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Text Servaas van den Bosch
Namdeb Diamond Corporation (Pty) Ltd (Namdeb) is a diamond-mining company operating in the south-western corner of Namibia in the Sperrgebiet National Park, an area well known for its endemic diversity of floral species.
By its very nature, extracting a non-renewable resource means that mining will not go on forever. To ensure that no major environmental and social liabilities are created during the operation of a mine and that the land will be suitable for other land use when mining has ceased, planning for closure is essential from the outset.
Namdeb’s environmental rehabilitation plan covers the components of infrastructure demolition, pollution clean up, and landscape and biodiversity restoration. Detailed management actions for the different components adapted to site-specific conditions ensure that redundant infrastructure is demolished safely and in accordance with accepted waste-management procedures. These are that polluted soil and water are treated adequately; man-made landforms are stabilised and made visually acceptable; and vegetation is restored in areas of biodiversity importance.
Nearly 100 years of mining alluvial diamonds has created a large mining footprint, part of which will be restored to pre-mining conditions. Areas that have recovered naturally will not be disturbed again.
A number of rehabilitation projects have been deployed since 2007 to actively restore different types of mining impacts on the environment, as set out below.
Variety of re-vegetation trials
A variety of re-vegetation trials were conducted to restore disturbances; to understand the ecology and behaviour of transplanting endemic succulents better; and to ensure that the rehabilitation methods are appropriate, practical and cost-effective. The mining operations affected different species, so pilot studies were conducted in all of the areas, depending on the rehabilitation requirements as stipulated in the rehabilitation plan. Annual monitoring of these trials is conducted to assess the survival rates of the species, usually during the flowering season, just after the winter rains.
Partnering with Government and private institutions has enabled Namdeb to go beyond satisfying legal requirements. The Millennium Seed Bank Project, under the umbrella of Namibia’s Ministry of Agriculture, Water and Forestry and Royal Kew Botanic Gardens in London, assists with developing restoration techniques. Rehabilitation planning is co-ordinated with the plans of the Ministry of Environment and Tourism for the future national park, and ministry staff members are directly involved in Namdeb’s rehabilitation projects.
The Pocket Beaches Site 2 rehabilitation operation was contained in Namdeb’s Mining Area 1 Licence. Initially, an Environmental Impact Assessment (EIA) was done prior to mining. Some of the commitments in this EIA included rehabilitation of the area with no visible signs of mining after five years. The mining operations ceased in 2006/7 and rehabilitation was undertaken successfully.
Restoration of original vegetation
The -5 Metre Beach mining area is part of the Pocket Beaches Site 11 &12 situated in Namdeb’s Bogenfels Licence area. This eight-hectare plot was mined in 2008 and rehabilitated progressively. This involved the process of vegetation removal; vegetation storage; stripping for mining; loading and hauling of the mined-out product; back-filling of the mined-out voids; landscaping; and replanting the removed vegetation. Annual monitoring is conducted to assess the survival rates of the transplanted succulents.
Mining Area 1 is a Namdeb licence area on Namibia’s south-western coast (on the Atlantic Ocean). It is an opencast mine. The mining activity commences approximately eight kilometres north-west of the town Oranjemund and extends northwards for approximately 260 kilometres along the shoreline towards the town of Lüderitz. Due to strict security measures in this area, no scrap was allowed to leave the mine over the past 60 years. This resulted in the accumulation of scrap in a number of scrapyards throughout the mining area.
It is therefore essential that all scrapyards are rehabilitated and the scrap disposed of adequately, and that the disturbed areas are profiled to simulate the natural environment.
In 2008, Namdeb entered into a joint agreement with South Africa Metal Namibia (SAMN) to initiate the rehabilitation of these scrapyards. Scrap is compacted and bailed on site and then transported to Cape Town for further recycling. To date, about 95 000 tonnes of scrap have been removed from these yards.
Namdeb’s rehabilitation plan requires that all pollution be cleaned up before the area is returned to the future landowner in a condition that supports future sustainable land uses.
This article appeared in the Sept’11 edition of FLAMINGO Magazine.