The most common contaminants found in household water in Northumberland County were sodium, total dissolved solids, total coliform bacteria, high and low pH and lead.
Sodium concentrations above recommended levels are most likely the result of water softeners, used to remove hardness. Sodium can have negative health effects in excess levels. Total dissolved solids, or TDS, is a measure of all dissolved impurities in water, and can be made up of sodium, nitrate, or other dissolved contaminants. It is a nuisance contaminant.
Total coliform bacteria presence is an indication that surface water may be entering a well and other more harmful microorganisms may be present.
Low pH (<6.5) can occur naturally in parts of Virginia geology. Although not a concern in itself, low pH can be a driver of how corrosive the water is. Once the water enters the house it can result in metals such as copper and lead leaching into the water from plumbing components that contain these metals. High pH (>8.5) is considered to be safe, but can cause some negative side effects in excess quantities.