Minimising mining impacts on flora and fauna and site rehabilitation

South Africa Mining Sustainability_IMG

It has been well documented that underground and open-cast mining activities have an impact on local biodiversity throughout the mining life cycle, from exploration to closure. 

A major, negative impact that a mine will have on the surrounding environment is due to the airborne dust emissions generated by its activities.  Activities such as bulldozing, excavating, blasting, and hauling of ore on unsealed roads all contribute to these major dust generating actions.

Silica and coal dust particles are of a particular concern as they are generally small enough to be easily raised and carried away by wind. This mineralic dust often contains lead or selenium, which are hazardous not only to humans, but flora and fauna as well. 

Erosion and de-stabilisation of soil is another concern that mines need to contend with as they rehabilitate and revegetate large areas of land post mining activity. 

Mining operators have a social and legal responsibility to implement solutions which minimise the impacts of mining activities on natural flora and fauna. In this blog post, Dust-A-Side is focusing attention on dust and erosion control measures that mines can implement to help achieve sustainability and eco-friendly operating targets. 

Preventing airborne dust from haul roads with dust control products 

The exposure of wildlife to trace toxic elements found in airborne dust can be severe, whether dust is visible or respirable (less than 10 microns in size). When exposed to dust, animals can suffer from a variety of health disorders such as severe heart and respiratory problems. 

Additionally, surface water contamination from dust decreases aquatic oxygen content and light penetration, reducing the growth of aquatic plants and resulting in the direct mortality of aquatic species. 

Since haul roads are the biggest contributors to airborne dust in mine sites, it is imperative that mining operations adopt effective strategies to combat this.

Dust control products are at the forefront of preventing airborne wheel generated dust impacting the environment. The goal of dust suppression is to prevent dust from reaching places it can cause harm, rather than undoing the damage, fit for purpose dust palliatives are available in the market today for mines to choose from. Common families of the dust palliatives binders include bitumen emulsions, lignosulfonates, and polymers. 

Each chemistry works in different ways to capture and reduce dust. For example, some dust palliatives are formulated to act as a hygroscopic (moisture attracting) and crusting agent that bind surface particles together on the roads. The crusting effect results in the containment of fugitive dust every time a dump truck rides over the treated road surface. When used in the right concentration and for the right application, many dust control technologies are highly effective at preventing tyre generated dust from becoming airborne. 

Such solutions can be easily applied to haul roads using water bowsers via a series of light dilutions, at recommended reapplication frequencies depending on the technology used, nature and volume of road used and climatic conditions. For longer lasting results at significantly reduced ongoing effort, a binder such as bitumen-based emulsion can be incorporated into the wearing course layer of a haul road during the initial establishment phase. This approach is done to effectively bind materials together and provide a surface seal that significantly reduces wheel-generated dust and the ingress of water into the road-base. 

All dust suppression products produced and supplied by reputable vendors, such as Dust-A-Side, are based on concentrated, environmentally friendly, dust palliatives with exceptional binding properties. They pose no risk nor harm to surrounding vegetation or wildlife when managed correctly. 

Ultimately, the correct use of dust palliatives on haul roads results in significant reductions in wheel generated dust emissions, which is a major benefit to the welfare of local flora and fauna. 

Achieving erosion control and soil stabilisation for rehabilitation

In addition to dust impacts on flora and fauna, erosion and soil stabilisation is another environmental concern mines need to manage. This is particularly pertinent with open-cut mines.

Open-cast mining involves the complete removal of vegetation and topsoil layer, removing habitat that sustains ecological communities. This can also cause soil erosion and degradation of adjacent land, as well as sedimentation and contamination of nearby water bodies.

When an open-cast operation moves into a stage of site rehabilitation, it is critical that soil stabilisation and erosion control is considered. Soil stabilisation and erosion control is necessary to prevent fine soil runoff in wet conditions or becoming airborne in windy conditions particularly, while new vegetation is being established.

To reduce soil erosion or stabilise embankments, mines can use spray-on soil stabilisation products such as AquaTarp. This product is a solvent-free, water and surfactant-based emulsion of latex polymer and is specifically designed and formulated for easy application onto large, exposed areas.

When spraying onto areas where revegetation is to take place, DAS Product is an ideal solution that penetrates the top layer of the soil and forms a light but protective layer that bonds to the underlying surface.  In the right application rates DAS Product can also be mixed with seeds to promote germination.  This helps promote more rapid revegetation while protecting against soil erosion and maintaining dust control. 

Correct application of these products will help achieve re-growth of flora so that habitats and areas are revitalised back to the way they were prior to mining. 

Looking for environmentally friendly dust control solutions? Talk to Dust-A-Side 

We take our commitment to sustainability seriously, and as a result we have developed many products which are safe to both humans and nature.

To learn more about our cutting-edge dust control solutions, call us on +27 (0) 12 648 8900. Or you can get in touch by clicking here.