Dhanbad town exists for one reason: coal. This much becomes quickly clear to me. A fine layer of coal dust covers everything in the hotel I have put up in, and the manager has assumed I have something to do with the coal business. Why else should I have come to Dhanbad? I tell him I am not interested in coal, but in the river Damodar.

Damodar? But that's also full of coal. Touché. He smiles: so you will be going to the Telmucho bridge? I nod. He nods, too. It seems all pollution people, as he puts it, go there.

Telmucho bridge is an hour's ride from Dhanbad. A minute out of town and I am passing coalfields. Dhanbad is on the edge of the Jharia coalfields.
It sprawls over 450 square kilometres (sq km) and is one of India's biggest coalfields. A few more minutes and I pass a BCCL (Bharat Coking Coal Limited) housing colony. Its inhabitants have been asked to evacuate their houses because underground mine fires have come too close for comfort.

From the bridge the river looks choked. On either side of the main channel, as far as I can see, there are huge heaps of loosely dumped earth. These heaps are called the 'overburden', the upper layer of soil and rock removed in open-cast mining to get to the coal below. Perched precariously, they certainly seem to overburden the river - it requires a mere gust of wind for some clods to freely tumble into the water; how must it be like when it rains heavily, as it does in this region? In open-cast mining, a massive pit is dug and coal removed from the bottom, the pit being as much as a km wide. This way of mining is considered more efficient in terms of the coal freed, so more and more older deep mines are being converted to open pits. The volume of overburden is at least as much as the amount of coal mined; in Jharia alone, it now accounts for 4.5 sq km of raw soil and rock.