Guidelines for Silica Sand Mining and Washing Plants: CPCB’s New Framework

Introduction

The Central Pollution Control Board (CPCB), under the Ministry of Environment, Forest and Climate Change, has issued Guidelines for Silica Sand Mining and Washing Plants following an order of the National Green Tribunal (NGT) dated 29 November 2024. These guidelines aim to regulate mining and washing activities under the Water Act, 1974, the Air Act, 1981, and the Environment (Protection) Act, 1986. By defining clear procedures and management practices, the guidelines seek to control pollution, conserve resources, and ensure sustainable silica sand mining across India.

Background and Legal Framework

The guidelines were prepared in response to the NGT’s direction in Devidas Khatri vs Union of India & Ors.
Silica sand, quartz, and quartzite were declared minor minerals under the Mines and Minerals (Development and Regulation) Act, 1957.
A notification in February 2025 revised the list of minor minerals, impacting regulatory oversight.

Distribution and Industrial Uses of Silica Sand

Silica sand is abundant in states like Uttar Pradesh, Rajasthan, Gujarat, Andhra Pradesh, and Maharashtra. The Prayagraj district in Uttar Pradesh, particularly Shankargarh, is a key hub for high-quality silica deposits.

Industrial applications include:

Glass manufacturing
Foundry sand
Ceramics
Silicon and silicon carbide production
Water filtration
Oil and gas hydraulic fracturing
Electronics and fiber optics
Construction materials and abrasives

Mining Process and Environmental Issues

Mining Practices

Typically carried out by open-cast methods, with manual tools or semi-mechanized machinery.
Coastal mining faces restrictions under the Coastal Regulation Zone (CRZ) notification.

Key Environmental Impacts

Land Degradation: Loss of fertile soil, altered drainage, and reduced vegetation.
Biodiversity Loss: Depletion of green cover, affecting ecosystem balance.
Air Pollution: Dust emissions disturb local flora and pose health hazards.
Water Contamination: Runoff from mining sites pollutes nearby water bodies.

Pollution Control Measures for Mining

Dust suppression using water spraying and anti-smog guns.
Proper fencing and boundary marking to prevent illegal mining.
Afforestation and green belt development (5–7 m wide).
Medical checkups for workers exposed to dust and noise.
Emergency planning and seasonal restrictions (no mining during rains).
Mining restricted to unsaturated zones above the groundwater table.

Crushing and Washing Practices

Crushing

Dust control through covered conveyors, paved roads, and water sprinkling.
Monitoring of PM10 and PM2.5 emissions.
Worker safety via PPE (dust masks, gloves, ear muffs).

Washing

Techniques: Scrubbing, washing, rinsing, and dewatering.
Water usage depends on impurity levels (up to 9 times the raw material).
12–15% water loss during washing; recycling is mandatory.
Units must ensure zero liquid discharge through settling tanks.

Pollution Controls in Washing:

Covered conveyors, sprinklers, and paved roads.
Rainwater harvesting and CGWA-compliant groundwater use.
Dense green belts around plant sites.
Clay and waste sand reuse for embankments, roads, and brick making.

Drying and Final Processing

Washed sand contains ~10% moisture; drying reduces it to 0–4%.
Drying methods: Sun drying or mechanical dryers (using LPG or LDO fuel).
Pollution control: covered sheds, APCDs, proper stack height for fuel emissions.
Residual mud must be reused for pit refilling and land restoration.

Conclusion

The Guidelines for Silica Sand Mining and Washing Plants create a structured approach to ensure environmental protection while meeting industrial demands. By regulating water use, reducing dust, recycling waste, and mandating green practices, CPCB emphasizes sustainability. For operators, strict compliance will not only protect ecosystems but also enhance efficiency and reduce regulatory risks.

Download: Silica Sand Mining Guidelines for Washing Plants