Abstract
M.Sc.
Emissions from domestic coal combustion account for high levels of atmospheric particulate
concentrations in Highveld townships in South Africa. These levels frequently exceed air
quality standards. To reduce these concentrations, a rollout of the “top-down” fire lighting
method, also referred to as the Basa njengo Magogo method, was introduced in a Highveld
township in Witbank, Mpumalanga, targeting 10,000 households for the winter of 2006. The
aims of this study include measuring any reduction in ambient air pollution – specifically
particulate matter (PM10) – resulting from reduced emissions due to the rollout of Basa
njengo Magogo, and to establish relationships between air pollutants and meteorological
parameters. The hypothesis of the study was that the introduction of Basa njengo Magogo
would result in a measurable reduction of ambient pollutants, specifically PM10. Continuous
measurements were made at intervals of 5 minutes from 12 July to 21 July 2006: ambient
concentrations of particulate matter carbon monoxide, carbon dioxide, sulphur dioxide,
nitrogen dioxide and hydrogen dioxide were measured as well as meteorological parameters.
Due to several factors, specifically the short period of valid measurements, this study was
not able to observe a clear reduction signal of particulate matter derived from domestic coal
burning. The air quality in the township was characterised, looking specifically at the
relationship between meteorological factors and the accumulation and dispersion of
pollutants. Investigation of diurnal variations H₂S show that minor components of H₂S are
associated with domestic coal combustion, while a source external to Vosman township
results in episodes of high H₂S concentrations. These episodes occurred between 04h00 to
07h00 and were associated with light breezes from the sector 170° to 180°. This is the first
set of quantitative measurements of H₂S in a Highveld township, and the first source
apportionment of H₂S in a Highveld township.