Bacteria in Water
One of the most commonly tested indicators of water quality is coliform bacteria. Coliform bacteria is a large group of bacteria found in the digestive tracts of warm blooded animals. Some coliform bacteria are harmless, and others, such as some strains of E. coli, cause disease.

Nitrates and Nitrites in Water
Nitrates and nitrites are chemical compounds often used as fertilizers, both in agricultural operations and residential properties. They are also used in explosives, as food preservatives, as coloring agents, and as corrosion inhibitors. Even though nitrates are an essential nutrient for plants, they can cause health problems for people and animals if ingested.

Radon
Radon is a naturally occurring gas caused by the breakdown of uranium and radium-containing rock deposits in the earth's crust. Chronic exposure to radon can cause or contribute to lung cancer.
Where does radon in my water come from?
As water moves through the ground, radon gas can be carried in the water to your tap. When well water is agitated at warm temperatures in the home, radon is released into the air. When you shower, bathe or simply run the tap, the radon in the water is liberated into the air, forming radon gas that can be inhaled in.