Quantifying the air quality benefits of a waste collection offsetting intervention in the Vaal Triangle Airshed Priority Area (VTAPA)

Abstract

This paper presents the first-of-its-kind quantification of air quality benefits from a waste collection intervention in South Africa, using South African-based emission factors and dispersion modelling. Air pollutants are released from the open burning of unrecycled municipal solid waste (MSW). This study focused on waste collection in the Zamdela township, Sasolburg, within the Vaal Triangle Airshed Priority Area (VTAPA), using emission factors published by Wang et al. (2023) and waste collection quantities over 3 years from 2018 to 2020. Emissions from the waste skips were simulated in the CALPUFF dispersion model to assess impacts on air quality within the ambient environment. Several dispersion modelling scenarios based on different receptor configurations (i.e. ring, regular gridded and discrete) were investigated. From the total mass of waste collected over the period (13,798 tons), average emission rates of 3.27 tons of SO₂, 25.04 tons of PM₁₀, and 23.66 tons of PM_2.5 were calculated using the applied emission factors. The ring receptor configuration generally predicted higher ambient concentrations for all pollutants over the various averaging periods. This study highlights the benefits of the waste collection offsetting intervention for ambient air quality.