Four environmental risks of explosives and how to mitigate them

Public awareness of mining-related ecological challenges in Africa is growing, and companies are now expected to go the extra mile to ensure that operations such as blasting cause little to no disruption in natural habitats and communities.

However, the use of explosives to break ground and extract rich natural resource deposits can significantly and catastrophically impact soil and water quality, and result in both air and noise pollution. If managed poorly, explosives can leave a lasting mark on the environment and lead to community pushback, backlash from protection groups, and fines from government.

Due to the sheer amount of oversight, preparation, and administration required, not to mention difficulties and expenses related to appointing the right kind of experts, many African mining companies turn to explosives consultants and management providers like Mining and Energy Acuity (MEA) to provide guidance and help set up certain guardrails.

Here are some pointers and insights on managing these types of risks in mining operations.

Environmental risks and how to resolve them:

1.     Soil contamination

Explosive materials constitute a variety of highly volatile chemical compounds and heavy metals that, if they leach into the ground, will alter the pH level of the surrounding earth, and compromise microbial life essential for healthy soil. In areas with sensitive biodiversity or farmland in close proximity to mine boundaries, the risk of chemical infiltration is especially concerning.

Implementing strategic detonation methods and more sustainable explosives formulations can significantly reduce the chemicals that reach the soil. Furthermore, by using precise electronic detonators and optimised blast designs, mining teams can limit overbreak and avoid using excessive amounts of explosives. Over time, this minimises the volume of chemicals released into the surrounding environment.

Additionally, post-blast remediation techniques such as bioremediation can help restore soil health. Select microbes or plants can be introduced to degrade, immobilise, or extract contaminants from the soil. When combined with soil washing or other mechanical methods, these operations prevent dangerous residues from spreading further.

Expert guidance from specialists like MEA, with experience in environmentally-mindful blasting and remediation practices, can help mines integrate these solutions effectively without overwhelming existing site operations.

2.     Water contamination

Surface and underground water resources can also be directly impacted by mining explosives, with residual chemicals filtering into streams, rivers, and groundwater if not strictly controlled. In countries like South Africa, where water scarcity already impacts many communities, even low-level contamination can have an outsized impact.

Forward-thinking water management should begin before a single charge is detonated. Mines can establish retention ponds and controlled drainage systems designed to capture run-off from blasting zones, ensuring that contaminant-laden water is contained and does not seep into broader waterways. This run-off can then be treated using filtration systems, which may include activated carbon or ion exchange resin tailored to the specific contaminants.

3.     Noise pollution

Blasts set off too close to populated areas that generate high decibel levels can disturb or even displace wildlife, and the shock waves can damage surrounding structures if poorly managed. Moreover, high vibrations risk destabilising rock formations or previously installed ground support systems, posing safety risks for mine workers.

Highly controlled blasting sequences and advanced noise suppression methods are valuable in mitigating these challenges. By employing modern electronic detonation systems, blast operations can limit the peak particle velocity (PPV), thereby reducing both the magnitude of vibrations and associated noise. Additionally, physical noise barriers, like strategically placed berms or sound-absorbing structures, can be erected near active faces.

4.     Air pollution

Explosive detonations inevitably cause dust clouds, releasing fine particulate matter into the air. Depending on the composition of the rock and the explosives, these emissions can include potentially hazardous substances. Over time, workers or nearby residents exposed to dust-laden air may face respiratory problems, while the dust can also settle over fields and crops, affecting local agriculture.

Mines can adjust the types and amounts of explosives to limit excessive fracturing and dust creation. Likewise, employing wet drilling or water mist systems, particularly around the perimeter of a blast zone, is a straightforward and relatively inexpensive approach that significantly reduces dust emissions at the point of generation. In some cases, setting up windbreaks around open-pit operations or drilling areas can also help trap particulates before they disperse into adjacent communities.

The role of specialised service providers like MEA is to ultimately enhance efforts to adopt advanced blasting techniques and remediation technologies. Our experts help to limit environmental pollution by providing clear guidance and refined compliance strategies to address site-specific ecological challenges.