MINERALOGICAL AND CHEMICAL CHARACTERIZATION OF SEDIMENTS FROM IMPERVIOUS URBAN STREETS

Abstract

This study aimed to determine the granulometric and mineralogical composition and the contents of trace elements Cr, Ni and Pb in sediments collected in impermeable streets located in the urban perimeter of Toledo PR, Brazil. The mineralogical analyses were performed by a diffractometer, the granulometric by integrated sieving methods and laser diffraction, trace elements in sediment quartered fractions by optical emission spectrometry with inductively coupled plasma (ICP-OES). It was concluded that the sediments with an average granulometric greater than 0.09 mm and finer fractions represented by the clay. The mineralogy identified ferruginous substances characteristics of Distroferric Red Latosol - DRL with high presence of quartz and diopside. Statistically it was shown that the concentrations of the trace elements in sediment samples had a significant enrichment for Chromium and Nickel in the central area’s streets and the Lead in lower concentrations in the streets of the periphery areas. The sediments have an average particle size with diameters greater than 0.09 mm, represented by sand, and the fine sediments represent 2 to 6% of samples. The software indicated that the sediments are from different anthropogenic sources. The diffractograms show peaks for quartz and diopside. The enrichment for trace elements was significant for chromium and nickel on the downtown area streets.