Research Highlights Severe Pollution From Mining

SCIENTISTS are calling for stricter enforcement of regulations compelling mining companies across Africa to clean up the poisonous mess they create while mining to safeguard public health.

Their recommendations follow research conducted over time in different parts of the continent including Namibia, where severe contamination to the environment from heavy metals in some mining settlements has been detected.

Research conducted since 2004 at three mines: Berg Aukus, Kombat and Tsumeb in Namibia shows that soil and some crops that were being grown near these mines had higher levels of metal elements that include copper, zinc, lead, mercury and arsenic than those stipulated by the World Health Organisation (WHO).

The scientists who conducted this study are from the University of Namibia (Unam) and the Czech Republic in Central Europe. They have published some of their findings in reputable journals that include the African Journal of Range and Forage Science and the Journal of African Earth Sciences.

More findings are set to be published soon in the Journal of Geochemical Exploration.

Professor Benjamin Mapani, who teaches geology at Unam and is one of the researchers, says in some of the areas studied, the level of contamination to the environment was ‘worrying’.

“At Berg Aukus Mine the major finding was that the soil and some crops grown near the mine had levels of heavy metal contamination exceeding the WHO guidelines by almost two times especially in the case of arsenic. Lead exceeds the guidelines by almost 40%,” he said.

Over the years, the WHO has developed guidelines regarding acceptable levels of soil contamination by heavy metals from mining. The guidelines relate to places where people farm or live and where livestock graze.

Some of the mines studied in Namibia were set up in the 1970s when monitoring mining effects on the environment was not a priority. The Berg Aukus Mine closed down in 1979, and when findings of this study were shared with the government, it relocated an agricultural college that was based there to Reitfontein in Grootfontein.

The study showed that heavy metals had contaminated crops including carrots, spinach, cabbage and tomatoes. Some crops such as maize do not accumulate heavy metals. Instead, the contamination is confined to the stalks which can be burnt so that livestock do not feed on them. Rosh Pinah Mine in //Karas Region that was also studied is still operational.

Although mining has stopped at Tsumeb Mine, the smelter is still operating. It gets ore from several countries that include the Democratic Republic of Congo (DRC), Zambia and Chile. Kombat Mine, which was also studied, has closed down.

The research found that although contamination was not very serious at Kombat Mine, Rosh Pinah Mine was experiencing a serious problem of dust, which the scientists say may have an effect on the health of people living close to the tailings.

Well-placed sources said after research findings were communicated to the mine management, they started watering the dust to minimise air pollution.

Mapani says, in the case of Rosh Pinah Mine, remedial steps are easier to implement because the mine is still operating.

“At Kombat and Berg Aukus things are very difficult because the mines have ceased operating. Who is going to do what? Rehabilitation of mines is also a costly undertaking.”

At Tsumeb authorities have installed filters and new technology to reduce the amount of fumes coming out of the stocks in keeping with international standards regulating the emission of fumes. The research shows that lead contamination was most prevalent at Berg Aukus and Tsumeb, which have a combined population of approximately 25 000 people.

At Berg Aukus and Tsumeb the main problem was arsenic contamination. To solve this, the report recommends covering the affected areas with uncontaminated soil so that when children play they do not inhale contaminated dust. The other option is to relocate people from affected areas, and the growing of certain grasses that absorb the metals. The grass can then be burnt. This was done successfully in Zimbabwe at Madziwa Mine in the late 1990s.

Prof Percy Chimwamurombe, a Unam microbiologist who was part of this study, says contamination of the environment is a very big problem in African countries. He said in areas where rainfall high, the problem is compounded by the fact that the tailings go into the soil and are moved long distances through erosion. This problem is especially big in South Africa and in Zambia.

According to Chimwamumbe there are new scientific innovations that deal with contamination from mining. In some countries water hyacinth has been planted to absorb some of the heavy metals, sometimes to a point at which the metal in the plant becomes an ore body.

“The weed is then harvested, dried, burnt and the metal recovered,” he says.

In southern Africa, some scientists are revisiting the tailings to see if more metals can be recovered through further extraction.

Mapani, who is the chairperson of the Commission on Geoscience for Environmental Management (GEM) as well as secretary general of the Geological Society of Africa, says a project involving Namibia, South Africa, Zambia, Kenya, Nigeria, the DRC and Cameroon has been developed to deal with contamination from mining. Under the project, which has been running for the past four years, scientists share data and exchange notes on how to tackle the problem.

He says conducting this research has been difficult but necessary. While some mines have been cooperative, others have been very hostile, thwarting free access to some mining sites and frustrating researchers in the process. It has been relatively easy to work in Namibia, South Africa and Zambia.

On the significance of this study, Mapani says any research should be measured against its output.

“The government of Namibia was very responsive to our research results, because we worked with the environmental division of the Geological Survey of Namibia. When we showed them the results they took action.”

There are a lot of abandoned mines in southern Africa but few studies to determine the extent to which they have messed up the environment.

In some countries governments have included an after closure statement when mines are licensed to compel the mining companies to clean up the environment once the mines close. Others have gone further to require mining companies to put substantial amounts of money into a fund as surety in case they abscond.

Mapani says while there is no shortage of legislation to protect the environment and people from the effects of mining in general, implementation remains a challenge in some countries.

While this state of affairs persists, “the poor man feels the pain,” in the words of the late South African Reggae musician, Lucky Dube. This seems to be true in Africa, where research shows that the low income groups are invariably found in the contaminated areas.

Other scientists from Unam who conducted this study are Professor Isaac Mapaure and Professor Fred Kamona.

*Moses Magadza is journalist and editor whose articles have appeared in more than 25 publications all over the world. He is studying further in the University of Namibia School of Postgraduate Studies. Contact: