Atmospheric Aerosol Loading, Chemical Composition, and Modelling PM10 Concentration in Rustenburg and Klerksdorp Mining Areas of the North-West Province of South Africa

Abstract

Atmospheric aerosols emitted from Phokeng, in Rustenburg and Jouberton, in Klerksdorp mining Towns in the North-West Province of South Africa were due to the industrial activities, wind dust, transport and fuel burning. The objective of the study is therefore to collect and analyse atmospheric aerosol data in the mining areas of Rustenburg and Klerksdorp in the North West Province. The Atmospheric aerosols studies were done over a period of 4 years (from January 2008 to June, 2011 ) for measurement of particulate matter of particle diameter of 1 O micrometers (PM10) . Data collection was done by retrieval from NASA's MISR system, Cascade Impactor and drawing air through a German Ambient Dust Monitor (which measures in situ concentrations of particulate matter of various sizes). The results obtained were compared to the South African Air Quality Guidelines (2005) and the World Health Organization Air Quality Guidelines (2005). It was observed that the PM10 values for 24 hourly periods exceeded the 75 μg/m3 maximum permissible limit for the South African Guidelines in a number of instances. According to the World Health Organization Guidelines, since their maximum permissible limits are set for 50 μg/m3, it means the study results exceeded these guidelines for more periods compared to the South Africa Air Quality Standards (SAAQS). Chemical composition of the aerosols indicates presence of the following trace elements: Pb, V, Cr, Ni , Hg, Co, Cd, Se, Mn, Ba, and As. Modeling of atmospheric aerosols was undertaken. It was found that there was a good fit between the measured and the modeled values. The research results have pointed towards the possible health risks from the presence of particulate matter in the air. This study therefore offers the first documentation on atmospheric aerosol loading in Rustenburg and Klerksdorp in the North West Province of South Africa.