NKOMATI ANTHRACITE (PTY) LIMITED - Sentula Mining

Environmental Impact Assessment Report: Nkomati Anthracite (Pty) Limited, Madadeni Opencast
Mining Project Page 71
6.4 R E S I D U A L IM P A C T S PO S T M I N I N G
Residual impacts post mining, in context of this document, is taken as all potential impacts, which may
arise as a result of the mining activities on the proposed Madadeni Opencast mining area following
the decommissioning phase. Note that no partial closure will be applied for.
6.4.1 G e o l o g y
During the life of the mine, approximately 1.4 x 10 6 tons of coal will be removed from the proposed
Madadeni mining project area. The geological profile (target coal seam and overlying strata) on the
proposed Madadeni mining project area, covering an area of approximately 54ha, will have been
permanently disturbed by opencast mining. Note, however, that a core function of any mine is to
remove geological material. No surface subsidence is expected after mining.
The residual impact of mining on geology will therefore be the disruption of the geological profile. No
mitigation measures are predicted for the impacts on geology.
6.4.2 T o p o g r a p h y
During closure, all surface activities that would have impacted on the topography i.e. pollution control
dam, R.O.M coal stockpile area and all other mine infrastructure would have been removed. In view
of this, the surface area will be free draining and approximate the pre-mining surface, hence no
residual impacts are expected.
6.4.3 S o i l s
All soils from the subsoil and topsoil stockpiles would have been utilized during the decommissioning
phase. The area will then be seeded with the recommended seed mix identified to prevent soil loss
and erosion. Since the topsoil stockpile height will not exceed the height of 4m, no significant loss of
soil chemical properties is expected. However, if it is found that the fertility of the soil has been
reduced to critical levels the soils will be fertilised before use, during rehabilitation.
During the rehabilitation, topsoil layer will be spread over the rehabilitated areas and seeded. As far
as possible rehabilitation of the area will be conducted such that the soil distribution and depths
approximate that of the pre-mining environment. No significant residual impacts on soil will therefore
occur.
6.4.4 L a n d U s e an d C a p a b i l i t y
It is however not possible to immediately restore the land capability of the rehabilitated area to premining
land use, hence the after mining land capability of the mined out area will remain grazing.
Until the biological activity of the soils has been restored and its stability is ensured the soils cannot
be considered arable. This activity will take approximately three to four years of management and
maintenance. In view of the above, the after mining land use will be grazing until such time that the
soils in the area is suitable for use as arable land.
No significant residual impacts on land capability will therefore occur.
6.4.5 Na t u r a l V e g e t at i o n
Seeding of all rehabilitated areas during the decommissioning phase will ensure that a sustainable
vegetation cover will establish in the mining area within 2 – 4 years. A vegetation cover suitable for
grazing land use will be established.
No significant residual impacts on vegetation will therefore occur.
NKOMATI ANTHRACITE (PTY) LIMITED COMPILED BY GEOVICON ENVIRONMENTAL (PTY) LTD