Method for the removal of radioactive waste during in-situ leaching of uranium

In the process for the in-situ leaching of mineral values from an underground formation, wherein an aqueous solution of a leaching agent is delivered to the formation through an injection well, the solution remains in contact with the formation for a period of time sufficient to effect the solubilization of said mineral values therefrom, whereby said contact also effects the solubilization of undesirable mineral values including radium-ion containing radioactive waste, and the pregnant solution with said mineral values dissolved therein is thereafter pumped from the formation to a level aboveground through a production well, comprising a tube-like member having apertures at a lower section thereof, said apertured section having a length at least coterminus with the interval of pregnant solution which is to be pumped from said production well, whereby the radioactive waste-containing pregnant solution results in the contamination of aboveground equipment and the creation of waste disposal problems;

• an improved process, for abating said contamination and minimizing said problem of waste disposal, which comprises, substantially coterminus with the interval of said pregnant solution to be pumped from said well, interposing a sand pack between the outer surface of said tube-like member and the pregnant solution in the formation, said sand pack containing a graded size fraction of a barium containing ion exchange material in an amount sufficient to decrease the radium-ion concentration of said pregnant solution to a level which is no greater than 0.1 the level of the incoming unexchanged pregnant solution in said formation.