Dept. of Civil, Structural & Environmental Engineering
The impact of on-site wastewater effluent on karst springs.
Keywords:On-site domestic wastewater treatment systems; on-site wastewater effluent contaminants; groundwater pollution; karst springs; chemical and microbiological fingerprinting; rare earth element signatures; water quality.
The domestic wastewater of approximately one third of the population in Ireland (~500,000 dwellings) is treated by on-site domestic wastewater treatment systems (DWTSs). The potential impacts of such on-site effluent are the pollution of either groundwater and/or surface water. Karst aquifers, one of the most important drinking water resources on the planet, are highly vulnerable to pollution. Considering the large number of DWTSs in Ireland and the fact that roughly 50% of the country is underlain by Carboniferous limestone, it is important to determine the impact of the pollutants from a human on-site wastewater sources on groundwater quality.
This research project primarily investigates karst springs in Ireland with the objective to characterise the diffuse recharge from domestic wastewater treatment systems effluent. Consequently, this will increase scientific understanding of groundwater pollutant contamination problems and linked risks to human health from such sanitation systems. Detailed assessment of several springs representative of karst networks of different scale and morphometry will be carried out in order to determine the contribution of on-site effluent contaminants by the use of chemical and microbiological fingerprinting methodologies. In addition, apart from the traditionally used indicators, the research project will monitor concentrations of various human-specific on-site wastewater constituents of concern in groundwater that will allow the quantification of on-site wastewater contribution to karst groundwater systems. Several novel techniques will be tested as a part of this project in order to assess the magnitude of human impact on groundwater quality.
The research is conducted within the framework of the Irish Centre for Research in Applied Geosciences (iCRAG). iCRAG is funded under the SFI Research Centres Programme and is co-funded under the European Regional Development Fund and by iCRAG industry partners.
Project Supervisor: Prof. Laurence Gill
Project Co-Supervisor: Dr. Catherine Coxon