Carbon dioxide geological storage is one option to enable Australia to reach net zero.  Several carbon storage demonstration sites are undergoing feasibility studies and environmental impact assessment internationally and in Australia. Very recently CO₂ storage in the Surat Basin gained a lot of media and political attention – the QLD government has now put a ban on CCS in the geographical extent of the QLD Great Artesian Basin (and below it).  The reservoir that was being assessed is in a deep (~2300 m), brackish, unpotable part of the Precipice Sandstone. However, the broader formation is an aquifer of the GAB, therefore stakeholders were sensitive to potential environmental impacts. The previous demonstration site that underwent assessment was further north in the shallower part of the Precipice Sandstone (~1200 m). In that Glenhaven site the West Wandoan 1 well was drilled for the feasibility study, and the reservoir had fresh groundwater. This presentation details part of the experimental, modelling and field sampling components of the underlying research in the EIS, including CO2-water-rock experimental geochemical reactions, metal mobilisation to groundwater predictions, and creation of a reactive transport model.