Septic waste and surface water are common sources of coliform bacteria. There are numerous sources of nitrates including natural deposits. High nitrate levels are often found in agricultural areas due to fertilization of the soil. Other sources of nitrates includedecaying organic material such asis found in septic tanks. In household water, pH is used as an indicator of the corrosive tendencies of the water supply.
Acidic water is typically corrosive to any metal partsof the plumbing system.
Acidic water damages metal plumbing systems and often results in elevated levels of lead, copper, and cadmium. High pH numbers indicate alkaline water. Alkaline water coupled with a high hardnesslevel may exhibit unacceptable scaling in the plumbing system. Acceptable pH range is 6.5 to 8.5. Iron Iron - Natural waters often contain iron.