Disclosed is a method for treating heap leach stacks by applying an insoluble polyimide composition, such as polysuccinimide, to the surface of an ore stack and/or incorporating the insoluble polyimide composition throughout the ore stack. The insoluble polyimide composition is then exposed to an aqueous solution to initiate hydrolysis and produce one or more water soluble products, such as hydrolyzed polyimides, polycarboxylates, polycarboxylic acids and mixtures thereof that will permeate the ore stack at a concentration sufficient to suppress scale formation within the leach stack. The water soluble products may also act to suppress scale formation in piping and channels peripheral to the leach stack, thereby reducing maintenance expenses.