CORROSION OF STEELS IN POTABLE GROUNDWATER .1. PRELIMINARY-STUDY

Some problems have occured in heat pumps using groundwater, and we hav e found in the pumped water some bacteria able to induce corrosion (su lphate reducing bacteria, iron oxydizing bacteria...). Before we prese nt any study on the behaviour of metallic materials, we have realized a statistical study on bacteriological contamination of groundwater. W e have observed that 45% of the installation were contaminated. But no clear relation can be found between geographical location and the pre sence of these bacteria. Observation of well by immersed video camera showed a varied resistance to biofilm growth on different materials fo r casing as steels, PVC, wood, concrete... In some cases we observed a n important growth on stainless steels as AISI304L or 430 grades. Fina lly, we propose some technical possible solutions for new installation s and some prevention to do on actual sites.