Pollution of Wells.
—The water from wells is often polluted by seepage through the earth from sources that might be prevented. Fig. 123 illustrates some of the commonest sources of contamination that through carelessness or ignorance are located in the neighborhood of the family water supply. The drainage from such sources of pollution is often directed toward the well and many cases of ill-health, disease or death are the direct consequences of drinking its water. It may be readily observed, in the case of the well illustrated, that the more water that is pumped from the well, the greater will be the tendency of the water from each of the sources of pollution to reach the well.
Another common cause of contamination of well water is that of imperfect well curbs that allow the waste water or surface water to flow into the well. The area about the well should be graded to allow no standing water, and the waste should be conducted away without permitting it to collect in standing pools.
Drainage from manured fields or other places where disintegrating animal or vegetable matter may be absorbed by water is often the cause of temporary pollution, where the water is carried to low-lying wells. Wells located in low areas that receive the drainage from such places may be suspected of pollution during the spring or early summer, when during the remainder of the year the water is pure.
In connection with any water suspected of pollution, it is well to remember that by boiling the water used for drinking, its harmful properties are entirely destroyed.