The drill highlights include 43.7 metres of 3.74 g/t gold from the Umwelt hinge target, where three holes tested approximately 300 metres of plunge of an iron formation.
In August, BHP had shut an acid plant following a boiler tube failure, disrupting copper processing. Underground mining at the site continued as normal.
Company said output at its Brucejack gold mine, in Canada's British Columbia, climbed 13 percent in the third quarter of the year to 92,641 ounces, compared to 82,203 ounces in the same period last year.
Since shutting down of all gold mining and exploration activities in 2016, the country has been losing both tax revenue and investors, a new report shows.