Factory waste must be _______________ before disposing it into the water bodies?

Factory waste must be neutralized before disposing it into the water bodies. The factory wastes contain acids and so if they are allowed to flow into the water bodies, the acid will kill the fishes and other aquatic organisms. Therefore, basic substances are added to the factory wastes in order to neutralize them. An acid-base neutralization reaction occurs between acidic factory waste and added base which cancel out the corrosive effect of  acids.