Abstract: A process is described for solution mining isolated, mechanically mined-out areas of soluble evaporite ore to recover remaining ore reserves, wherein the mined-out areas are separated from an operational mine area by barrier pillars of the evaporite ore, by drilling at least one vertical well bore from the surface to a predefined distance above the evaporite ore body, converting the drilling of the vertical well bore to a substantially horizontal well bore at a predetermined distance below the ground level, continuing the drilling parallel to and within the evaporite ore body to form a well bore one end of which is connected to the mined-out area, developing a connection from the operating mine area to the other end of the well bore, drilling an injection well from the surface into the mined-out area, injecting an aqueous solvent into the injection well, passing the solvent into the mined-out area, removing solvent enriched in dissolved evaporite ore from the mined-out area, passing such enriched solvent from

Abstract: Process for disposing of insoluble tailings that remain when solubilizing uncalcined or calcined trona in the process of producing soda ash, in which the tailings are slurried with water or waste solutions of sodium carbonate and/or sodium bicarbonate, adding an alkali metal hydroxide or alkaline earth metal hydroxide in effective amounts up to about 10% by weight of the aqueous slurrying solution, pumping the slurry into a well connected to an underground mined-out cavity with sufficient pressure to prevent build-up of tailings from plugging the bottom of the well opening, dispersing and settling said tailings in the cavity, removing a liquor from said cavity whose concentration of sodium carbonate and/or sodium bicarbonate has been increased and recovering such enriched liquor for use in the manufacture of sodium-containing chemicals such as soda ash.

Abstract: Process for disposal of insoluble tailings that remain when solubilizing uncalcined or calcined trona in the process of producing soda ash, in which tailings are slurried with a saturated or substantially saturated solution of sodium carbonate, sodium bicarbonate and mixtures thereof, pumping said slurry into a well connected to an underground mined-out cavity with sufficient pressure to prevent the build-up of tailings from plugging the bottom of the well opening, dispersing and settling said tailings and a retained portion of the solution in the cavity, removing solution from said cavity and conveying it to the surface, recovering the removed solution for recycle and slurrying of additional tailings, and adding as make-up liquor to replace the solution retained in the cavity, a saturated or substantially saturated solution of sodium carbonate, sodium bicarbonate and mixtures thereof. The preferred solution employed in this process is purge solution which is discarded from a crystallizer circuit.

Abstract: Process for disposing of insoluble tailings that remain when solubilizing uncalcined or calcined trona in the process of producing soda ash, in which the tailings are slurried with water or waste solutions of sodium carbonate and/or sodium bicarbonate, pumping the slurry into a well connected to an underground mined-out cavity with sufficient pressure to prevent build-up of tailings from plugging the bottom of the well opening, dispersing and settling said tailings in the cavity, removing a liquor from said cavity whose concentration of sodium carbonate and/or sodium bicarbonate has been increased and recovering such enriched liquor for use in the manufacture of sodium-containing chemicals such as soda ash.