Ground
Waters
As water seeps through the earth, microorganisms as well as suspended particles are removed by filtration in varying degrees. This depends on the permeability characteristics of the soil and the depth to which the water penetrates.
Ground water brought to the surface by springs or deep wells contains very few organisms. To construct a well the nature of the soil and underlying porous strata, the nature of the water table, and the nature, distance, and direction of the local sources of pollution must be taken into consideration.
