QUALITY OF DRINKING WATER FROM ONE SURFACE WATER PLANT AND SIX GROUNDWATER PLANTS IN THE TOWN OF KAJAANI IN FINLAND
The quality of drinking water must be monitored continuously. Before a raw water supply is taken into use its quality must be checked very carefully, and more detailed examinations must then be made at later stages, e.g. after five years. The larger examinations in effect form a continuous monitoring programme and can reveal some astonishing facts, e.g. the existence of chlorophenols, chloroform and carbon tetrachloride in pure drinking water as happened in our investigations. These compounds should be checked continuously to avoid further increases. Chlorophenols are already widespread in the ground.