RIO Tinto officially launched its Hamersley Agricultural Project (HAP) last week by turning on its first pivot.
The mining company's project will use surplus water from nearby mining operations to grow hay.
Rhodes grass is being grown under irrigation using surplus water from Rio Tinto's nearby Marandoo iron ore operation.
Rio Tinto climate change, water and environment general manager Allan Jackson said the company started seeding last week and would hopefully begin cutting hay just before Christmas.
The company is planting 830 hectares and Mr Jackson said it had everything set up and would have all the pivots operating over the next six weeks.
He said Rio Tinto was expecting to cut about 30,000 tonnes of hay each year of which 60-70 per cent would be used on the company's five stations.
Rio Tinto own six stations but managed five, totalling up to 1.5 million hectares and runs 25,000 cattle.
Mr Jackson said the company was employing eight people for the HAP but would employ contractors to cut the hay.
The remaining 30-40pc of hay is expected to be offered to local pastoralists.
"The rest (of the hay) we will put on the market," Mr Jackson said.
"It would be good for the people in the Pilbara, as it will be available without the freight expense, or cost overhead which people currently experience.
"A number of people have expressed interest in it and we will write to all station owners in the area and tell them what is available and if people are interested come talk to us."
He said the company had discussed exporting the excess hay but said while it would be available domestically first, it hadn't ruled out potential export in the future.
The project will use about 20 gigalitres of surplus water a year.
The first pivot of the planned 17, was turned on by Agriculture and Food Minister Terry Redman in the East Pilbara
"This is a visionary project highlighting the enormous agricultural opportunities to be realised through collaboration with the mining sector," Mr Redman said.
"The Department of Agriculture and Food WA has worked closely with Rio Tinto to develop this project.
"Potentially, similar projects using surplus water from other mines could create an extensive agricultural sector in the Pilbara.
"As below-water table mining increases throughout the Pilbara, this will create a future source of significant volumes of water for a range of uses.
"That water represents an exciting opportunity to help grow our agriculture and food sector even further."
Rio Tinto is conducting studies into a bigger project also in the Pilbara which may include irrigated hay production and a cattle feedlot operation.
