The capacity of drinking water abstraction wells, which is the yield for a given drawdown of the water level, is often decreasing after a certain time of operation. This well ageing can be caused in carbonate aquifers by a chemical process : calcite precipitation. Using an hydrogeochemical model developped during the internship, the quantity of precipitated calcite and the time required to fill up the bore are estimated. It is then showed that carbonate precipitation is enhanced by chemical and physical parameters (hydrogenocarbonate concentrations, temperature) as well as the operating of the well (pumping and resting).
Determination of the carbonate scaling potential of drinking water abstraction wells from hydrochemical data using hydro-geochemical modelling software PhreeqC