Jharia Coalfields (JCF):
It is one of the most important coalfields in India, located in Dhanbad district, between latitude 23� 39′ to 23� 48′ N and longitude 86� 11′ to 86� 27′ E. This is the most exploited coalfield because of available metallurgical grade coal reserves. Mining in this coalfield was initially in the hands of private entrepreneurs, who had limited resources and lack of desire for scientific mining. The mining method comprised of both opencast as well as underground. The opencast mining areas were not backfilled, so large void is present in the form of abandoned mining. Extraction of thick seam by caving in past at shallow depth has damaged the ground surface in the form of subsidence and formation of pot holes or cracks reaching up to surface, enhancing the chances of Spontaneous heating of coal seams and mine fire. This coalfield is engulfed with about 70 mine fires, spread Over an area of 17.32 sq. km., blocking 636 million tonnes of coking coal and 1238 million tonnes of non-coking coal. Around 34.97 sq. km. area of the JCF is under subsidence. It is mentioned in JCF reconstruction program that 70% of the underground production of coal would come by caving and balance 30% by stowing and thus about 101 sq. km. underground mining area would be affected by subsidence. The other factor, which damages the land in JCF, is opencast mining and overburden dumps.
Raniganj Coalfield (RCF): Raniganj Coalfield, where the first coal mining in India was started in 1774, is situated mainly in the Burdwan district of West Bengal. Large coal bearing areas in this coalfield is blocked underneath surface properties. The situation here is further aggravated due to the presence of old abandoned water-logged areas, caves and caved areas. The subsidence in this coalfield is also responsible for mine fire. The total fire area in RCF (within the basin) is 5.88 sq. km. While the subsided area is 29.4 sq. km. In the near future also, as more and more coal is to come from underground method, more area is likely to be degraded due to subsidence. The presence of old and water logged working is the major problem in this coalfield. There are some localities, which are situated above the water logged (unsafe residential) areas. Overburden dumps and open pits also increased the problems of land degradation.
The Jharia coal field fire
The Jharia coalfield in Bihar is an exclusive storehouse of prime coke coal in the country, consisting of 23 large underground and nine large open cast mines. The mining activities in these coalfields started in 1894 and had really intensified in 1925. The history of coal-mine fire in Jharia coalfield can be traced back to 1916 when the first fire was detected. At present, more than 70 mine fires are reported from this region.
Coal, a non-renewable source of energy, is found in several parts of the world. The coal layers are mined by two methods: open cast mining and underground mining. Coal is formed from organic matter with a high carbon content, which when exposed to certain conditions (temperature, moisture, oxygen etc.) tends to ignite/ burn spontaneously at rather low temperatures. This may occur naturally or the combustion process may be triggered by other causes.
However, once a coal seam catches fire, and efforts to stop it an early stage fail, it may continue to burn for tens to hundreds of years, depending primarily on the availability of coal and oxygen. Coal fires have occurred in nearly all parts of the world like India, the US, Indonesia, South Africa, Australia, China, Germany and many other countries. However, the nature and magnitude of the problem differs from country to country. In India, the fire in the Jharia coalfield has mainly been due to unscientific mining and extraction of coal in the past.
Fires may occur in coal layers that are exposed to the surface of the earth or areas close to it. These are visible to the naked eye. Also, fires erupt in the underground seams, which have large cracks that serve as channels for oxygen to the burning coal. The main cause of natural coal fires are lightening, forest fires, bush fires, etc. Among human causes are accidents, negligent acts, domestic fires, lighting fires in abandoned underground mines for heating or distilling alcohol etc. Besides, burning away of an important energy resource, it creates problems for exploitation of coal, poses danger to humankind, raises the temperature of the area, and when present underground, can cause land to subside.
The pollution caused by these fires affects air, water, and land. Smoke, from these fires contains poisonous gases such as oxides and dioxides of carbon, nitrogen and sulphur, which along with particulate matter are the causes of several lung and skin diseases. High levels of suspended particulate matter increase respiratory diseases such as chronic bronchitis and asthma, while the gases contribute to global warming besides causing health hazards to the exposed population. Methane emission from coal mining depends on the mining methods, depth of coal mining, coal quality and entrapped gas content in the coal seams. These fires also pollute water by contaminating it and increasing its acidity, which is due to a certain percentage of sulphur that is present in coal. These fires lead to degradation of land and does not allow any vegetation to grow in the area.
The measures for controlling coal mine fires, in the case of Jharia coalfields, include bull dozing, leveling and covering with soil to prevent the entry of oxygen and to stabilize the land for vegetation. Fire fighting in this area requires relocation of a large population, which poses to be a bigger problem than the actual fire fighting operations.
Rehabilitation of Jharia Coalfields’ People
The Government has conducted various studies to know the cause of fire and subsidence of area in and around Jharia Coalfields from time to time. In January, 1976 a committee under Chairmanship of Joint Secretary, Department of Coal and Ministry of Energy was constituted to examine the safety in Nationalised coal mines and the committee made certain recommendations for measures to control danger due to subsidence. Directorate General of Mines Safety (DGMS) had also identified a number of areas which required attention due to problems of fire and subsidence. A World Bank funded project namely Jharia Mine Fire Control Technical Assistance Project was also taken up to address the issue of fire control. In December, 1996 Government of India had constituted a High Power Committee under the Chairmanship of the then Secretary (Coal) with other members from the Govt of Bihar & West Bengal, Planning Commission, DGMS, Ministry of Labour, Chairman CIL, CMDs of ECL, BCCL & CMPDI with Director (Tech), MOC as member secretary to review the problem of fire & subsidence in Jharia and Raniganj coalfields and suggest measures to deal with problems of existing habitation on subsidence/fire prone areas. Based on the recommendations of the Committee a Master Plan was prepared to address fire problems, subsidence, rehabilitation and diversion of surface infrastructure from endangered areas. Subsequently, Government has approved the Master Plan in August, 2009 for addressing the issues of fire, subsidence, rehabilitation and diversion of surface infrastructure in Jharia Coalfields (JCF) and Raniganj Coalfields (RCF) for an outlay of Rs.7112.11 crores for JCF and Rs.2661.73 crores for RCF for implementation in 12/10 years respectively.