iCRAG 2 year MSc Studentship: TP3.1 MSc1

Understanding the fate of potentially toxic elements in the hyporheic zone

Potentially toxic elements (PTEs) in groundwater include geogenic metals and metalloids (As, Al, Cd, Hg, Ni, Pb, Se, U, and Zn) which pose a major threat to human and environmental health across the world. In Ireland, PTEs frequently exceed World Health Organisation (WHO) drinking water guideline values in hotspots associated with Lower Paleozoic fractured bedrock environments. These thin and often vulnerable aquifers underlie over 60% of the Island of Ireland but are the least understood groundwater resource. In these systems, extended solute residence times often lead to reducing conditions and long timeframes for water-rock interactions promoting mobilisation of PTEs from geogenic sources.

There is growing interest in the role of groundwater-surface water interfaces (hyporheic zones) for transforming and attenuating groundwater pollutants transported in baseflow. This dynamic transition zone is often biogeochemically active where surface water brings dissolved organic matter (DOM) into streambed sediments. The MSc will develop a hyporheic zone monitoring network in the headwaters of a first-order stream catchment (<1 km2) where PTEs (As, Al, U, Zn) are naturally elevated in groundwater and land use is dominated by intensive dairy production. The project will investigate biogeochemical mobilisation/retention of geogenic PTEs in hyporheic zone pore water in response to DOM inputs from agricultural sources. Geochemical modelling (PHREEQC) will be used to interpret water-mineral interactions and links with Fe/Mn cycling. 3D UV-vis fluorescence spectroscopy (FEEM-PARAFAC) will fingerprint key DOM components in combination with traditional carbon system parameters such as DOC, pH and bicarbonate alkalinity. The research will address a critical knowledge gap in the understanding of environmental risks posed by DOM-mediated PTE transfers from bedrock mineral sources to stream networks via the hyporheic zone.

The School of Biological, Earth and Environmental Science, University College Cork, are seeking an MSc by Research candidate within the Groundwater Spoke of the Irish Centre for Research in Applied Geosciences (iCRAG). The successful candidate will be based at UCC and work with Dr Tiernan Henry of NUI Galway and other iCRAG researchers investigating PTE sources in Irish groundwater bodies.

Candidates should hold a second class (2.1) honours degree (or equivalent) in Earth/Environmental Science or a related discipline. Candidates should be numerate with a passion for field work and strong interests or experience in analytical chemistry, geochemistry and carbon cycling. Practical experience in UV-vis spectroscopy or geochemical modelling would be a distinct advantage. A full driving license is required for the role.

The MSc is funded for 2 years and carries a stipend of €18,000 per year plus fees. There are additional funds available to cover field work travel, chemical analytical costs and monitoring equipment. Applications must include (a) a CV, (b) a covering letter explaining your interest in the position and (c) contact details for three referees. This should be emailed as a single pdf file to john.weatherill@ucc.ie. The deadline for applications is 5 pm, March 22nd 2019 for a start date in April 2019 or later. For more information please contact Dr John Weatherill.