AbstractPollutants such as petroleum hydrocarbons are produced from various domestic,commercial and industrial sources. Releases of PAHs are increasing and automobileis one of the major sources. Pollutants from road runoff therefore pose a risk to surface waters if not managed. Sustainable Drainage systems (SuDs) design philosophy offers water management, water quality and biodiversity benefits over conventional drainage, by replicating natural systems and use cost effective solutions with low environmental impact. SuDs utilize a range of features and techniques such as source control (SC), site control and regional control. There is a need to increase the understanding of the fate of hydrocarbon pollutants in SuDs to improve designs and assess the risk posed by pollutant accumulations.
The aim of this project was to monitor and evaluate the sources, occurrence and fate of hydrocarbon pollution in SuDs and conventional/hybrid drainage systems. Multiple sites for sampling and testing were used and via extensive monitoring (18 - 24months) water and soil quality was examined. An Accelerated Solvent Extractor(ASE) was used for extracting hydrocarbons from soils and a Gas Chromatograph -Mass Spectrometer (GC-MS), was utilized to identify TPH and PAH concentrations for both water and soil samples. General water quality parameter tests were included in the monitoring to evaluate their influence on hydrocarbons.
This study showed that the most abundant PAH compounds that were found in the particulate phase of the storm events runoff were PYR, FLAN, PHE, NAP and ANTand the PAHs with higher molecular weight showed higher tendency of accumulation in soils, while the higher concentrations of lower molecular weight PAHs were found dissolved in water. In general, high variability of PAHs in SuDs and conventional/hybrid drainage systems was seen but they varied below hazardous thresholds. In addition, no significant differences were seen between SuDs and conventional/hybrid sites in terms of hydrocarbon pollution, but water quality improvements were noticed in SC SuDs and treatment trains. Finally, the source identification of hydrocarbons varied between pyrogenic and petrogenic origin according to location and the complex and dynamic nature of SuDs and conventional/hybrid sites made the evaluation of these systems difficult.
|Date of Award||2015|
|Supervisor||John Williams (Supervisor), Catherine Mant (Supervisor) & Muhammad Ali (Supervisor)|