Settling Efficiency of Urban Particulate Matter Transported by Stormwater Runoff

The main purpose of control measures in urban areas isto retain particulate matter washed out by stormwater over impermeablesurfaces. In stormwater control measures, particulate matter removaltypically occurs via sedimentation. Settling column tests were performedto examine the settling efficiency of such units using monodisperse andheterodisperse particulate matter (for which the particle size distribu-tions were measured and modelled by the cumulative gammadistribution). To investigate the dependence of settling efficiency fromthe particulate matter, a variant of the evoluti onary polynomia lregression (EPR), a Microsoft Excel function based on multi-objectiveEPR technique (EPR-MOGA), called EPR MOGA XL, was used as adata-mining strategy. The results from this study have shown thatsettling efficiency is a function of the initial total suspended solids (TSS)concentration and of the median diameter (d50index), obtained from theparticle size distributions (PSDs) of the samples.