MAR In-situ Assessment

MAR potential maps provide a first-pass on MAR feasibility based on suitable landscape, (hydro)geology, and source water availability. Upon identification of suitable locations for MAR application, the following steps should be performed to ground-truth remote-sensing data and further assess MAR feasibility. 

Sediment samples should be obtained from the candidate aquifer at frequent depth intervals and analysed in the lab in order to assess the geochemical reactivity of the aquifer. Aquifers containing highly reactive sediments should preferably be avoided as they may have negative implications on the quality of the recharged water. Depending on the planned MAR scheme, sediment samples can be obtained during the installation of injection and observation wells. 

Native groundwater samples should be collected and analysed in order to obtain a complete picture of the hydro-geochemical conditions in the aquifer. Source water samples should also be analysed to assess the chemical compatibility between the candidate aquifer and the source water intended to be artificially recharged and assess the reactions which may alter and compromise the quality of the recharged water. 

Finally, reactive transport modelling can be a valuable tool assisting in identifying and quantifying the hydro-geochemical reactions and evaluating their temporal persistence. 

IGRAC can assist carrying out these steps and can provide expert advice on the chemical compatibility between source water and candidate aquifers and on the selection of the most suitable MAR scheme depending on the local geochemical conditions.