THE EVOLUTION OF GROUNDWATER QUALITY IN FRANCE - PERSPECTIVES FOR ENDURING USE FOR HUMAN CONSUMPTION

France is rich in groundwater. It has many aquifers with renewable res ources which are estimated at 100 billion m(3)/year, of which 3.5 bill ion m(3), or 60% of the water used in France for human consumption, ar e withdrawn each year. This practice is justified by the often natural ly pure quality of the water and by the regularity of the resource. Ne vertheless, free aquifers, in spite of natural physical and geochemica l barriers, are not sufficiently protected from anthropic surface cont amination and when pollutants reach them, the consequences are never n egligible, be it from a sanitary, economic or natural heritage point o f view. The most extensive pollution is nitrate contamination. Nitrate concentrations have been increasing constantly over the last 30 years and in some regions have gone over the critical threshold of 50 mg/l which is the European standard, and concentrations of 100 mg/l have be en measured in some places. The gravity of other types of pollution - mining, industrial or domestic - is determined by the mineral or organ ic products involved. The cumulative effect of all of this pollution i s serious from various standpoints: from an economic and environmental point of view because aquifers contribute to the maintenance of aquat ic life, and for our natural heritage because of the long-term degrada tion of vast aquifers in some very urban and industrial regions. we mi ght, therefore, question the possible long-term use of aquifers as a s ource of drinking water.