ZAC CLEAN-UP the coal slurry clean-up has been completed successfully to the satisfaction of the DMRE
Local anthracite producer Zululand Anthracite Colliery (ZAC) reports that the coal slurry clean-up has been completed successfully to the satisfaction of the Department of Mineral Resources and Energy (DMRE).
The cleanup was undertaken largely through the use of manual labour, with excavators removing the spilt material from the area affected and returning it to the mine’s discard dump.
The cleanup occurred following an incident that took place on December 24 last year, which resulted in 1 500 m3 of coal slurry spilling after the end wall at slurry pond 3 failed.
ZAC, which is located in Emakhalathini, KwaZulu-Natal, has also developed a R55-million short-, medium- and long-term Plan of Action as part of the Rehabilitation Plan, which was submitted to the relevant authorities for approval. The action plan will also assist in preventing such failures from occurring in the future.
“Considering all available water quality data from the monitoring programmes that were instituted to quantify and qualify the impacts on the receiving water resources, it was evident that the mitigatory measures implemented by ZAC immediately after the spill contributed significantly towards the containment of a large percentage of the spilt slurry,” states ZAC environmental superintendent Msawenkosi Buthelezi.
He notes that an aquatic ecology assessment conducted by environmental consultant M2 Environmental Connections demonstrated two insights.
The first is that there was no environmental degradation in the Black Umfolozi river. The river remained at present ecological status of Class C, which is in line with the reserve determination of the Department of Water and Sanitation.
The second is that the impact on the water quality in the Black Umfolozi was low.
Moreover, engineering company GFK Consulting Engineers inspected all the existing dams.
“All existing protocols and contingency plans were strengthened in relation to all mine dams,” adds Buthelezi.
Further, ZAC has constructed a berm downstream of the dams in order to contain any possible spills.
Filter Press Update
ZAC is currently installing a 25 t/h filter press at its coal washing plant as another mechanism to prevent future incidents from occurring. ZAC engineering production superintendent Howard Atkinson explains that the filter press will filter slurry-laden water and remove all the ultrafines from thewaterto enable reclaimed water to be reused in the beneficiation process.
The filter press plates and cloths have not been delivered to the site and are currently in the process of being offloaded at the port.
The logistical issues at the port caused by the recent flooding in KwaZulu-Natal have set the project back by two weeks.
“The roof of the filter press will be closed once the plates and cloths have been installed. There have been delays with the commissioning of the plant owing to the delay in the delivery of some parts of the filter press,” he states.
Atkinson conservatively estimates that the filter press plant will be ready for full production by May 16, 2022.
Water Management Strategy
Buthelezi adds that ZAC’s mine water management strategy is pinned upon the principle of clean and dirty water separation as guided by government regulations. Further, the mine consistently monitors water systems throughout the mine area as part of its water-use licence.
“ZAC further works on zero discharge of wastewater to the environment. All our wastewater is contained and reused for coal processing as well as dust suppression activities,” Buthelezi concludes.