OneSteel Manufacturing awarded the five-year contract for SIMEC Mining's iron ore operations.
The scope of the contract includes specialist drill and blast services across multiple locations starting immediately.
SRG managing director David Macgeorge said the win was significant for the company's mining services business.
"It demonstrates the strength of our drill and blast capability and adds another high-quality client in the desirable iron ore sector," he said.
Earlier this month, NRW Holdings subsidiary Golding secured a three-year, $600 million mining services contract with SIMEC.
SRG shares closed at 49c, valuing the company at $218.4 million.