Byrnecut will be working on Mankarga 1 South (M1 South), one of four separate mineral resources that have been estimated for the Sanbrado gold project, which is located 90km east-southeast of Ouagadougou, the capital of Burkina Faso.
The key operational contract, worth US$110 million, has an initial term of five years, and its award follows the completion of a competitive tender process, said West African's managing director Richard Hyde.
"We are very pleased to award the underground mining contract to Byrnecut who have a long history providing underground mining services globally and have current operating experience in West Africa," he added.
Works under the mining services contract will include underground portal establishment for M1 South, decline and level development (7km), ore driving (2km & 0.2Mt) and stope production (1.3Mt), raise drilling and cemented rock back-fill.
Byrnecut group executive chairman Steve Coughlan said: "We are looking forward to partnering with West African on the exciting Sanbrado Gold project. This project will be our second site in Burkina Faso and fifth project we have operated in the West African region."
The M1 South underground will kick-off West African's mining development at Sanbrado, with portal establishment set to commence in March 2019.
The underground development will access high-grade, free-milling gold mineralisation located directly beneath the proposed M1 South open pit at approximately 120m vertical.
According to the company's June feasibility study, concurrent mining of the M1 South open-pit ore from surface and underground will accelerate cash-flow over the early years of the Sanbrado mine life.