AGE was originally involved at Kidston undertaking groundwater aspect for the site closure strategy. More recently however AGE have been involved looking at the use of the Kidston pit (Eldridge and Wises) voids as balancing storages in a hydro-electric scheme. The model development involved updating the previous model generated for the site to MODFLOW SURFACT. This steady state model was then used to assess operational constraints (water levels in the pits) to see if there were potential impacts to the surrounding groundwater regime. The work was undertaken for Entura Hydro Tasmania for their client Genex Power.