Abstract
The Macraes gold mine is in a semi-arid area and is surrounded by agricultural pasture that suffers from summer droughts. Some mine waters have elevated sulfate (>2500 mg/L) and elevated nitrate (5-20 mg/L), and treatment of these waters post-closure would be expensive. This study has trialed use of mine waters for agricultural irrigation. The trials were successful in encouraging pasture growth, although some localised precipitation of Ca-carbonates and saturation from over-irrigation caused some dieback. Summer irrigation added nutrients (S, N) to the soil, although the nutrient effects waned over subsequent winter. The irrigation approach is a potential win-win solution for the mine and surrounding farms with further long-term trials.