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Abandoned mine behind highway collapse in West Bengal

an explosion in an abandoned underground coalmine tore through several homes in West Bengal's Burdwan district on January 16, 2007. It also caused cracks along a stretch of the National Highway 2 (that connects Kolkata to Delhi), disrupting road and railway traffic in the area.

The blasts happened in a coalmine near Asansol. Preliminary investigations found that the cracks along the highway developed due to subsidence in the area where an abandoned coalmine is located. Officials of the directorate general of mines safety, say, the explosion was probably caused by methane, a coal-bed gas, which had accumulated in the abandoned pit. The blast, in turn, collapsed underground pillars in the mines and caused the subsidence.

The mine, owned by Eastern Coalfields Limited (ecl), was abandoned in the 1960s but was not filled up with sand (a precautionary measure against subsidence).The pit was sealed in 2005 after a baby fell into it.

ecl has refused to take responsibility for the abandoned mines and blamed illegal mining for the incident. But Communist Party of India (Marxist) (cpi(m)) leaders, like district secretary Amal Halder, says, "ecl didn't pack the old pits properly with sand.' Local activists blamed the National Highway Authority (nha) for not testing the load-bearing capacity of the highway. The nha, in turn, says their job was limited to maintaining the highway and that road construction was the responsibility of the local public works department.

Land subsidence due to abandoned mines is an old problem in Asansol. Sipra Chakraborty, a social activist fighting to get the state government to make public maps of abandoned mines, said the problem arose due to improperly filled abandoned mines. "There are lots of gaps underground that need to be filled with sand, which, though not foolproof, is one of the basic safety measures when abandoning a mine,' says Chakraborty. "Yet, people are building homes and high rises on these lands.'