The Queensland Department of Environment and Science have enacted regulatory changes designed to reduce environmental and financial liability of mining projects (QG DNRM, 2017). A major change will be the requirement of a Progressive Rehabilitation and Closure Plan (PRC Plan) with mandatory content including a planning component (eg material characterisation, mine design, final landform cover designs, post closure management) and a scheduling component (eg mining and placement of all mined units over the life of mine).Material characterisation for acid and metalliferous drainage (AMD) assessment is routinely undertaken to classify deleterious mine materials with acid, saline and metalliferous drainage potential so they can be managed appropriately to reduce the potential for environmental harm (Dold, 2010; COA, 2016; INAP, 2019). The material characterisation and classification process to identify clean cover material that is required for construction and progressive rehabilitation over the life of mine is not typically addressed in sufficient detail resulting in poor environmental outcomes. Quantifying rehabilitation material physicochemical characteristics, material classes, material balances, and its availability over the life of mine will verify if it can be used immediately or may require stockpiling. Discrepancies in waste types classified via the geological block model only could have implications for the accuracy of mine planning, waste handling and management (Dominy et al, 2002). Total deposit knowledge and geoenvironmental models enable knowledge from project silos to be shared throughout a project providing a clearer understanding of the total effect of a mine on the environment (Chitombo, 2011; Scott, 2012). CITATION: Jackson, L, Maddocks, G, Long, P and Tear, S, 2019. Approach to building a geoenvironmental block model for the Walford Creek Project, Aeon Metals, in Proceedings PACRIM 2019, pp 9093 (The Australasian Institute of Mining and Metallurgy: Melbourne).