In a method and apparatus for operating and regenerating ion exchange material a wash fluid or elution solution for rinsing the ion exchange material (1) is prepared, there is collected as a by-product of said preparation a first waste stream including cationic species to be eliminated, the ion exchange material (1) is subjected to a wash step in which there is eluted from the ion exchange material by the wash fluid or solution an anionic species to be eliminated and a second waste stream including the anionic species to be eliminated is obtained, the first waste stream (12) and the second waste stream (14) are combined to form a precipitate SW comprising a reaction product of said cationic species and said anionic species, and the precipitate is removed. The method provides an efficient means of eliminating undesired species from a circuit containing an ion exchange material to be regenerated.