of exploring a potential mineral resource to qualify as Canadian exploration expense under para. (f) of the definition of that term, they must not relate to a mine in the the mineral resource or to a potential expansion of the mine.  CRA has apparently ruled that a proposed exploration program would qualify provided (among other conditions) that the activities are not undertaken within 1.2 kilometers of the mine shaft for a former mine on care and maintenance.

Neal Armstrong.  Summary of 2012 Ruling 2011-0422761R3 under s. 66.1(6) - CEE, para. (f).