We investigate how an underground fire that has been burning for 100 years has led to one of India's largest land grabs.

Story highlights India is the third-largest producer of thermal coal after China

It is also the world's third-largest energy consumer after the US and China

Around 50 percent of energy requirements in the country are met by coal

A significant proportion of that production comes from the Jharia mines Sources: Coal in India

Underground fires have been burning for more than a century beneath India's largest coalfield, but in recent decades open-cast mining has brought the flames to the surface with devastating consequences for the local population.

As communities are destroyed and thousands suffer from toxic fumes, what lies behind this human and environmental disaster?

Filmmakers Gautam Singh and Dom Rotheroe went to find out.

The devastating impact of coal mining

After the US and China, India is currently the world's third-largest energy consumer; a position that is set to consolidate in coming years as economic development, urbanisation, improved electricity access, and an expanding manufacturing base all add to demand.

Right now much of those energy needs - up to two thirds of all electricity generated - are being met by domestically produced coal, of which India has abundant reserves.

A significant proportion of that production comes from the Jharia mines in Jharkhand state in the east of the country, which are also India's primary source of coking coal, an essential ingredient in steel production.

But the Jharia coalfields, which cover some 270sq km around the city bearing the same name, also pose a dreadful environmental and health challenge for hundreds of thousands of local inhabitants.

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Mining first began here under British rule in the 1890s but didn't really intensify until the early 20th century.

With that expansion came problems as new shafts were dug and others were hastily closed down as unproductive. In abandoned mines that weren't decommissioned properly, coal was left to spontaneously combust and underground fires began to spread.

The first blaze was detected in 1916 but by the 1980s more than 70 fires were under way. As these were often far underground they were difficult to suppress and were left to smoulder in the hope they might burn out, but by then India's increasing need for energy had begun to make itself felt.

In 1973 newly nationalised Bharat Coking Coal Ltd (BCCL), a subsidiary of state-owned Coal India, started large-scale open cast mining as a more rapid and cost-effective method of extraction.

However, as local activist Ashok Agarwal explains, that's also when the fires really took hold. "The idea was they'll get quick coal and they'll get cheap coal … but there was underground mining already done over here. So there were a lot of galleries - galleries are tunnels which these people make and they extract coal. So the ground of the galleries is always full of small pieces of coal and that catches fire. When you went in for open-cast mining where already underground mining has been done, you opened up the face of the galleries and then there was free flow of air inside and now you've got a massive fire."

The consequences were catastrophic. As the fires were exposed to the open air they spread, causing widespread environmental and health problems that have proved immensely difficult to resolve.

Coupled with the ecological damage done by open-cast mining, subsidence has made parts of the Jharia region like a moonscape, pockmarked with deep, smoking ravines from which billowing flames can often be seen.

At night the area is lit up with an eerie burning glow and the path of the advancing fires can be traced along the line of broken, smoking houses they leave in their wake. Every few months another village is snuffed out of existence as houses are hollowed into a smoking shell or gradually disappear into the huge cracks that open in the ground.

As disturbing is that the atmosphere is filled permanently with an acrid haze - evidence of the toxic gases such as carbon monoxide and sulphur dioxide that have made Jharia one of the most polluted places in the country and have caused respiratory problems and other serious diseases for thousands of people.

Dr Masoom Alam, a physician at a local hospital, sees the results every day. "People suffer from TB, wheezing, asbestosis, pneumoconiosis … And apart from these, there are skin allergies and rashes. Now with this open-cast mining they're blasting and exploding to extract coal and dust and toxins get widely spread which is having a very big impact, 99 percent of the people living here are affected. Then there are those fires which have their own impact and about which nothing has been done till now. Just imagine the amount of revenue generated by coal here, yet, despite the health hazards, people who live here aren't given any proper facilities. There has to be some kind of special initiative to safeguard their health."

Both the government and BCCL have attempted to resolve these problems over the years.

The company, for example, had made numerous attempts to douse some of the fires by attempting to seal them off and pumping in inert gases, but the operations have been hugely expensive and have had only limited success.

They have also devised compensation and rehousing schemes, managed through a body called the Jharia Rehabilitation and Development Authority, which could eventually involve moving up to 700,000 people out of the affected areas to newly constructed housing elsewhere. But in its first seven years only around 10,000 have been moved and many of those, often taken miles away from where they were earning their livelihood, complain bitterly about the inadequacy of their new accommodation and the absence of basic amenities, be they water and power supplies or jobs, schools and healthcare.

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It remains to be seen whether these issues will be overcome and settlements will eventually create their own source of livelihood and commerce, but there are also other groups in the area who have been affected, such as the peasant farmers who owned the land on which new settlements are being built, but who themselves now have nowhere else to go.

Yet as filmmakers Gautam Singh and Dom Rotheroe found when travelling through the area for this film, no one can foresee a time when coal production in the region will cease.

Indeed, the opposite is true. India's Prime Minister Narendra Modi has said he's keen to see an increase in the number of people being moved out of Jharia because that will make it easier to both douse the underground fires and open up access to further reserves of premium coal and give more Indians access to the energy they need.

But for activist Ashok Agarwal the consequences of that expansion for his fellow inhabitants - many of whom have lived here for generations - with be inescapable.

"Eventually Jharia will die. It is destined to die. The way BCCL is going on, they want to double the production by 2020. In that case more and more mining will be done here and many more villages will have to be shifted. So eventually this place is going to become absolutely desolate."

Source: Al Jazeera