On-site Wastewater Treatment Research

Domestic wastewater from over one third of the Irish population is treated in small-scale independent systems where connection to a sewer is deemed unfeasible. In such cases, the most prevalent treatment application is the conventional septic tank system with percolation area. A series of projects, funded by the EPA, have been investigating the performance of such on-site systems on seven different sites over the past number of years. The linked projects have been looking at the breakdown of on-site effluent (both septic tank and secondary) as it percolates through subsoil of different characteristics; evaluating the performance of different secondary treatment processes (particularly sand filters and reed beds); characterizing the quantity and patterns of domestic wastewater production and; assessing the efficiency of various distribution devices.

Prof Laurence Gill

Chair of Environmental Engineering

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Laurence Gill is a Professor in Environmental Engineering in the School of Engineering, Trinity College Dublin. His research interests involve studying the fate and transport of both air and water-borne pollutants in the natural and built environment, as well as the development of passive treatment processes. Much of the work involves extensive field studies which are then used to develop mathematical models to gain further insight into the processes. Prior to joining at Trinity College in 1999, he spent several years working in the UK water industry on the design of water and wastewater treatment processes for urban populations.

Dr. Bruce Misstear

Adjunct Associate Professor

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Dr Misstear is an Adjunct Professor in hydrogeology and environmental engineering at Trinity College Dublin, and Fellow Emeritus. His recent research topics include effects of climate change on groundwater recharge, impacts of domestic wastewater treatment systems on water quality in private wells, water pollution pathways, sustainable groundwater development in Africa, and impacts of transportation options on air quality. He is currently researching the hydrogeology of Irish holy wells. Dr Misstear is the author or co-author of over 150 publications, including the international textbook "Water Wells and Boreholes" (the 2nd edition was published in 2017). Dr Misstear served as the university's first Dean of Students between 2003 and 2007, when he was involved in the strategic development of student services and accommodation services for the university's 15,000 student population.
Previously worked for 18 years as a consultant hydrogeologist, becoming head of the Groundwater Department of Consulting Engineer Mott MacDonald and a Director of the firm's Environment and Water Resources Division. Professional experience includes water resources and environmental projects in Ireland, UK, Oman, Czechoslovakia, Bahrain, Sudan, Myanmar, Saudi Arabia, Libya and Nigeria.
Dr Misstear is both a Chartered Geologist and Chartered Engineer. He was elected a Vice President of the International Association of Hydrogeologists in 2012 and served as Secretary General between 2016 and 2020. In 2020, he received the Presidents' award of the IAH. This award is given annually to a person who has made outstanding international contributions to groundwater science and to furthering IAH's mission to promote understanding and management of groundwater resources for the benefit of humankind and the environment.

Mr. Paul Johnston

Adjunct Assistant Professor

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Research Interests

Environmental Geotechnics