Happy livestock from surplus mine water
One of Australia’s largest potential agricultural irrigation projects is proposing to convert surplus mine water into stock feed under an innovative scheme that has now been endorsed by the Environmental Protection Agency.
Rio Tinto’s Hamersley Agriculture Project (HAP) aims to use surplus mine water from the imminent expansion of its Marandoo mine to cultivate crops for agricultural purposes and for its own pastoral leases, along with potentially on-selling to other pastoralists in the Pilbara as stock feed.
Rio Tinto general manager Climate Change, Water and Environment Allan Jackson said his team had been working closely with government agencies to progress the project, with commencement targeted for mid-2012.
“The HAP proposal provides a direct environmental benefit by reducing the discharge of surplus water into the surrounding ecosystems,” he said.
“And by establishing irrigated agriculture in the Pilbara region we can potentially increase localised stocking rates, reducing total area grazed and effectively rest large areas that may be under pressure from grazing.”
Mr Jackson said that HAP was representative of Rio Tinto’s conscious commitment and responsibility to preserve environmental values wherever possible, by not only conserving water used in operations but also putting to the best use surplus water extracted through mining activities.
The irrigated agriculture scheme involves installation of irrigated pivots over a 1650 hectare area at Rio Tinto’s Hamersley pastoral station. Irrigated pivots are commonly used in broad acre farming throughout Australia to assist in the production of crops.
The irrigated agriculture scheme will produce enough hay to feed Rio Tinto stock all year round, with a substantial excess.
A small proportion of the irrigated area will also be used for growing and harvesting of native seeds to supply the Rio Tinto rehabilitation programme across the Pilbara and potentially for other projects such as biodiversity.
Additional surplus water from Marandoo will be used to replace water currently supplied from the Southern Fortescue borefield to the Tom Price town and mine, replenishing the borefield through aquifer reinjection.