Following the project, it is hoped that this methodology and mapping procedure can be applied to a wide variety of sites and industries, identifying and visualising dust dispersion in these areas.
Knowledge Transfer Partnership
The Knowledge Transfer Partnership between DustScan Ltd, Grundon Waste Management Ltd and the University of Portsmouth, was established in 2007. The aim of the project was to develop an empirical dust dispersion model and to map emissions from a hazardous waste landfill site.
19 sticky pad directional dust monitors were placed on and around the landfill site, between the source of the hazardous material and the potential receptor. Two PM10 monitors, on site, and off site, were also used. Directional dust was sampled over two week intervals. The samples were scanned and analysed with DustScan software to determine directional Absolute Area Coverage (AAC%) and Effective Area Coverage (EAC%).
The sticky pad samples were further analysed with inductively coupled plasma-mass spectroscopy (ICP - MS). Segments of each sticky pad were selected for further analysis, based on direction of interest (i.e. the hazardous waste landfill). Samples underwent digestion in strong acid, before analysis by ICP – MS.
The results provided by the ICP-MS underwent rigorous data handling procedures, which allowed the construction of mixing model plots based on four specific elements, (Mn/Pb and Ca/Fe), and the ratios between each pair. By comparing the elemental ratios from the sticky pad samples to the ratios of background soils, and the target hazardous material, it was possible to calculate the proportion of the hazardous material in any given sample.
Two other techniques, both statistical, were also used to determine the proportion of the hazardous material within each sample, based on the sample geochemistry. By using more than one method, a more robust understanding of proportion of hazardous material in each sample can be gained.
Following the derivation of proportion of each method, a map was constructed showing dust proportion at each of the 19 monitors, and thus allows a visual interpretation of dust movement on and around the site. These maps are constructed using robust geostatistical methods such as semi-variography and kriging.