Context: The Directorate of Enforcement (ED) has roped in the Indian Space Research Organisation (ISRO) and the Indian Institute of Technology- Kanpur (IIT-K) to assist investigation into allegations of excessive sand mining in Tamil Nadu.

What is Sand Mining? 

• Sand mining is the extraction of sand through an open pit but sometimes mined from inland dunes from oceans, riverbeds and beaches.

• Sand is the planet’s most mined material, with some 50 billion tons extracted from lakes, riverbeds, coastlines and deltas each year, according to the United Nations Environment Programme.

• Sand is used for manufacturing, for example construction purposes and as an abrasive .

• Desert sand is useless for construction. The wind-weathered grains are too small and smooth for binding in concrete. Sea sand has similar properties from being tossed by ocean currents. 

• The sand that’s ideally sized, shaped and cut out for construction comes from shorelines and the beds of rivers and lakes.

How does sand mining impact the ecosystem?

• Excessive sand mining can alter the river bed, force the river to change course, erode banks and lead to flooding. 

• Disturbance of underwater and coastal sand causes turbidity in the water, which is harmful for organisms such as corals that need sunlight. 

• It also destroys fisheries, causing problems for people who rely on fishing for their livelihoods.

• Mining from streams or rivers upstream can reduce water quality for downstream users and poison aquatic life.

• Sand acts like a sponge, which helps in recharging the water table; its progressive depletion in the river is accompanied by sinking water tables in the nearby areas, adversely impacting people’s daily lives.

Possible Solutions

• Guidelines on the extraction of sand say that the amount of sand removed should be in proportion to its replenishment rate and river width. 

• Mining from a braided channel with a wide floodplain will have less impact than from a narrow channel. 

• Manual mining is preferred over the use of machines but enforcement and monitoring of these guidelines remain weak. 

• Crushing rock produces sand or “crusher dust” provides a potential alternative to river sand.

Conclusion

• Although Sand is required for the development of Human being, at the same time the threats posed due to sand mining can’t be ignored. Hence decisive steps are to be taken & alternate solution to be found for sand mining, without disturbing the environment.