The Department of Minerals and Energy has established an expert team to investigate the wider issues raised by a tremor that killed two miners and injured 20 others at DRDGold’s North West operations in March this year, it announced on Tuesday.
It said the panel will consider the risks to mine workers, mines and the public by seismicity in mining areas, with particular emphasis on gold mines, remnant mining, pillar mining and mining districts in which mines are largely mined out and being flooded.
“The investigation team has been appointed by the chief inspector of mines in terms of Section 60 of the Mine Health and Safety Act. Dr Ray Durrheim of CSIR [the Council for Scientific and Industrial Research], Miningtek, is leading the investigation.
“He will be supported by a number of experts who will serve as assessors, as well as mine inspectors from the Pretoria, Gauteng, North West and Free State offices of the Mine Inspectorate,” the department said in a statement.
The experts on the team include pioneers of seismic research, rock engineers and seismologists. Experts in the fields of public safety in seismically active areas and hydrology will also be brought in at appropriate times during the investigation, it added.
The team will provide clarity on the following, among others:
- the risk to the public of large seismic events in mining districts and the implications for infrastructure planning and disaster management;
- whether the events of March 9 2005 at DRD North West operations can be ascribed to mining in general;
- the probabilities of repeat occurrences in the same or other mining districts, especially where the mines are mature and large areas are mined out;
- the effects of flooding and the corresponding rising water levels on the stability of faults and other geological features; and
- whether the placement of slimes and other mining discards underground can alleviate the situation.
“It is estimated that the investigation could take up to six months, with an early deadline for the completion of work anticipated to be in December 2005,” the department said.
On Monday, the department announced that an inquiry into the seismic event at DRDGold year found that the event had been triggered by strain changes in the rock mass — but the probe also revealed some other shortcomings at the mining operations.
Also, evidence adduced at the inquiry was “inconclusive to prove beyond all reasonable doubt whether it was mining induced or a natural phenomenon”, the department said.
“The inquiry also revealed the existence of a shortage of material, improper staffing, extremely long gullies, poor management control and inadequate ventilation in the gullies, which could have aggravated the consequences of the seismic events and adversely affected rescue operations.
“These irregularities will be handled by way of administrative fines and referral to the Department of Justice [and Constitutional Development] for further action,” the department said. — I-Net Bridge