Each type of water system has many potential sources of contamination associated with it. Surface water infiltration. No sanitary seal installed when well was originally drilled. Cross connections are present in water system. Unsealed water storage tanks.
Water tanks are accessible to insects and small animals.
Broken water mains. Use of pesticides, herbicides, and fertilizers within the protective 100 foot radius. Whenever potable water comes into contact with surface water, animals, animal feces, insects, or any other sort of contaminant, there is potential that the water will not be fit for human consumption. When water is tested for potability, it is tested for coliform organisms or nitrates. Before the well was put into operation, it was chlorinated to remove all coliform organisms, which may have been introduced during the drilling process.