[miningmx.com] — THE Department of Mineral Resources (DMR) on Friday slapped tough new technical restrictions on mechanised platinum mines just hours after chief inspector of mines Thabo Gazi denied this would happen.
Aquarius Platinum (Aquarius) announced late Friday evening that it had received an instruction from the principal inspector of mines in the North West region to reduce bord widths from 10m to 6m.
The bord width is the extent of the reef that is mined out by mechanised operations between the supporting pillars of reef left in place to hold up the roof of the workings.
The Aquarius announcement said its Marikana and Kroondal operations would be affected and added that the instruction applied to all mechanised bord and pillar mines in the North West.
Miningmx had approached the DMR on Friday morning for comment after learning of industry speculation that this specific restriction was about to be imposed.
The speculation surfaced around the safety meeting called by Minister of Mineral Resources Susan Shabangu in Pretoria on Thursday which was attended by the CEOs of 15 platinum mining companies.
Gazi told Miningmx, ” I don’t know about that. That was not part of the discussions which did include the issue of mine design but did not get into any specifics.
“We engaged at the level that mines must be designed with the best knowledge and technology available. There were no prescriptive measures on what bord and pillar sizes should be.’
According to Aquarius the instruction stated that, “all mining companies in the North West region employing the bord and pillar mining method are instructed..to immediately review the code of practice for the prevention of rockfalls and rockbursts in metalliferous mines, related mine standards and procedures to cater for more effective safety measures including but not limited to:
“Maximum mining bord width of not more than six metres; extraction ratios should not exceed 75%; supporting of prominent geological features by pillars; boxing of roadways must be towards one direction and orientation of leads and lags between headings must almost be aligned for the purposes of effective ventilation.’
The instruction added, “until such time that the aforesaid review is conducted, no headings/faces of more than six metres bord widths should be advanced for the purposes of production.
“All mines employing the bord and pillar mining method where bord widths exceed six metres must notify the office of the principal inspector of mines on their action plans to convert to more safer and conservative mining parameters.’
Aquarius commented it was assessing the impact of these instructions “which may take some time.’
The company added it was urgently consulting with government and the other mining companies affected by these instructions.
The likely impact of these radical changes to mine design will include lower production and higher operating costs.
JP Morgan Cazenove analyst Steve Shepherd commented in a research report published on Thursday that, “it is not possible at this stage to calculate the value impact that any support standard changes may have without specific disclosure from any affected miner.’
But he added, “a new, more stringent blanket support ruling would almost certainly lead to reduced extraction rates, lower efficiency, lower production and higher costs at affected mines.