Queensland's Work Health and Safety Prosecutor is considering potential charges over the Grosvenor Mine explosion in central Queensland last year.

Five workers were seriously injured in the methane explosion at the underground coal mine on May 6, 2020.

Resources Minister Scott Stewart recently told Estimates the Queensland Mines Inspectorate, part of regulator Resources Safety and Health Queensland (RSHQ), had completed its investigation into the nature and cause of the incident.

"[They've] considered over 90,000 pieces of evidence and [last week] referred its report and brief of evidence to the Work Health and Safety Prosecutor for consideration of potential charges," he said.

A spokesperson for the Office of the Work Health and Safety Prosecutor (OWHSP) said no charges had been laid in relation to the incident.

"The OWHSP aims to assess all briefs of evidence within 120 days of referral," the spokesperson said.

The move comes just over two months after the Queensland Coal Mine Board of Inquiry, set up to investigate the incident and other methane incidents at the mine, handed down its final report.

It found the mine's gas drainage systems could not cope with the rate of production.

"The gas emissions being generated by the mine's rate of production were in excess of the capacity of the mine's gas drainage system," the report said.

Agencies responding to recommendations, minister says

The inquiry made 40 recommendations, including the need for more reviews and engineering studies of mining operations.

"Resources Safety and Health Queensland continues to provide me with fortnightly updates on the progress of recommendations directed towards the regulator," Mr Stewart said.

"I note that the board endorsed improvements already underway by the independent regulator, Resources Safety and Health Queensland, and recommended that it continue to progress this work.

He said the RSHQ was working to develop a revised remuneration scheme in line with recommendations from the Board of Inquiry. 

"[This is] to ensure that it can attract and retain suitably qualified persons and incentivise inspectors to study to obtain a first class certificate of competency," he said.

"I am pleased to see RSHQ's proactive move to establish a program to support inspectors to study for their first-class certificate of competency."

It was the first time in the two months since the Queensland Coal Mine Board of Inquiry released its final report that the minister had addressed its findings in detail.

Mr Stewart said there were 47 inspectors currently employed by the inspectorate, but more were needed.

"We are still looking at filling those vacancies," he said.

Grosvenor Mine operator Anglo American has been contacted for comment.