Sunday, October 4, 2015

Mining in India

Mining in India

India is endowed with huge resources of many metallic and non-metallic minerals. Since independence in 1947, there has been a rapid growth in the mineral production both in terms of quantity and value. Currently, India produces as many as 87 minerals, which include 4 fuel, 10 metallic, 47 non-metallic, 3 atomic and 23 minor minerals (including building and other materials).

The mining activities are extremely poorly regulated. As early as 1948, the founding fathers of the constitution realized this need for proper regulation. During the Constitutional debates, they said, “Industrialisation has brought in its wake an ever-increasing demand for mineral resources. These resources are non-replenishable and mostly scarce. Proper control over regulation and development of mines and minerals is therefore, a matter of national concern.[i]” Today over 80,000 mines operate illegally as against nearly 10,000 legitimate leases. Only a third of the legal mines actually report to the Indian Bureau of Mines, the regulator and only a tenth of them is inspected.

The concerns of ecological damage and environmental impacts and the consequent effects on people are therefore receiving less attention than it deserves. The Ministry of Statistics and Plan Implementation (MOSPI) states that, “Mining, unless properly regulated, can have adverse environmental and social consequences. On the one hand, mining disturbs the soil, water and ecological regimes and on the other hand, unless accompanied by proactive measures to promote inclusiveness through social education, health and other interventions, it can lead to alienation of the local population and assume socially unacceptable dimensions. Issues of Technology for zero waste or low waste mining, relief & rehabilitation, mine closure which otherwise leads to land degradation are important issues which require continuous attention[ii].”

Typically mining takes place either by digging through the surface or by digging under the surface and are called open-cast mining and underground mining respectively. While underground mining does not show visible signature of destruction of land, but eventually the area is affected either because of subsidence or the area getting parched for not being able to retain the moisture.  Thus, mining is one of the most destructive of human economic activities. Therefore it is often called a “surgery of mother earth” to remove materials for human use. We will only highlight the biophysical impacts of mining in this module.

Mining and Impact on Land

Mining devours a large area of land. The total area under mining and abandoned after mining is exactly not known. The total land under mining is estimated to be greater than 1.30 million hectares. Land under coal mining and abandoned coal mines alone is around 0.36 million hectares[iii].

The impact of mining on land is not restricted to the mining lease are alone. The amount of land affected depends on the topography, the quality of the mineral and the depth at which the mineral is available.

The amount of material to be removed before reaching the mineral is called the “overburden”. More the overburden more land is required for dumping this material. Coal occurs in layers called “coal-seam” in between other sedimentary rocks such as sandstone and shale. Often several hundred meters of rocks are to be removed before reaching a coal-seam and after mining every seam, again the intervening rocks have to be removed. The proportion of coal to overburden can be as high as 1:5 but in general it is never below 1:2. This means that land is required to store the waste materials which will be twice as much as the coal we mine and upto five times. This requires a large area of land as the dumping of these materials has to be scientific and in low angles that will not allow it to slide and affect adjoin areas. In several cases this is over twice the area involved in mining. If the region of mining has an undulating topography with steep slopes more area will be required for storing the overburden materials.

The quality of the mineral found also impacts the land area required. In we have a poor quality of mineral the amount of material required to be mined will be higher. Again if we look at the example of coal, most Indian coal deposits have 30-40 percent of non-coal material along with it. So when the coal is burnt in a thermal power plant to produce electricity we are left with 30-40 percent of the material used as ash. We once again need more land to dump this ash. Over the life-time of a thermal power plant, ash dumps require more land than the actual plant itself.

The amount of materials mined for securing small quantities of metals is generally not understood by common people. For example to get one tonne of aluminium nearly 6 tonnes of rock has to be mined.

In case of precious metals the ratios are staggering. A gold ring weighing 5 grams would have required mining of nearly 6-8 tonne of rock. In case of diamond it is still higher. It is for this reason that these metals are expensive. Uranium mining for instance requires almost 30 tonnes for a gram. This means that we require large land areas to place these waste materials.

Average Viable Quantity to Mine
Compiled by Environics Trust from various sources, 2014
As we go into the future, many of our shallow deposits would have been used and we would need to dig deeper and also use poorer quality of deposits to meet our needs.

If we look at gold mining over the past we find that in the last century the amount of gold required for mining profitably has dropped significantly and proportionately the amount of overburden and waste generated has increased many times over.

The land area required is one aspect but the quality and type of land being used for mining and dumping of overburden and waste adds another dimension to the impact on land.

Mining alters the topography of the land and along with the manner in which the overburden is dumped completely changes the initial contours. This has impact on the local slopes and alters the drainage pattern in the area. We will look at the impacts it has on water in a later section. If mining takes place in forested areas, agricultural lands and common lands of people the impacts are not limited to just losing the land area.

Mining and Impact on Forests and Agricultural Lands

It is estimated that over 164,000 hectares of forests have already been lost to mining activities. Considering the fact that in future we will be mining in the last of the original forests the impact is going to be larger and far reaching.  

The forests not only completely disappear because of mining, but with the initiation of mining in a densely forested area the quality of the forest are also degraded. The forest cover density reduces and because of the various activities going in the area the forests are fragmented.
The Bellary district in Karnataka which has become infamous for its iron ore mining has suffered severe loss of agricultural land in the last decade. Between 2005-2010 nearly 43000 hectares of agricultural land was lost due to mining including some irrigated lands.

 Dr Patra Himansu Sekhar and Sethy Kabir Mohant[iv] of the Department of Geography of the Utkal University undertook a study to understand the impact on forests because of iron ore mining in Keonjhar through comparison of Satellite images of three periods - 1990, 2000 and 2012 provided insights regarding the changes in land use pattern especially in the forest land during these years.

The results of land use / land cover assessment were based on visual interpretation from satellite data. The land coming under forest refers to land with a tree canopy cover of more than 10 percent and area of more than 0.5 ha. Forests are determined both by the presence of trees and the absence of other predominant land uses within the notified forest boundaries. Forest was classified into three categories on the basis of crown density viz; dense, open and degraded. After observation of percent change analysis, it was found that maximum deforestation occurred in the vicinity of iron ore mining areas.

The dense forests exhibit crown density of more than 40%. Periodic analysis of dense forest shows that it covered an area of 5255.18 Ha (16.70 % of the total area) during 1990, 3123.67 ha (9.93 % of the total area) during 2000 and 1527.51 ha (4.85 % of total area) during 2012. Dense forest shows a decrease of 40.56 % in area during 1990 to 2000 while this decreased by 51.09%, between 2000-2012. It has been found out that most of the iron ore mining activities are taking place in the vicinity of dense forests because most of the iron resources are located with the hilly terrain covered with forest.

Therefore, decrease in the area of dense forests is attributed to the removal of trees to initiate iron mining activities and development of mining infrastructure. Open forest exhibit crown density in between 40% to 10%. It is easily identified on FCC image by its light red - pinkish colour, smooth - medium texture, contiguous to non contiguous pattern with irregular outline. Open forest covered an area of 3567.89 ha (11.34 % of total study area) in 1990, 5673.44 ha (18.03 %) in 2000 and 7430.88 Ha (23.62%) in 2012. Open forests exhibit overall increasing pattern by 59.01 % during 1990 to 2000 and 30.97% during 2000 to 2012. Similarly area under forest plantation category was found at 256.24 ha (.81% of total area) during 1990, which was reduced to 202 ha (0.64%) in 2000 and 179.17 (0.56%) during 2012. The land coming under land with shrub was 2707.24 Ha (8.60%) in 1990, 3808.63 (12.10%) during 2000 and 5810.32 (18.47%) during 2012.

This shows that it is not only the forest area that is lost for mining but the quality of forests is deteriorated when mining activity begins in an area with dense forests. It is estimated that over ten thousand hectares of forests would have been affected so far by iron ore, chromite and manganese mining in Keonjhar District alone.

The second example is from a study undertaken by Dr Mukesh from the Indian Instiute of Remote Sensing in Chhattisgarh. His assessment includes how not only forest areas are affected but adjoining agricultural lands are also severely affected. He found through his analysis of the Manendragarh area around 18.54% of the forest has been converted to barren lands followed by around 43.81% as degraded forest. The forest immediate near to the mining has been totally converted to non forest. However, a trend of impact of mining could be seen as gradient in the southern and northeastern side. The forest type is predominantly sal and sal mixed which harbours most the medicinal and rich species in the state. In the region very less area has been converted to agriculture, which could be help in concluding that major of the changes are due to mining activity. Further he found around 85.75 % of agriculture area has been totally changed to barren where as very least affected area is 13.30% of total agriculture.

While it is very difficult to assess the quantum of agricultural land involved in the total land degradation a sample survey undertaken by Sribas Goswami[v] and his colleague in the Raniganj coalfield indicates that agricultural land has generally been 18-55 percent of land degraded in a project. The quantum of agricultural land involved increases with mining entering into a relatively new area, whereas when the project is on an area where mining activities are already in full swing, the quantum of agricultural land involved may be smaller. A reasonable estimate may be that 35-40 percent of the total land involved may be agricultural land, which means around 10,000 ha of agricultural land involves in the Raniganj coalfield during the process of mining upto 2012.

Dr Nitish Priyadarshi who has been studying the impacts of mining in Jharkhand over decades points out that “Feeding minerals to meet the nation’s insatiable appetite has taken its toll on the state- rampant mining for decades has turned large tracts of forests into wastelands. During the 80’s, coal companies acquired thousands of hectares of forests in Jharkhand for mining operation in Damodar valley. In Singhbhum district a similar devastation of forest lands happened for extracting iron ore. According to the Forest Survey of India’s State of Forest Report, during an assessment published in 1997, Jharkhand had 2.6 million ha of forest. In 1999, it had 2.2 million ha, a loss of 0.4 million ha of forest cover. The forest cover in the Damodar valley coalfield, once 65 per cent, stands at only 0.05 per cent today.

Saranda, once so dense that even the sun’s rays couldn’t penetrate it, has Asia’s largest Sal (Shorea robusta) forests and is an important elephant habitat. Today, uncontrolled mining for iron ore, both legal and illegal, is destroying not just the forest, but also the wildlife, apart from the livelihoods of the local tribal communities. The impact on the forests has been significant. According to the state of forest reports, between 1997 and 1999, about 3,200 ha of forest were lost in the Singhbhum region. Between 2001 and 2003 some 7,900 ha of dense forests were lost in the East and West Singhbhum districts. Saranda too has been affected, and further degradation will have serious consequences for its considerable biodiversity[vi].”

Impact on Water

Open cast mining/quarrying /excavation not intersecting ground water table
Affecting natural surface water regime
Affecting ground water recharge regime
Open cast mining/excavation intersecting ground water table
Pumping of ground water
Declining of water table
Affecting natural surface water regime
Affecting ground water recharge regime
Affecting natural springs
Underground mining
Affecting ground water recharge regime
Shallow aquifers
Deep aquifers                      
Affecting ground water flow direction
Affecting ground water recharge
CBM/ Underground Coal Gasification
             Ground water resource/potentials-drying of upper aquifers
The impacts of mining on water occur from small scale quarrying to deep underground mining and in the new areas of Coal Bed Methane extraction and proposed Underground Coal Gasification. Mining and allied industries are major guzzlers of water and biggest destroyers of natural storage capacity and the most important cause for deterioration of water quality. The future of water resources is seriously at stake.

Water Forfeited to Mining from a part of Clearances Granted in 2007  (123 MINES)
Total Water Required (L)
per day
ML per yr
In an analysis of a cross-section of 123 mining projects which were granted environmental clearance by the Ministry of Environment and Forests in 2007, a startling 136 Million Litres Per Day has been forfeited for Mining that could serve the entire country for a day at the official rural norms for supply. If we were to extrapolate to all the mines in the country, water forfeited to mining operations each year would be atleast a week’s national actual consumption.

Considering that this is only consumption for mining operations, if we calculate the needs for downstream beneficiation and industries and at the permanent loss of aquifer storages, natural drainage systems and water rendered unusable by downstream pollution, the damage is colossal.

It is clear that intersection of water table by the mining industries must be considered seriously as in several places the major resources lies beneath the water table.  The breaching of the ground water table must be subject to stricter regulation as the very basis of survival of the local communities is sacrificed at this stage. Merely to say that the mine water is put to “gainful” use can lead to unsustainable management of the aquifer. While this may include several uses such as water supply to adjacent area, utilization for dust suppression by the industry, utilization by the mining industry for its different purposes, supplying to local communities, to water supply agencies, utilization for artificial recharge etc, it will be tantamount to mining water.

Water is used in coalmines for several functions including washing, spraying, in tailing -ponds and for coal preparation. This can cause a conflict with other water users and environmental requirement. Mines can dewater groundwater aquifers some distance from shafts or pits, which reduce the water table in the area adversely affecting other activities including agriculture. The major source of water pollution due to mining include pumped out mine water, spent water from coal handling plants, dust extraction and dust suppression systems, wash offs from overburden dumps, workshops and domestic effluents and effluents from washery. Chronic leaks from waste dumps or direct disposal of waste in the water bodies result in severe pollution of ground and surface water. Water pollution can affect the area even after the closure of the mine if the pits are not filled properly. Water in contact with the left over coal in the pits becomes toxic and unfit for any use. Also run off from abandoned waste dumps and pits, becomes acidic resulting in soil erosion, and contamination in the water bodies. Several examples of such pervasive impacts are seen in coalfields of Jharkhand, Orissa, West Bengal, Maharashtra, Uttar Pradesh, Madhya Pradesh, Maharashtra and Andhra Pradesh[vii]

In East Parej Open Cast Coal Mines operated by Coal India’s Central Coalfields Limited, which had the distinction of receiving World Bank Funds for Environmental and Social Mitigation, the land which used to be an agriculture land providing income and livelihood to people is now turned into a huge pile of dumps and pit holes. Such unkempt dumping without any proper topsoil conservation plan and regeneration action plan, leads to greater devastation of surrounding areas. Along with destroying the scenic beauty of the area, these huge piles of dump are destroying the regeneration capacity of Parej. The Environmental Management Plan has a provision of providing guarding sump around the over burden dump, so that any accumulation in these guarding sump can check waste or soil erosion from these dumps. In reality, CCL has not invested money or attention on these aspect. Mine waste collected during overburden removal is simply strewn and allowed to seep into underground water aquifers. Since mining started in the region, malaria incidence has increased.  Water resources in the region and wells provided to PAPs in Pindra and Premnagar blocks are found to be highly contaminated and unhygienic for drinking, and scarcity has aggravated the problem for them. People in Parej are left with no other option but to use these contaminated and unhygienic water sources for drinking and water collected in mine pits for bathing, resulting in higher rate of skin diseases in the region.  Mining operations in the region, apart from affecting the general surface structure of the region by means of huge overburden dumps and pit holes like lunar craters, is also disturbing the underground as well as stream flow in the region. This disturbance results into collection of water in mine sump or pit holes created by abandoned open cast mines instead of flowing into natural ponds or streams

Fortunately many of the coal deposits are not associated with pyrite and acid mine drainage is not a severe problem. However, there are a few mines with acid mine drainage problems, a significant example being the coal mines in Meghalaya. The Jaintia Hills District of Meghalaya is a major coal producing area with an estimated coal reserve of about 40 million tonnes. Sutnga, Lakadong, Musiang-Lamare, Khliehriat, Loksi, Ladrymbai, Rymbai, Byrwai, Chyrmang, Bapung, Jarain, Shkentalang, Lumshnong, Sakynphor are the main coal bearing areas of the District. The coal, in the area is found imbedded in sedimentary rocks, sandstones and shale of the Eocene age. The three coal seams vary from 30 to 212 cm in thickness. The main characteristics of the coal found in Jaintia Hills are its low ash content, high volatile matter, high calorific value and comparatively high sulphur content. Large scale denudation of forest cover, scarcity of water, pollution of air, water and soil and degradation of agricultural lands are some of the conspicuous environmental implications of coal mining. Besides, caving in of the ground and subsidence of land and haphazard dumping of coal and overburden has deteriorated the aesthetic beauty of the landscape. The water in coal mining areas has been found highly acidic. The pH of streams and rivers varies between 2.31 to 4.01. This indicates serious condition of the water bodies of the area that hardly can support any aquatic life such as fish, amphibians and insects. Contamination of Acid Mine Drainage (AMD) leads to acidity or low pH of the affected water bodies. Acidic water is a matter of primary concern since it can directly be injurious to aquatic organisms. It also facilitates leaching of toxic metals into the water that could be hazardous to aquatic life, directly or can disturb the habitat after precipitation. Most of the water bodies in the coal mining area of Jaintia Hills have been found containing high concentration of various metals. Many metals, though common, can be toxic to fish and other aquatic organisms thus reducing the overall fish population.  Besides, water was also found turbid and coloured due to suspended precipitates of iron hydroxides. Silt, fine sand, mud, coal dust and similar materials form a covering over the bottom and disrupt the benthic habitat. In addition they reduce the availability of oxygen and light for aquatic life. Dissolved oxygen is essential for sustaining higher life forms in water. It is an important parameter to assess water quality. Dissolved oxygen was found to be low in water bodies of coal mining areas, the lowest being 4.24 mg/L in river Rawaka and stream Metyngka of Rymbai.[viii]

Impact on Air Quality

Surface coal mining creates more air pollution problems with respect to dust than underground mining. An investigation was conducted by Prof Ghose and Dr Majee[ix] to evaluate the characteristics of the airborne dust created by surface coal mining in the Jharia Coalfield. Work zone air quality monitoring was conducted at six locations, and ambient air quality monitoring was conducted at five locations, for a period of 1 year. Total suspended particulate matter (TSP) concentration was found to be as high as 3,723 microg/m(3), respirable particulate matter (PM10) 780 microg/m(3), and benzene soluble matter was up to 32% in TSP in work zone air. In ambient air, the average maximum level of TSP was 837 microg/m(3), PM10 170 microg/m(3) and benzene soluble matter was up to 30%. Particle size analysis of TSP revealed that they were more respirable in nature and the median diameter was around 20 micron. Work zone air was found to have higher levels of TSP, PM10 and benzene soluble materials than ambient air. They concluded that more stringent air quality standards should be adopted for coal mining areas and due consideration should be given on particle size distribution of the air-borne dust while designing control equipment.

The Comptroller and Auditor General while evaluating the environmental situation in the iron ore mining area in Bellary found respiratory diseases have dramatically increased because of poor air quality. The problem with air quality in small stone quarries and crushers used for building materials has become a huge problem with a large number of workers suffering from the deadly disease of silicosis.

Brief Conclusion

The mining activities in India are causing severe ecological degradation and affecting health of workers and people around the mining areas. Unless stringent regulations are implemented, the damage will be irreversible. The ecosystems have only certain levels of resilience and when stretched beyond this, they cannot recover.

[i] Mining Matters – Environics Trust, 2012
[iii] Looking Back to Look Ahead: Green India 2047 edited by R.K Pachauri & P.V.Sridharan
[iv] Journal of Environmental Research And Development Vol. 9 No. 01, July-September 2014
[v] International Research Journal of Geology and Mining (IRJGM) (2276-6618) Vol. 4(6) pp. 154-162, September, 2014
[vii] Environics Trust, Water in Mining Areas, 2008
[viii] Sumarlin Swer & Singh O.P:Proceedings of the National Seminar on Environmental Engineering with special emphasis on Mining Environment, NSEEME-2004, 19-20, March 2004; Eds. Indra N. Sinha, Mrinal K. Ghose & Gurdeep Singh
[ix] Journal of Scientific and Industrial Research, Volume 62, September, 2003

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