EIA-REP-325d-12 _BB_ - 201.09.14.pdf - SAHRA

• Characterise the topsoil and retain it for use in rehabilitation. It is preferable to reuse the topsoil
immediately rather than storing it in stockpiles. Only discard if it is physically or chemically undesirable, or
if it contains high levels of weed seeds or plant pathogens;
• Consider spreading the cleared vegetation on disturbed areas;
• Deep rip compacted surfaces to encourage infiltration, allow plant root growth and key the topsoil to the
subsoil, unless subsurface conditions dictate otherwise;
• Ensure that at the surface one or two metres of soil is capable of supporting plant growth;
• If topsoil is unsuitable or absent, identify and test alternatives substrates, e.g. overburden that may a
suitable substitute after addition of soil improving substances;
• Re-vegetate the area with plant species consistent with the post mining land use; and
• Monitor and manage rehabilitated areas until the vegetation is self-sustaining.
Rehabilitation guidelines during the decommissioning phase should adhere to the following guidelines:
Site grading
The local environment in un-rehabilitated disturbed mining areas is unfavourable to vegetation establishment.
Lack of topsoil, combined with uneven and often quite steep slopes hinders plant germination and establishment.
While the disturbed slopes are being graded, care must be taken to ensure proper drainage of the site.
Consideration should at this time be given to the creation of berms at the pit entrance, to screen the site and to
prevent further unauthorized access.
Spreading of stored topsoil
Once the disturbed area’s – box cuts as well as the new pit area - backfilling, grading and sloping is complete,
subsoil and topsoil from storage berms located outside the mining area should be spread on the slopes as evenly
as possible. When this has been completed, the next stage in the rehabilitation program should immediately
commence to prevent erosion and topsoil loss.
Decommissioning and closure will entail the following:
• Slope and whaleback the slopes of both the old box cuts as well as the new pits to a gradient of at least
1:6 in order to accommodate any future agricultural activities within the area;
• The topsoil will be stockpiled as detailed in the previous section;
• Topsoil will be spread out over prepared areas to a depth of no less than 300mm, unless otherwise stated
(see the ‘topsoil stockpiling’ section above);
• Neat stockpiling of oversized rock in the one corner of the pit or alternatively clustering rocks on long
slopes with gradients of 1:6 to reduce erosion through water run-off and facilitate plant growth by
providing seedlings and seeding of the disturbed area;
• Remove the concrete/impermeable floor where refuelling occurred;
• Remove all containers;
• Decontaminate any hydrocarbon spills by removing the soil and disposing of it at a licensed disposal
facility;
• Remove the temporary fencing;
EIA-REP-325d-11
October 2012
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