ONE of the world's leading mining companies, Rio Tinto, has proposed a project to sell stock feed to northern WA pastoralists.
The company plans to use surplus mine water from its expansion of the Marandoo mine, near Tom Price, to cultivate crops and grow pastures as parts of its Hamersley Agriculture Project (HAP), one of Australia's largest potential agricultural irrigation projects.
Rio Tinto has pastoral leases on four pastoral stations throughout the Pilbara with another sub-leased, including the Hamersley station, which was chosen for the integrated scheme due to its closeness to the Marandoo mine.
The stations graze between 20,000 and 30,000 cattle at any one time.
Rio Tinto climate change, water and environment general manager Allan Jackson said Rio Tinto had been working on the project with government agencies and was aiming for a starting date in mid-2012.
"The HAP proposal provides a direct environmental benefit by reducing the discharge of surplus water into the surrounding ecosystems," Mr Jackson 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."
The project has been endorsed by the Environmental Protection Agency and is awaiting final approval from the Environment Minister, Bill Marmion.
The irrigated agriculture scheme involves installation of irrigated pivots over a 1650 hectare area at Rio Tinto's Hamersley station.
The irrigated agriculture scheme will produce enough hay to feed Rio Tinto's stock year-round, with excess to on-sell.
A small proportion of the irrigated area will also be used for growing and harvesting native seeds to supply the Rio Tinto rehabilitation program.
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.
The Southern Fortescue borefield has provided drinking water to Tom Price town for more than 40 years.
This new integrated scheme will replace water supply and assist with the replenishment of the aquifer underlying the borefield.
Water supplied from the Marandoo below water table deposit will comply with Australian Drinking Water Guidelines.
Agriculture and Food Minister Terry Redman said the research project in the Gascoyne had been trialling the use of surplus water from mine dewatering to irrigate pasture for livestock.
Mr Redman said if the model was adopted more broadly by the mining industry, it could significantly boost irrigated agricultural production in the north of the State.
It is estimated up to 200 billion litres of surplus mine water will be available each year in the Pilbara.
By comparison, the horticulture district in Carnarvon uses about 10 to 12 billion litres a year.
"The production prospects if such a large amount of water can be harnessed are enormous," Mr Redman said.
"The State Government is supportive of innovation which helps create new secondary industries, regional development and indigenous employment opportunities.
"As iron ore mining in the Pilbara continues into the future, agriculture provides a unique environmental solution to the predicted large volumes of water to be discharged."