POLLUTION OF URBAN RUNOFF WATERS BY HEAVY -METALS .1. TOTAL METAL

The metallic content (Cd, Cu, Pb, Zn) of urban runoff waters has been studied after phase separation by 0,45 mu m filtration, as well as glo bal parameters. Sequential sampling has been performed during seven im portant rainfalls in a single residential area in 1998 and 1992. A min or first flush effect has been noted. The better part of the metallic pollutants was in the particulates at quite high concentrations (Cd 5 mu g g(-1); Cu 400 mu g g(-1); Pb 700 mu g g(-1) and Zn 2000 mu g g(-1 )). A study of the multiparameter correlations evidenced strong links between COD, BOD5, Suspended Solids and Cu and Pb concentrations in th e particulate phase. Conductivity was not correlated to any parameter.