Aquifer vulnerability case studies

A number of research projects will be based on a series of case study aquifers, covering a wide range of hydrogeological and groundwater vulnerability problems. These projects will include the use of advanced data collection methods and new analysis techniques applied to existing and new data to investigate vulnerability issues. These aquifers will also provide laboratory based and modeling projects within the network with materials and data. The case study aquifers are:

a) The Chalk Aquifer, UK (lead partner Leeds) is UK’s most important aquifer. This fractured, dual porosity aquifer is under threat from agricultural fertilizers and pesticides, and saline intrusion.

b) The Ploemeur Aquifer, Brittany, France (lead partner CNRS): This fractured, crystalline rock aquifer, under threat from over-exploitation, has been studied for 10 years by the CNRS group. Further studies will build on this large body of knowledge.

c) Cremona, Aquifer, Northern Italy (lead partner Polimi): The natural springs of the Cremona Aquifer supply water for agriculture but are threatened by over-abstraction and contamination by agricultural fertilizers.

d) Bologna Aquifer, Northern Italy (lead partner Polimi) is an important source of water to this densely populated region. The lower aquifer is under threat of contamination (heavy metals and chlorinated solvents) from the upper aquifer due to exploitation.

e) Otta-Sel (Gubrandsdalen) and Melhus (near Trondheim) Aquifers in Norway (lead partner NGU): These are typical of small unconsolidated aquifers commonly exploited for groundwater in Norway. Both are at risk from contamination from agriculture, industry and settlement.

f) The Llobregat Delta Aquifer (lead partner Barcelona): This unconsolidated sediment aquifer is an important source of water for domestic and industrial use in and around Barcelona, Spain. Saline intrusion from the sea due to over-exploitation of groundwater is a serious and growing problem.

Laboratory experiments

Laboratory-based research projects will be aimed at investigating the fundamental flow and transport processes controlling groundwater vulnerability. These experiments will focus on the vulnerability issues of, and use aquifer materials from, the case study aquifers. Experiments will take place on scales from mm to metres and involve batch, column and larger sandpack set-ups, and experiments in porous and fractured rock cores. The experiments will be designed to look at the effects of aquifer heterogeneity and the influence of sorption, reaction, degradation, dissolution and precipitation, and microbial activity on contaminant residence times and transport. In these experiments state-of-the-art monitoring techniques will be used including new on-line sensors techniques (electrochemical, chromatographic methods), and X-ray and NMR imaging methods. The lead partners will be Weizmann, Edinburgh and Barcelona.

Modeling techniques

Modeling studies will be used to simulate groundwater flow and contaminant transport processes in the case study aquifers and laboratory experiments, and to quantify groundwater vulnerability on the aquifer scale. The network partners have a strong background in both the application and development of mathematical and computational models. Modeling techniques that will be applied and/or further developed in these projects will encompass a range of commercial software already accepted as industry standards, as well as state-of-the-art research modeling techniques such as fractal and geostatisical techniques for reconstructing and simulating aquifer hydraulic architecture, and numerical and analytical techniques for modeling flow and transport in complex heterogeneous media on a range of scales. Important aims of modeling projects will be to improve the understanding and quantification of vulnerability issues in the case study aquifers and to contribute towards making these advanced techniques more accessible to the groundwater industry. Lead partners in modeling studies are Weizmann, Barcelona, UPMC, CNRS and Polimi.