Abstract
M.Sc.
The evaluation of population exposure to air pollution is a fundamental reason for
management and control of regional air quality. The purpose of this study was to
determine the exposure of the local population to PM-10 emissions from sources
within the Vaal Triangle using a Geographic Information System (GIS). The emission
inventory compiled by van Nierop for the calendar year of 1992 (van Nierop, 1994)
was used as input data for these calculations. The Industrial Source Complex
Short Term Model (ISCST) was applied for dispersion calculations of annual PM-10
emissions. The ReGIS package was applied to determine the applicability of GIS as a
management tool. Annual average PM-10 concentration contours were calculated for the different air
pollution source groups within the Vaal Triangle. The combined source group
resulted in the highest population exposure from annual average PM-10
concentrations. Population exposure from high- (> 200 m), medium- (10 to 200 m)
and low- (< 10 m) elevation air pollution source groups were determined. The
medium-elevation source group resulted in high population exposure followed by the
low-elevation source group. The high-elevation source group had very low population
exposure as a result. The population exposures from all the industrial sources within
the Vaal Triangle were calculated and found to be very high. Annual average PM-10
concentrations from domestic fuel combustion sources were surprisingly low,
resulting in low population exposure.
ReGIS was found to be inadequate for the task and is not recommended for further
use. Despite this, GIS was found to be a powerful decision-making tool and other GIS
software packages should be explored for future research.