An Automated time-Lapse Electrical Resistivity Tomography (ALERT) system has been developed for the long-term monitoring of coastal aquifers. This ALERT system has been permanently installed in the River Andarax, Almeria, Spain to monitor and manage the impact of climatic change and landuse practice on the underlying Quaternary aquifer. An electrode array, nearly 1.6 km long, has been buried below the normally dry river bed with electrode take-outs at regular intervals of 10 m. The maximum depth of investigation is about 160 m below ground level. An unmanned, permanent control station, in a secure location, allows the aquifer to be interrogated remotely from the BGS office in the UK. Volumetric geoelectric images of the subsurface can be obtained "on demand" or at regular intervals; thereby eliminating the need for expensive repeat surveys. The entire process from data capture to image on the office PC is fully automated and seamless. The ALERT technology can provide early warning of potential threats to vulnerable water systems such as over-exploitation, rising sea levels, anthropogenic pollutants and seawater intrusion. The electrical images obtained (in space and time) are interpreted in terms of the hydrogeologic features including the seawater-freshwater interface. The timely detection and imaging of groundwater changes can help to regulate pumping and irrigation schemes.

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Within the European Commission's MIRAGE II research programme, attention has been focused on the potential for natural and anthropogenic organic compounds to complex and mobilize radionuclides. As part of this study, an array of boreholes has been constructed in a shallow confined glacial sand aquifer at Drigg in Cumbria, so that in situ radio-tracer tests can be performed in the presence of organics, under controlled conditions of groundwater flow. The effect of organics on radionuclide mobility was also studied in the laboratory using batch sorption and column experiments, and the results used to predict the outcome of a field test with the Co-EDTA complex.

Measurements of groundwater head and hydraulic conductivity have been made around a fault in the Oxford Clay in order to examine the effect of a fault on the hydraulic properties of a clay and on groundwater flow. Pulse tests performed in the clays gave values of hydraulic conductivity ranging from 5 × 10 -12 to 2 × 10 -8 ms -1 . Although showing some overlap with the unfaulted clays, the hydraulic conductivity in the fault zone appears to be enhanced with respect to the adjacent unfaulted clays by up to one or two orders of magnitude. The groundwater heads in the mudrocks/clays are high compared with those in the underlying aquifers and appear to be relics from the period before major groundwater abstraction. Some outline numerical modelling suggested that both changes in fault geometry and varying fault properties could be invoked to explain adequately the measured head profiles using the traditional assumptions of Darcian flow. However, it is recognized that coupled flow processes may be of great significance in clay formations; in particular, the measured heads may result from hydraulic effects coupled with chemical and mechanical potentials.