Coal India output in Northeast drops to 2L tonnes from 7.8L in six years
Constraints include difficult geomining conditions & economic unviability that has led the CIL to suspend operations in many mines
Guwahati, July 8: Coal production in the Northeast by Coal India Limited (CIL) is going down, with the state-owned coal producer suspending mining operations in many mines due to various constraints like difficult geomining conditions, economic unviability, non-availability of suitable mining methods and non-availability of forest and environment clearances, according to a Coal Ministry report.
CIL’s production dropped from 7.84 lakh tonnes in 2018-19 to 2 lakh tonnes in 2024-25, the report stated.
“Exploring and developing coal resources in the North Eastern Region (NER) of India present several significant challenges due to a combination of environmental, topographical, and geological factors. One of the foremost constraints is the extensive forest cover that characterizes much of the region,” the report stated.
“Overall, prognosticated coal bearing areas of NER has a predominantly high level of forest cover, with most areas showing near-complete or complete forestation. There is only about 128 sq km of unblocked area, available in the region where the forest density is expected to be less than the 90 per cent,” the report added.
There are five CIL blocks and 11 non-CIL blocks in the northeastern region at present. All five CIL blocks are explored in detailed, whereas, out of 11 non-CIL blocks, five blocks are explored and exploration is ongoing in remaining six blocks.
Currently, mining activities of CIL are concentrated mainly in the Makum coalfield only. All underground coal mines of the Northeastern Coalfields are closed since November 2008 due to an explosion in the Ledo mine. The only active operation area is Tikak Extension OCP in Tikak colliery.
Moreover, the nature of coal deposits in the region adds another layer of complexity to exploration efforts. The region’s coal seams are known for their variability, including thin seams and the pinch-and-swell nature of the deposits.
Thin seams, which are less than a metre in thickness, pose significant challenges for efficient mining and can lead to lower economic viability compared to thicker seams. The pinch-and-swell nature of coal deposits, where the seam thickness fluctuates irregularly, makes it difficult to accurately estimate the quantity, quality and extension of the coal deposits available.
Additionally, the presence of high sulphur content can reduce the coal’s overall market value. Sulphureous coal requires additional processing, such as desulphurization, to make it more suitable for use in power generation and industrial applications. This added processing not only increases the cost of utilizing the coal but also complicates its integration into existing energy systems.
As a result, while the Northeast holds substantial coal reserves, the high sulphur content of its coal reduces its attractiveness compared to low-sulphur alternatives, necessitating enhanced processing techniques and affecting its economic viability, the report stated.
The prognosticated coal bearing areas of 938 sq km has been identified in the northeastern region. Out of this area, 835 sq km is in tertiary coalfileds and 103 sq km in Gondwana coalfields. Around 654 sq km of prognosticated coal-bearing areas in the region is still unexplored.
As per the Inventory of Coal Resources, Meghalaya tops the list with 583.22 million tonnes followed successively by Assam with 525.01 million tonnes. Majority of ‘Measured Resources’ in the Northeast is found in Assam (464.78 million tonnes).
Coal deposits in the region are primarily tertiary in age (younger and lower ranked) and are found in Assam, Meghalaya, Arunachal Pradesh, Nagaland, Mizoram and Sikkim. These deposits are typically characterized by thin seams with high sulphur content, low ash, and high carbon, contributing to a high calorific value. Gondwana coal is also present in Assam and Sikkim.