Under the contract, the company will be responsible for the installation of coal stackers and reclaimers at the mine.
Calibre managing director Rod Baxter said the contract was a great example of G&S’ strong market position in the Queensland coal sector.
BMA’s Caval Ridge open cut mine, located about 25km southeast of Moranbah in central Queensland’s northern Bowen Basin, is expected to produce up to 5.5 million tonnes per annum of coal by 2014.
G&S has already begun works at the mine which is expected to be completed by January 2014.
The $39.2 million acquisition of G&S, announced earlier this month, should contribute up to $160 million in revenue to Calibre in the 2013 financial year.
As well as an established relationship with BHP, G&S can list other major coal miners in Australia as clients, such as Anglo American, Rio Tinto and Xstrata.
Shares in Calibre were trading 1.7% higher at $1.21.