The CatchmentCARE team has been helping with the ‘Source to Tap’ project in the Derg Catchment in Donegal and Tyrone to get a better understanding of how the herbicide MCPA is getting into local rivers. Two groundwater-monitoring stations are to be installed in the region, but the type of geology there makes it difficult to know where would be a good place to drill the boreholes.
British Geological Survey and geophysicists from AECOM employed Geophysical techniques to help identify ideal locations to site the boreholes. This was achieved by applying a very low voltage electrical current to the ground. Electrodes along a cable detect the received current which can be used to determine how conductive or resistive the ground is enabling different zones to be found within the rock.
Overall, the geophysics survey has proved extremely helpful, which should mean that there will be much less apprehension during the drilling. However, we will not fully know how effective these surveys have been until the boreholes are drilled, completed and tested.