• Baseline Characterisation
• Location of hotsport areas in the Vaal Triangle Priority Area Airshed
• Identified hotspot areas in the Vaal Triangle Priority Area Airshed
• Strategy Analysis and Interventions Descriptions
• Public Participation Process

Baseline Characterisation

The final Baseline Characterisation report has been completed and submitted to DEAT. The report includes an assessment of the ambient air quality in the Vaal Triangle through an analysis of available ambient air quality monitoring data and dispersion modeling simulations. Available ambient air quality monitoring data was obtained from Government and industries in the region.  A review of the criteria pollutants, PM10, SO2, NO2, CO and O3 was undertaken for the period 2004 – 2006. Comparison was made with the relevant Vaal Triangle Ambient Air Quality Targets (based on the National Ambient Air Quality Standards).

Monitored pollutant concentrations indicate elevated particulate (PM10) concentrations over many areas of the Vaal Triangle, in particular, residential areas where domestic coal burning occurs and neighbouring major industrial operations. These elevated concentrations coincide with periods of low temperatures and stable atmospheric conditions associated with the winter months. Sulphur dioxide concentrations approach the Vaal Triangle ambient air quality targets in the Vaal Triangle. Low levels domestic fuel burning emissions and industrial emissions contribute to SO2 concentrations. Ambient monitored NO2 concentrations are low in the region. Increased NO2 concentrations are associated with the early morning and late afternoon/evening periods. These periods are associated with increased traffic volumes in urban areas as well as possible emissions from domestic fuel burning.

Predicted PM10 and SO2 concentrations in the region were indicative of significant non-compliance with the relevant Vaal Triangle ambient air quality targets. Daily PM10 concentrations frequently exceeded the target while SO2 concentrations exceeded the respective targets in the short-term. Although ambient NO2 concentrations exceeded the hourly NO2 target in built-up areas, these exceedances occurred infrequently.
Based on the predicted and measured PM10 concentrations, six hotspot areas were identified in the Vaal Triangle Priority Area Airshed (Figure 1 and Table 1).