How much methane do coal seam gas ponds emit?

Abstract Ponds are often used to store significant volumes of water involved in coal seam gas (CSG) extraction, but methane emissions from these ponds in Australia are not well understood. One recent review demonstrated that key drivers of methane emissions can be derived from natural water bodies, however, natural water body emissions are poor analogues for CSG-related water body emissions. Along with identifying key drivers of methane emissions, studies of natural water bodies highlighted that substantial knowledge gaps exist in relation to CSG ponds. These gaps include understanding of microbial communities and physiochemistry (including temperature) in both sediment and water column as well as pond dimensions. The absence of such information makes it difficult to predict which CSG ponds are likely to emit methane and to develop control strategies to prevent such emissions. If such data are available from a small number of ponds, modelling approach will be essential to understand total emissions from all CSG ponds in Queensland, which will be useful to inform industry, regulatory and government on emissions accounting.