Environmental management in chrome mining along the Great Dyke : a case study of Zimasco Operations

[摘要] ENGLISH ABSTRACT: In an area where mining activities dominate, there are likely to problems that need effective environmental management approaches, which can be facilitated through legislation and environmental management systems (EMS). The Great Dyke in Zimbabwe is a strategic economic resource with significant quantities of chrome and platinum. Chrome mining occurs across the whole length of the Great Dyke with most of the operations under Zimasco claims. Zimasco mining operations fall into two categories: the organization‟s own claims operated in its own right and claims that are leased out to a second party forming a tribute system from which tributor miners produce chromite ore exclusively for Zimasco.This study examines the environmental management approaches used by Zimasco operations, in particular the National Occupational Safety Association (NOSA) Integrated Five Start System, in order to identify the usefulness of EMS in the mining industry. Firstly, the current environmental impacts associated with the mining activities were identified and problem areas highlighted, after which environmental management approaches linked to national legislation were examined in terms of their contribution towards sound environmental management. A legal compliance checklist was carried out on the existing mines to assess levels of compliance to standards stipulated in the Environmental Management Act Chapter 20:27. This was followed by questionnaire surveys used for impact identification and the data was analysed using the aspect and impact analysis matrix. Underground mines with effluent discharges were assessed by means of an effluent analysis as a way of determining the effectiveness of the approaches on the mines. Recommendations for changes were made following a Strength Weaknesses Opportunities and Threats (SWOT) analysis of the approaches and system. Major environmental problems highlighted included unattended waste rock dump and pits as well as dissolved substances in effluent discharge. Although evidence of compliance to environmental legislation for the mining operations was found at administrative level, this was often not executed in operation. Limited hazards were observed in effluent discharge from mines under full implementation of the EMS.It is recommended that all mining operations need to be covered by an EMS system for improved environmental management and sustainable development. Effective implementation of legislation and EMS on the ground provides a better platform for sound environmental management.

[发布机构] Stellenbosch University