Since this is domestic water (drinking and bathing, etc.) i would think that people would have complained about water quality. How much of the substances you mentioned is needed to affect the SS. If so, wouldn't it be washed away into the system and out through sinks, tubs, toilets, etc...
34 story residential pump package contains 3 goulds 3-stage 20HP pumps, cla-vals, etc. The stainless steel impellers disintegrated 3 months after install. Could be debris in water? or something else... Not cavitation as the suction pressure is constant and controls would shut pumps down if...
