It is obvious, the scientific and empirical basis to delimit protection areas have to be improved and complemented. Moreover we have to see, even with a much broader knowledge of the determinating parameters we often will fail, to establish protection areas preventing wells in every case from damage. by means of some examples I would like to point out:
- The difficulties to get valuable permeability coefficients, conductivity and flow patterns as well as unequivocal and significant results of tracer tests allowing to delimit protection areas.
- The fact we don't master the propagation of harmful pollutants as nitrates, pesticides, sometimes mineral oils, too, and so on with such an area.
- The impossibility to include in protection areas the drainage basins of streams, recharching the aquifer by influent seepage.
- The difficulties in dimensioning and in taking the necessary precautions within protection areas in karstic regions.
These examples prove, to avoid damages, protection areas have to be supported by an efficient groundwater protection also in the catchment area. That asks with high priority for a better knowledge, too.
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