WHEN ABOUT 200,000 litres of furnace oil spilled into the Damodar river from the Bokaro Steel Plant on April 2, 1990, it took the authorities four days to wake up to the disaster. By then, the oil had travelled about 150 km downstream to Durgapur and for at least a week after the incident, the five million people in the area drank contaminated water. Even then, it was'nt the pollution control authorities who spotted the disaster. A downstream thermal power plant, which suddenly found its intake water for cooling its boiles totally unfit for use, raised the alarm.
The incident is not just a grim reminder of the hazards of industrial accidents -- it also draws attention to how the numerous industries that have mushroomed on the banks of the Damodar have polluted the river. There are more than 50 major and medium industries along the river in Bihar alone and more than 400 industrial units. Today, the Damodar is perhaps the most polluted river in the country. How did it earn such a dubious distinction?
The 563-km-long Damodar originates near Chandwa village in the Chhotanagpur hills in Bihar's Palamau district. It flows through one of the richest mineral belts in the world before draining into the Hooghly, about 50-km south of Calcutta. The Damodar valley has an area of about 57,000 sq km. Less than 8,000 sq km of this area is in the plains of West Bengal, where agriculture is an important activity. In the upper valley area, mining and mine-based industries are the dominant economic activity, with low agricultural productivity. In general, the region is poor in vegetation, the lack of which gets accentuated over the years. This, combined with the heavy mining activity in the area, has made the valley particularly vulnerable to soil erosion.
Industrialisation along the Damodar has rendered it a river of slurry. Minerals, mine rejects and toxic effluents are washed into the Damodar and its tributaries. Not surprisingly, today both its water and its sand are infested by coal dust and waste from the myriad industries that have sprung up in its basin.
The Damodar and its tributaries drain almost the entire coal mining area under the Central Coalfields Ltd (CCL), the Bharat Coking Coal Ltd (BCCL) and the Eastern Coalfields Ltd (ECL) -- three of the six subsidiaries of the public-sector Coal India Limited (CIL). The Damodar's catchment area also houses the Jharia coalfields. The Chhotanagpur region has sustained India's model of heavy industrialisation over the past 100 years. Most of the coal consumed by industries in the country comes from this belt.
The region is rich in other metallic and non-metallic minerals as well. It has substantial deposits of iron ore and bauxite. The upper valley -- parts of Hazaribagh and Giridih districts in Bihar -- supplies about 90 per cent of India's mica. Fire clay and limestone are also found in abundance in the upper valley area, particularly in the Palamau and Hazaribagh regions.
The average annual rainfall in the Damodar valley is about 1,400 mm, most of which occurs during the monsoon. On an average, there are 65 rainy days per annum although the delta plains receive more rain. This sometimes leads to floods and it was the devastating floods of 1943 that forced the authorities to set up the Damodar Valley Corporation (DVC). The command area of the DVC is about 26,000 sq km and three reservoirs have been set up, with flood control as the primary objective. But the corporation seems to have changed its priority and opted for power generation as its main objective because, according to Satyesh Chakravarty, a former professor of the Indian Institute of Management in Calcutta and an authority on the Damodar valley, the Centre made money for power generation more readily available. This has complicated problems as DVC's power plants consume a lot of the Damodar water and add to the pollution by dumping ash in the valley.
Indian industry's dependence on the region is evident in a simple set of statistics: Industry accounts for 91 per cent of the coal consumed in the country, 60 per cent of which comes from the Chhotanagpur belt. Increasing pressure to reduce India's dependence on petroleum products has resulted in increased coal production, which has risen from 17 million tonnes in 1972, when the coal industry was nationalised, to the current output of 230 million tonnes. Today, India is the fifth-largest producer of coal in the world. Similarly, three Steel Authority of India Ltd plants on the banks of the Damodar -- Bokaro, Durgapur and Burnpur -- account for more than 2.5 million tonnes of saleable steel out of the 7 million tonnes produced in the country today. Coal also provides for about 20 per cent of the transport industry's energy consumption requirements.
How heavily India depends on the region was made obvious when Jharkhand agitators called an economic blockade of the region in August 1992. In just one week, almost all industrial activity and rail transport in the country faced paralysis. Besides, the states of Bihar and West Bengal depend almost entirely on the area for their power requirements. DVC thermal power plants alone generate about 1,800 MW.
Today, ironically enough, it is the mineral wealth of the region that poses the biggest threat to the river. As Balram Bose, a professor in the water resources department of Jadavpur University, put it, "The moot question is: Will the river survive? I doubt if it can withstand the impact of the mining and industrialisation that are taking place in its catchment area."
Many DVC and CIL officials share this concern, but argue that degradation of the Damodar Valley and the heavy pollution are high prices that have to be paid for India's industrialisation. Many others disagree. Geeta Verma, a social worker associated with Gramya, an NGO working near Bokaro, asks: Is it fair to expect the Damodar and the people who live near it to subsidise the costs of Indian industrialisation?
Today, many parts of the Damodar and its tributaries look like large drains carrying black, highly turbid water. According to P Mishra, former chairman of the Bihar State Pollution Control Board (BSPCB), the Total Suspended Solid (TSS) count at most places along the upper and middle stretches of the river is 40-50 times higher then the permissible limit. For the most part, between Rajrappa in Hazaribagh district and Durgapur, the river has a film of oil and grease from industrial effluents. The Tenughat reservoir is a case in point. Its entire surface is coated with a greenish-yellow film, while its bed, according to the superintending engineer of the reservoir, C N Jha, is a mixture of coal dust and soil.
The crux of the problem is, of course, the mining in the area. Coal extraction began in the 1770s and has continued at an increasing pace. Most of the damage, as CIL technical director S K Ghosh points out, was caused by the numerous small mines that existed before the nationalisation of the industry in 1972. Now, many of the small mines have been merged to form larger mines. However, nationalisation of coal itself led to ecological destabilisation in a big way as production leapt up 14 times since 1972. Things don't bode well for the future either -- CIL is poised to produce 370 million tonnes of coal by the turn of the century.
With productivity of underground mines not keeping pace with rising demand, there has been a tendency to go in for large, open-cast mines. Today, about 60 per cent of the coal extracted from the area comes from these mines. However, these mines also happen to be the most serious sources of land degradation, and disposal of overburden -- rock and soil extracted with the coal -- is one of the biggest problems the coal authorities face. The total volume of the overburden, which is about 200 million cubic metres, is likely to be 500 million cubic metres by the turn of the century.
Chakravarty blames the mechanical extraction of coal as the major source of land degradation since the machines don't distinguish between coal and rock. The rock mined just adds to the volume of waste generated.
While Ghosh insists the overburden goes back into the mines after all the coal has been extracted, critics point out it takes years before a mine is fully exhausted and, meanwhile, the overburden contributes to the silt load of the river. Between Hazaribagh and Dhanbad, huge overburden deposits are placed so close to the river banks that, as Balram Bose of Calcutta-based Jadavpur University predicts, they may soon begin to choke the river.
Coal dust accumulation near mines, washeries and other coal-handling centres cause similar problems. Kameshwar Sinha, additional chief engineer of Dugdha Washery in Dhanbad district, admitted the biggest problem was how to dispose about one million tonnes of coal dust that has gathered in the vicinity of the plant over the past 15 years.
The other serious problem is the numerous coal-based industries of all types that have come up in the area because of locational advantages and the easy availability of water and power. Says Ghosh, "Because of the minerals and availability of cheap land and water here, coal-based industries were set up and a large number of them came up when effluent discharge was not an issue." Some of them are coal washeries, coke oven plants and soft coke batteries. In addition, the landscape is dotted with a number of other industries, varying from steel and cement plants to fertiliser and explosives plants. But what Ghosh does not mention is the industries that have come up recently, but have not performed any better in effluent treatment.
While the big plants in the public sector are gradually taking cosmetic steps at least to reduce the TSS level and other pollutants in effluents, the small private factories have no compunctions about discharging effluents into the open.
Among the big coal-based industries, 15 washeries account for the bulk of pollution in terms of TSS, oil and grease. The volume of coal the washeries handle varies between 3,000 tonnes and 8,000 tonnes per day and even though the exact volume of coalfine generated by the washeries is one of the best kept secrets of the coal authorities, sources say in certain plants, anything up to 20 per cent of the coal handled goes out in the form of slurry, which is deposited in ponds outside the plant. After the slurry settles in the pond, the sediment -- coalfine -- rich in calorific value is collected manually.
The amount of coalfine recovering as well as the oil and grease used in the washeries (see box) is, however, variable. Often, the water discharged into the river from the pond after coalfine is recovered carries high amounts of fine coal particles and oil. This happens either because the retrieval methods are inadequate or they are conducted before all the sediment settles.
The other major coal-based polluters are the coke oven plants that heat coal to temperatures as high as 1100oC in the absence of oxygen to prepare it for use in blast furnaces and foundries. The volatile components in coal are removed, leaving hot, non-volatile coke in the oven, which is washed with huge quantities of water and crushed after cooling. However, the water discharged after the wash contains oil and suspended particles.
Often, the effluents also carry toxic substances such as cyanide. For instance, Bharat Heavy Electricals Ltd's (BHEL's) pollution control research institute, which conducted a survey of some of the plants earlier this year, found cyanide levels in the effluents from the Lodna coke oven plant at Dhanbad to be as high as 0.54 mg/l, while the dissolved oxygen was "very low." Suspended solids, BOD and oil and grease levels were also found to be far in excess of tolerable limits. The Bararee plant in Dhanbad district was also found to be discharging effluents into a pond that was used by the people in the vicinity.
In this case, although only the TSS, oil and grease levels were above tolerable limits, many villagers complained the pond water often made them ill. "It is possible that the effluents are not adequately treated when the frequent power failures occur," says Gurdeep Singh, a professor at the Indian School of Mines' Centre for Mining Environment.
The other major polluters of the river are the seven thermal power plants in the Damodar Valley, three of which, with a combined installed capacity of about 1,800 MW, belong to the DVC. The first of these was set up by the DVC in 1952. It was also, incidentally, the first public-sector thermal power plant in the country. Because of the locational advantages, the electricity boards of Bihar and West Bengal also installed thermal power plants in the valley. The ash generated by all the power stations seriously affects the ecology of the area. To make matters worse, most of DVC's 14 units are outdated (three were set up in the early 1950s and seven in the 1960s). And, the less said about the state electricity board plants, the better. Former energy minister of Bihar Jagadanand Singh admits, "The state is barely able to run some of them, with the generation often being only a fraction of their installed capacity."
The plants consume between 3,000 and 8,000 tonnes of coal a day and as much as 50 per cent of the total solids generated is in the form of flyash. Yet, there is little effort to manage the waste. This is obvious from the fact that very few DVC units -- even though they are better managed than those run by the state electricity boards -- have electrostatic precipitators (ESPs). Of the six units of the DVC's Chandrapura Thermal Power Plant in Giridih district, only one has an ESP, while the others make do with old mechanical dust collectors. As these plants are located on the banks of the river, the flyash eventually finds its way into the water.
Disposing of the solid waste, or what is known as bottom ash, from boilers seems to degrade the river even more. The bottom ash is supposed to be mixed with water to form slurry which is then drained into ash ponds. However, most of the ponds are full and in several cases, the drainage pipes are choked. So the slurry is directly discharged into the river.
At Chandrapura, for instance, only two of the six units are functioning and the slurry discharge pipe of one of the units has broken down. S P Guha, chief engineer of the plant, admits they "were temporarily forced to dispose of the ash slurry directly into the river". According to T Singh, senior divisional engineer, once the generation in a unit trips, the slurry gets deposited in the disposal pipes and chokes them. Until the pipes are cleaned, "there is no choice but to directly discharge the ash into the river". He, however, concedes choked pipes are common because of poor maintenance.
Sources point out the breakdown of disposal pipes is so big a problem the DVC has been forced to award expensive maintenance contracts. Even BHEL's pollution control research unit found the TSS levels in the discharge at all the power plants it surveyed higher than prescribed limits -- in one of the drains of the Chandrapura plant, the TSS was as high as 22,629 mg/l, while at Jamadoba it was above 7,000 mg/l. It also found several overflowing ash ponds.
The most disturbing consequence of the Damodar pollution is its effect on the people who live in its vicinity. The river and its tributaries are the largest sources of drinking water for the huge population that lives in the valley. When the Bokaro spill occurred, the water from the river that the people drank was clearly unfit for human consumption, with oil levels 40-80 times higher than the maximum permissible value of 0.03 mg/l. "They had no choice in the matter, since the groundwater levels in the area are very low," says Gurdeep Singh. An official of the Jamadoba Water Works, which supplies water to nearly two million people in the coal-mine area, points out, "We have to give water to the people and this is the only water we have. We couldn't have let the people die of thirst saying the water was polluted."
A majority of even the urban population of more than 3 million in Bihar and West Bengal is supplied this water after it is treated with lime and chlorine. Needless to say, a large population of the people in the rural areas don't have the luxury of treated water.
Urban dwellers outside the industrial townships are bereft of clean water. Municipal water supply is practically non-existent in most areas and the only source of water for human and cattle consumption is that of the Damodar and its tributaries, regardless of their quality. In Gomia, people living just outside the pampered Indian Explosives Limited (IEL) township depend on water from the Konar, a tributary of the Damodar. According to a worker of the Asha Seva
|Grass violations of effluent dischage limits|
|Effluents||TSS||Oil and Grease||BOD||COD||Cyanide|
|Lodna coke oven plant||165.0||16.3||41.0||212.0||0.54|
|Bhowra coke oven plant||7018.0||24.3||44.0||112.0||0.19|
|Chandrapura thermal power plant(drain 4)||22629||1.6||16.6||6480|
|Bokaro steel plant(Drain 1)||665||18.1||30.6||83||0.09|
|Sudamdih coal washery||3950||4.0||22.0||34.0|
|*Bureau of Indian Standards tolerance limits for industrial effluents discharging into surface waters.|
|TSS: Total suspended solids|
|BOD: Biological Oxygen Demand|
|COD: Chemical Oxygen Demand|
|Source: Pollution Control Research Institute|
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.