| Summary: | The asbestos mining industry has left a legacy of pollution that continues to poison former mining areas and
surrounding land – posing a significant health risk to local communities. The rehabilitation of sites disturbed
by mining activities, aims to negate the adverse effects associated with these post-mining landscapes and to
achieve the return of a disturbed site to a degree of its former state or to a sustainable usable condition. In
order to assist the effective rehabilitation of derelict and ownerless asbestos mines it was critical to develop a
scientific database to indicate the status of rehabilitation at specific sites. The Rehabilitation Prioritisation
Index (RPI) was developed in 2007 to indicate the sequence for rehabilitation of asbestos pollution by
quantifying the risk associated with a specific pollution site. The use of the RPI has been implemented by the
South African Department of Minerals and Energy as part of an integrated approach towards the
rehabilitation of the asbestos legacies of the past. In this study, a multidisciplinary approach was applied to
sites in three provinces as identified in the RPI, to facilitate the development of the Rehabilitation Monitoring
Index (RMI). It is envisioned that this index, as part of a larger monitoring database, would assist in the
successful monitoring and long-term rehabilitation of asbestos mines. During the monitoring process, the
most prominent aspects governing the rehabilitation process were identified from comprehensive
assessments of quantitative and qualitative data. Quantitative parameters included cover depth, physical and
chemical soil properties, soil microbial activity, vegetation properties and small mammal surveys. Qualitative
data included the footprint area, land use, erosion or flood damage, secondary pollution and water control
structure damage. From the quantitative data, those parameters which had the greatest influence on the
rehabilitation process were identified. In order of most to least important these groups were analysed by
multivariate statistical ordination and classified into four groups: success parameters > essentials to be
addressed > reasons for failure > non-distinguishable entities. The qualitative data indicated that the Limpopo
Province was in the highest state of degradation after rehabilitation and that site history plays an important
role in rehabilitation planning. Quantitative and qualitative parameters were assessed for all sites and applied
in the RMI as weighted factors from which the rehabilitation status of a specific site can be calculated.
Qualitative data was given a weight of 25% and quantitative data a weight of 75%. RMI values were
calculated for each parameter and sites were distributed across a range which classifies the sites according
to their rehabilitation status. Once again the Limpopo Province was identified as the province with the least
successful rehabilitation. The results from this investigation show that a multidisciplinary approach is a step
in the right direction for the successful monitoring of rehabilitated post-mining sites such as asbestos mines.
It is however necessary that the RMI must be validated and the weights allocated to qualitative parameters
must be reconsidered for the future development of this tool. While the RPI and RMI cannot be compared
directly, it might be of great revelation to reassess the RPI values of all the sites after rehabilitation and
compare this data to the RMI values. === Thesis (M.Sc. (Environmental Science))--North-West University, Potchefstroom Campus, 2010.
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