Silica Mining: Related Challenges and Solutions

Reference:

The National Green Tribunal (NGT) while hearing a petition on illegal silica sand mining in Uttar Pradesh has directed the Central Pollution Control Board (CPCB) to prepare detailed all India guidelines for silica sand mining and silica washing plants within three months. These guidelines have been given in the context of irregularities found in the areas related to silica mining.

About Silica:

• It is a major component of silicon dioxide. Its chemical formula is SiO2. It is commonly available in nature in the form of quartz which is obtained from mining.
• Silica sand washing plant is used to remove impurities and contaminants from silica.

Applications of Silica:

• Construction and Mining: About 95% of the commercial use of silica is in the construction industry and mining sector. It is used in the manufacture of tiles, grout, cementing (adhesives), glass industry and Portland Cement Concrete etc.
  • Apart from this, it is also used in drilling and sand blasting.
  • Silica is also used as a raw material for porcelain and other ceramic products.
• In food items: It is mainly used as an anti-foaming and anti-caking agent in spices and powders and food items like non-dairy coffee creamer.
  • It is also used to clean beverages and control stickiness.
  • Apart from this, it is also used as a food preservative. It acts as an inhibitor against the growth of fungus in food items and keeps it fresh.
• In cosmetics: Silica is used in various cosmetics. It is used in making face wash, skin care products, talcum powder, toothpaste etc.
  • Apart from this, silica can also help in the formation of a protein called collagen, which is important in increasing healthy skin and skin elasticity.
    • Skin elasticity is also called skin turgor. It is the ability of the skin to return to its original shape. It is an important factor in healthy and young looking skin.
• In metallurgical industry: Silica has a high melting point, due to which it is used extensively in ferrous and non-ferrous casting industries. Due to its high melting point, casting can be done using molds made from silica sand.
  • It can also be used to absorb excess moisture from metals and prevent them from rusting.
• Biomedicine: Silica-based materials can be used to design bioactive materials in devices and prosthetic applications for drug delivery systems.
• Healthcare: Silica may be useful in the treatment of hypertension, heart disease and arteriosclerosis. It may also help prevent memory loss and lack of concentration.
  • It is also used in the extraction of DNA and RNA as it has the ability to bind to nucleic acids in the presence of chaotropes.
• Telecommunications and Semiconductors: Silica is used to manufacture optical fibers for telecommunications and is widely used in semiconductor technology. 

Effects of Silica Mining:

• Environmental impacts: Clearing of vegetation and soil erosion during silica mining activities can result in habitat loss, loss of biodiversity and widespread disruption of ecosystems. In addition, clearing of vegetation can also increase runoff and soil erosion.
  • Mining and deposit of waste material in quarries can alter the topography and hydrology of the area, affecting natural drainage patterns and water availability.
• Air pollution and respiratory health risks: The formation of fine silica particles from silica mining is a major concern. This is known as Respiratory Crystalline Silica (RCS).
  • Long-term exposure to RCS can cause serious respiratory diseases such as silicosis, lung cancer and chronic obstructive pulmonary disease (COPD).
• Water resource pollution: Silica mining activities can lead to contamination of water resources. The extraction process often requires large amounts of water for washing and processing the silica ore. This can lead to improper handling and discharge of wastewater containing chemicals and suspended solids, polluting surface and groundwater sources.
  • This contamination can harm aquatic ecosystems, water quality and the availability of clean water for nearby communities.
• Socio-economic implications: Silica mining can have socio-economic consequences for nearby communities. It can lead to displacement of local communities and negatively affect their traditional livelihoods, such as agriculture and fishing.
  • Additionally, mining activities can cause social disruptions, including increased migration, changes in community dynamics, and conflicts over access to resources and land rights.

Related suggestions:

• Regulatory measures: Regulatory measures and responsible behavior are necessary to reduce the impacts of silica mining. In this context, the implementation of stringent environmental regulations will ensure proper management of waste materials, including safe disposal of wastes and prevention of water pollution.
• Dust control measures: To prevent pollution from RCS, adequate ventilation systems and personal protective equipment should be provided to protect the health of workers. Apart from this, the following measures can be included for dust control-
  • Wetting or Covering Operations
  • Water Sprays and Misting Systems
  • Dry Fog Technology
  • Ventilation and Exhaust Systems
  • Dust Collectors, such as Baghouse Systems and Cyclone Collectors
  • Pneumatic Conveyance Systems
  • Wet Electrostatic Precipitators
• Community Participation and Sustainable Mining Practices: For sustainable silica mining, it is important to engage with local communities and include their views in decision making.
  • In this context, community development programs such as education and skill training can address the socio-economic problems of the affected communities.
  • Encouraging the adoption of sustainable mining practices, including land reclamation and biodiversity restoration, can help reduce the long-term environmental impacts of silica mining.