Rat Hole Mining in Meghalaya
Context:
The issue of rat-hole mining in Meghalaya has resurfaced following a tragic explosion in an illegal mine, killing at least 18 workers.
This incident highlights the persistence of the practice despite a ban and ongoing court supervision
About Rat Hole Mining & Coal Deposits:
It is a primitive, sub-surface mining method where small tunnels (resembling rat holes) are dug to extract coal.
This method is perilous as the mines often lack engineered roofs and side-wall protections, making them prone to collapse.
Meghalaya has an estimated 576 million tons of coal deposits.
These deposits are spread across various districts in patches of different sizes, often controlled by individual landowners.
The practice is extensively prevalent in the Jaintia Hills and other districts of Meghalaya.
NGT Ruling:
The National Green Tribunal (NGT) ordered a complete cessation of rat-hole mining in 2014.
The ban was imposed due to the unscientific nature of the mining and its severe environmental impact, including:
Large-scale deforestation and degradation of agricultural lands.
Acid mine drainage leads to "scarcity of water" and pollution of air, water, and soil.
the mines are death traps for workers, with frequent accidents and the use of child labour
Charecteristics of Coal in India:
Coal is a combustible black or brownish-black sedimentary rock with a high amount of carbon and hydrocarbons.
Coal contains carbon, volatile matter, moisture, and ash & [in some cases Sulphur and phosphorous].
Classification of Coal:
Classifications are based on the amount of carbon, oxygen, and hydrogen present in the coal.
4 main types: anthracite, bituminous, subbituminous, lignite
Anthracite
best quality of coal and contains 80 to 95 percent carbon and veery little volatile matter
very hard, compact
found only in Jammu and Kashmir (in Kalakot) and that too in small quantities
Bituminous
carbon content: varies between 60 to 80%
High calorific value and low moisture
Most of the bituminous coal is found in Jharkhand, Orissa, West Bengal, Chhattisgarh, and Madhya Pradesh
Lignite
Also known as brown coal, lignite is lower-grade coal and contains about 40 to 55 percent carbon.
Its moisture content is high (over 35 percent)
It is found in Palna of Rajasthan, Neyveli of Tamil Nadu, Lakhimpur of Assam, and Karewa of Jammu and Kashmir.
Tamil Nadu accounts for 90 percent of the reserves and about 71 percent of the production of lignite in India.
Peat
Coal Reserves in India:
With the fifth-largest geological coal reserves globally and as the second-largest consumer, coal continues to be an indispensable energy source, contributing to 55% of the national energy mix.
Distribution of Coal in India:
Gondwana Coal fields that are 250 million years old
makes up to 98% of the total coal reserves in India and 99% of the coal production in India
free from moisture and contains phosphorus and sulphur.
The carbon content is less compared to the Carboniferous coal (350 million years old).
These basins occur in the valleys of certain rivers viz., the Damodar (Jharkhand-West Bengal); the Mahanadi (Chhattisgarh-Odisha); the Son (Madhya Pradesh Jharkhand); the Godavari and the Wardha (Maharashtra-Andhra Pradesh);
Tertiary Coal fields that are 15 to 60 million years old.
Carbon content is very low but is rich in moisture and sulphur
Tertiary coal fields are mainly confined to extra-peninsular regions.
Important areas include Assam, Meghalaya, Nagaland, Arunachal Pradesh, Jammu and Kashmir, Himalayan foothills of Darjeeling in West Bengal, Rajasthan, Uttar Pradesh, and Kerala.
Garo, Khasi, and Jaintia hills are believed to have deposits of tertiary coal belonging to the lower Eocene