Monday 3 June 2013

Three workers killed in rockfall at Thai limestone quarry.

Three workers are known to have died following the collapse of a rockwall at a Thai quarry on Monday 3 June 2013, and another four are trapped beneath the rubble. The incident happened at the Phetsamut Quarry in Khao Yoi Disterict, roughly 110 km southwest of Bangkok. The rockfall is reported to have occurred after heavy rains associated with the onset of Thailand's monsoon season. The workers at the quarry are a mixture of Thai and Myanmar nationals. Some reports are putting the death toll as high as six.

Collapsed rocks at the Phetsamut Quarry in Khoa Yoi District. 3 June 2013. MCOT.

Thailand has undergone a major construction boom in recent years, fueling demand for limestone both as a building material in its own right and as the main ingredient in cement. Limestone is a common rock and relatively easy both to locate and extract, but doing this safely is slightly harder. Limestone deposits are often interbedded with softer sedimentary rocks such as clays. When these are exposed to precipitation they can be extremely absorbent, but as water is absorbed they lose cohesion and can be washed out, undermining the more resilient limestone layers and leading to rockfalls.

The approximate location of the Phetsamut Quarry. Google Maps.

Follow Sciency Thoughts on Facebook.