Bolivia restarts Huanuni tin mine after fatal blast

Bolivian state mining company Comibol restarted operations at its Huanuni tin mine after an explosion left at least eight workers dead and a dozen injured.

An investigation will be carried out to determine the cause of last Wednesday's blast at the underground mine, Comibol CEO José Pimentel said. The two-day shutdown cost Comibol's Empresa Minera Huanuni unit an estimated US$200,000 in lost production, according to the company.

Bolivian mining federation officials claimed the explosion was set off by thieves known locally as jukus in reprisal for tighter controls aimed at preventing mineral theft from the mine, located in Oruro department, newspaper La Razón reported.

The blast occurred in the early hours of Wednesday in a tunnel 240m underground when four trucks carrying workers were entering the tunnel, EMH CEO Guillermo Dalence said, adding workers and explosives are transported separately and at different times.

The cause of the explosion has yet to be determined, mining minister César Navarro said, adding President Evo Morales had ordered a joint investigative commission to be formed by the ministries of mining, justice, the interior and the police.

"Until we have the official report from the investigators, we can't issue a subjective opinion on whether it was an accident, bad handling or an attack," Navarro said.

The explosion adds to a host of problems at Comibol in recent years, which had to close both the Karachipampa and Vinto smelters as well as its El Mutún iron-steel company due to technical problems and falling metals prices.

Operations at Huanuni were halted by a strike in July 2017 as workers protested against the government's plans to reduce the company's workforce and charge more for electricity. Mineral theft at the mine, declared to be in a state of emergency last year, is also costing the company an estimated 2mn bolivianos (US$280,000) a month.

The blast will undoubtedly set back work on a new US$50mn processing plant at Huanuni to double processing capacity to 3,000t/d. The plant was originally scheduled to start operating in 2015.

Huanuni produced 7,084t tin in 2016, down from 7,695t in 2015, according to the company's website.