Namibia has about 250 abandoned mines that were not rehabilitated, according to a study.
Dr. Andreas T. Salom and Sonja Kivinen conducted the study, which was published in the South African Geographical Journal.
The study is titled Closed and Abandoned Mines in Namibia: A Critical Review of Environmental Impacts and Constraints to Rehabilitation.
According to the researchers, although the inventory of closed and abandoned mines carried out by the German Federal Institute for Geosciences and the Geological Survey of Namibia put the figure at 157, there could be more than 250 mines.
“This number includes only known sites, as, in reality, more than 250 abandoned mines have never been rehabilitated,” the study says.
The study adds that numerous abandoned and closed mining sites are probably not included in the inventory because of difficulties tracing the sites, scarce information, and a lack of funding.
One of the findings is that Namibia has no solid legislation primarily dealing with mine closure and rehabilitation.
However, the study says other relevant legislatures recognise mining rehabilitation in other applicable legislation relating to or incidental to mines.
It says the unresolved legacy of abandoned mines and the fragmented and incomprehensive legal framework have failed to protect the environment from the adverse impacts of mining.
Namibia has only one research institution, the Namib Ecological Restoration and Monitoring Unit (NERMU), focusing on rehabilitating semi-arid areas.
As rehabilitation efforts need to be site-specific, selecting an appropriate method requires a sufficient understanding of the functioning of the particular ecosystem.
Long-term monitoring should also be conducted to assess whether the rehabilitation of mines has been successful.
The other reason is a lack of skills and dedicated project teams, significantly contributing to unsuccessful mine closures.
In Namibia, the capacity to implement an effective rehabilitation program lacks human capacity within the mining industry, government, and theoretical and applied sciences.
The study also cites the scarcity of scientific literature on the environmental impacts of mining, abandoned mines, and mine rehabilitation in Namibia, reflecting the lack of education and research.
The third reason is the lack of cooperation between the government, the scientific community, and industry sectors.
According to the study, this has been a crucial constraint to successfully planning and implementing mine closure and rehabilitation.
There is also no clear definition of rehabilitation criteria or standards for setting measurable goals for rehabilitation projects.
Furthermore, issues of trust and transparency are also constraints on mine rehabilitation.
Like in many countries, a significant issue of by whom and how rehabilitation should be funded is not yet clearly defined in Namibia.
Rehabilitation projects are invariably expensive, and the costs are also naturally dependent on the rehabilitation criteria and goals.
In abandoned mines, inadequate knowledge of the number and state of abandoned mines complicates accurately estimating the costs.
The Best Practice Guide produced in collaboration with the chamber of mines, the Namibian Chamber of Environment, the government, and members of the Namibian mining industry dealing with issues during all phases of the mining life cycle is an important step forward in addressing questions related to the post-mining phase and abandoned mines.
The Best Practice Guide states that to mobilise resources for the restoration and rehabilitation of impacted sites and abandoned mines, a rehabilitation fund should be set up in the Environmental Investment Fund that will require mining license holders to fund bonds to ensure that they comply with the environmental and rehabilitation obligations.
Health hazards from abandoned mines
The study says the community near the Klein Aub mine, which was operational from 1964 to 2018, is affected by wind-transported dust from the tailings dump.
Similarly, the fine-grained tailings of the Oamites copper-silver mine operational in the 1970s and 1980s contain copper, uranium, lead, and zinc that are eroded and transported by wind.
This causes health risks at the army base in the closed mining site.
Erosion and acid mine drainage from the old pyrite-rich tailings and waste rock dumps of the Matchless mine have caused heavy metal contamination of water and sediments of the Matchless River.
Furthermore, a primary environmental concern related to the Khan mine, operational in 1916–1918 and 1965–1974, is exceptionally high concentrations of copper and nickel in the sediments of the Gruben River Valley.
In the Onguati mining site, closed in 1971, tailings are eroded, and materials are transported to the nearby river, indicated by several times higher concentrations of copper and tungsten than the background values.
The researchers concluded that a more holistic approach is needed to address complex challenges related to abandoned mines and mine rehabilitation in Namibia.
They suggested improving and speeding up the integration of mining and environmental legislation.
They also urged for the establishment of a mine rehabilitation agency under the Ministry of Environment and Tourism that could develop and conduct the environmental remediation and monitoring of abandoned mining sites.
Additionally, they encourage recruiting and training more people to fill up the needed skills for my rehabilitation.
They believe that developing monitoring and assessment of the long-term environmental impacts of mining would help.
According to the researchers, there must be a collaboration with foreign experts with extensive knowledge of mine site rehabilitation.
The researchers point out that Namibia must finalise and implement a binding financing mechanism for mine rehabilitation.
“Although our study focused on Namibia, the lessons learned from the challenges and constraints of mine rehabilitation are likely to apply to many other traditional mining countries with a legacy of abandoned mines,” they said.
