Why Rat-Hole Mining in News?
The Silkyara tunnel collapse presented a unique challenge. The trapped workers were located deep within the collapsed tunnel, making it difficult to reach them using conventional rescue methods. Modern machinery, such as auger drilling machines, proved ineffective due to the presence of obstructions and challenging terrain.
In this desperate situation, rat-hole miners, with their expertise in navigating narrow underground spaces, stepped forward. Their ability to maneuver through confined spaces and excavate tunnels quickly proved invaluable. Despite the inherent risks associated with rat-hole mining, these skilled individuals, often stigmatized and marginalized, played a pivotal role in the rescue efforts. They demonstrated the resilience and resourcefulness of the human spirit in the face of adversity.
What is Rat-Hole Mining?
Rat-hole mining is a method of manual coal extraction that involves digging narrow, vertical pits into the ground, typically just wide enough for one person to fit through. These pits, known as “rat holes,” can be up to 100 meters deep and extend horizontally for long distances. Miners descend into these rat holes using ropes and bamboo ladders and extract coal using hand tools.
Rat-hole mining is a dangerous and illegal practice that has devastating consequences for both miners and the environment. The Indian government must take stricter measures to enforce the ban on rat-hole mining and provide alternative livelihoods for those who depend on this hazardous practice.
Why is Rat-Hole Mining Dangerous?
Rat-hole mining is considered extremely hazardous due to a number of factors:
- Lack of safety measures: Rat-hole mines are typically unregulated and lack basic safety measures such as proper ventilation, structural support, and safety gear for workers. This creates a dangerous environment that can lead to suffocation, injuries, and fatalities.
- Structural instability: The narrow, unsupported tunnels are prone to collapses, trapping miners underground.
- Exposure to harmful substances: Miners are exposed to harmful substances such as coal dust and methane gas, which can lead to respiratory problems and other health hazards.
Environmental Impacts of Rat-Hole Mining
Rat-hole mining also has significant environmental impacts:
- Land degradation: The digging of rat holes and the removal of coal can lead to land degradation and soil erosion.
- Deforestation: Rat-hole mining often involves clearing forests to make way for mining operations.
- Water pollution: The runoff from mining sites can pollute nearby water sources with coal dust, heavy metals, and other contaminants.
Ban on Rat-Hole Mining
In 2014, the National Green Tribunal (NGT) of India banned rat-hole mining, citing its hazardous working conditions and environmental impacts. However, the practice continues illegally in some areas of Meghalaya.
In addition to rat-hole mining, two other methods were employed to rescue the trapped workers in the Silkyara tunnel collapse: vertical drilling and auger mining.
Vertical drilling involves using a boring machine to dig a straight shaft directly down from the surface. This method was utilized in the Silkyara tunnel collapse, and an 800-mm pipe was inserted into the drilled shaft to serve as a passage for bringing out the trapped workers.
Auger Mining (Horizontal Drilling)
Auger mining, also known as horizontal drilling, utilizes a specialized machine, the auger machine or directional drill, to create horizontal tunnels without disrupting the surface ground. These machines are commonly used for laying down water and gas pipes and for digging tunnels.
In the Silkyara tunnel collapse, the auger machine was initially employed to create a horizontal tunnel towards the trapped workers. However, this method proved unsuccessful due to encountering metal obstructions, and the auger machine itself ultimately broke down, rendering it unusable.