Anglo American’s Grosvenor boss warned of methane threat

Five days before methane exploded underground at Anglo American’s Grosvenor coal mine, a senior executive warned he was losing control of the dangerous gas.

Anglo American CEO Tyler Mitchelson arrives at the Brisbane Magistrates Court last year. Picture: Glenn Hunt

Five days before methane exploded underground at Anglo American’s Grosvenor coalmine, grievously injuring five workers, the company’s senior executive on site warned he was losing control of the situation.

“Unfortunately … the methane levels in the tailgate are ­almost to the point of bordering on unmanageable,” site senior executive Trent Griffiths told Anglo leaders in an email on May 1 last year.

The next day, he emailed again, notifying senior staff at the central Queensland mine there was a “BUCKET load of gas” underground: “We are losing the war and are at risk of losing this longwall.”

Just before 3pm on May 6, a massive methane explosion erupted underground. The five closest miners bore the brunt of the blast; their uniforms and helmets melted, and their faces, throats and lungs received terrible burns. Industry insiders say it was a miracle no one was killed.

A board of inquiry established to investigate the explosion — and other high-methane events at Grosvenor and other Bowen Basin coalmines — has heard the blast was not an isolated event.

There had been repeated incidents of dangerously high methane at Grosvenor. On longwall 104 — the section of the mine where the explosion occurred — there had been at least 14 in less than two months, not including others Anglo failed to report to the mines inspectorate.

An investigation by The Australian last year found at least 98 incidents of dangerously high methane levels were reported since 2016, when longwall mining started at the site.

Counsel assisting the board, Jeff Hunter QC, said the mining giant knew of the methane problem, as did the inspectorate, ­before the blast.

“It is at least arguable that the events of May 6, 2020, were a further manifestation of Anglo’s ongoing inability to safely manage methane at Grosvenor,” Mr Hunter said. “That senior management at Grosvenor knew there was a problem cannot be ­doubted.”

Mr Hunter said Anglo American’s own internal documents — including several emails sent by site senior executive Mr Griffiths — reveal “repeated recognition” of Grosvenor’s gas drainage to keep up with the rate of production.

“(It) raises a concern about whether production was being prioritised over safety,” he said.

On July 24, 2019, after two high-methane incidents happened within an hour and a half, an Anglo employee filling out an incident form noted that the high-gas incidents kept occurring and “design capacity cannot sustain current production rate”.

And the mine accepted — and the inspectorate knew — that there would be repeated methane breaches on longwall 104, ­because Anglo had not been able to drain one of the coal seams of gas as it had intended to do before starting mining.

By May 5 last year, the day ­before the explosion, the mines inspectorate had been warned of 14 exceedances in less than two months — including a particularly serious incident were a ­potentially explosive concentration of the gas was detected for 10 minutes. Regional inspector of mines Stephen Smith said he and the other inspectors didn’t take ­action, even though the latter event “set off alarms,” because he had an inspection of Grosvenor planned for May 13.