- Miners attribute the tremors to flooding shafts
- Tremors crack houses
- Government sends experts to investigate
SELIBE-PHIKWE: Residents in Selibe-Phikwe are living in fear of earth tremors that have been happening regularly since the beginning of the year.
These earth tremors according to the residents are similar to the ones felt during underground blasting activities when the mine was still operational. What brings panic and fear to the residents is that these tremors are happening three years after the closure of the mine, raising fears that the town might be at risk of a major earth quake in the future. Furthermore residents are alarmed by the increasing severity of the tremors.
Phikwe resident Phemelo Nthwane who resides at Newstands said that some houses are already cracking in their location. “These tremors happen almost every day, in the morning and afternoon. It just happened a few minutes ago. What worries Selibe-Phikwe residents is that no one is coming forth to explain what is really happening or what could be the cause,” Nthwane said.
While the root cause of the tremors is still unknown one of the Care and Maintenance staff at the mine told Botswana Gazette that the tremors might be caused by flooding shafts. “I want to rule out speculation that suggests that these tremors might be as a result of electricity sub-stations left in the mine. All sub-stations have been removed. These tremors could be as a result of flooding shafts because when the mine was operational this underground water was pumped outside to avoid flooding of the shafts which could result in rock falls and subsequent tremors. Following the downsizing of the support staff, the shafts started flooding because there are no longer people who are responsible for pumping the water outside,” one of the support staff explained.
Another resident Manabala Manabala explained that when the tremors started in December last year he only thought of the gum poles that supported underground rocks. “These supporting gum poles were changed monthly but since there are no workers there they might have been affected by water and reached their lifespan because of effects of water and collapse. Once they collapse, the rocks will also fall. So I am not sure if I can say that our town is in danger, but it might be more so that the mine is non-operational,” observed the BCL location resident.
Former miner Joel Modise further suggests that the tremors might be caused by gaps that were left unattended when the mine shut down. “During mining there are gaps that open between the underground rocks, however these gaps were normally filled with sand mixed with cement to avoid the rock fall. Since there were never preparations for the shutdown, these gaps were left unattended resulting in the falling of big rocks that shake the earth,” Modise said.
While the government dispatched a team of Expert to Selibe-Phikwe to investigate the tremors, Member of Parliament for Selibe-phikwe west Dithapelo Keorapetse has dismissed the exercise, raising doubts about their expertise and experience.
“Minister responsible for mines Eric Molale has confirmed dispatching a team from department of mines to Selibe-phikwe. I am also informed that the team has been asking people in the town some questions regarding the tremors. This is laughable because this is not a sociological, economic demographic survey or study or something like that. It is a complex scientific study that should involve geotechnical engineers or rock mechanics. There is no how Geotech Engineers or rock Mechanics at department of mines can do a proper investigation. Going around interviewing people presupposes that the authorities are clueless and incompetent and cannot help in providing answers to what is happening,” Keorapetse lashed out.
While the Minister of Minerals Green Technology and Energy Security Eric Molale could not be reached for comment, the liquidator Nigel Dixon Warren stated that he could not comment much on what could be the actual cause of the tremors until the facts are known.
“I am not in the business of speculation, so I will not comment on what could be the actual cause of these tremors. What I can tell you is that we have the Botswana Geoscience Institute working with us, they will be installing some equipment to monitor and trace the source of the tremors. Also as BCL, we are independently arranging for some expertise and equipment to be procured and installed. It worth noting that all underground mines, especially in areas that have long been mined out and abandoned, can experience rock falls as the earth’s crust is continually moving around,” Warren stated in his response, stressing that it is normal and generally presents no threats.
Warren stated that most of the underground areas of BCL have been mined out and left behind, therefore it is possible that some of this activity could be taking place. “Such activity will take place when mines are in production as well as when they are on care and maintenance or even closed. It is also normal when you allow portions of the old mining areas to accumulate water because this water re-lubricates the rock and in between fissures, and can cause some movements. Such movements generally represent no threat and are no greater than when mining activities were taking place,” added the Liquidator.