At least five people have died following a landslide at an illegal gold mine on Mount Pongkor in West Java, Indonesia, on Sunday 12 May 2019. The incident occurred in the at about 10.00 pm local time, following several hours of heavy rain in the area. Landslides are a common problem after severe weather events, as excess
pore water pressure can overcome cohesion in soil and sediments,
allowing them to flow like liquids. Approximately 90% of all landslides
are caused by heavy rainfall. Mine sites which leave soil exposed on hillsides are particularly vulnerable to such events, with the illegal mines around Mount Pomgkor, where local people simply dig into the hillside with handtools, having suffered a number of fatal landslips, with the most recent having occurred in 2015, when twelve people were killed.
Rescue workers near the scene of a fatal landslide at an illegal mine on Mount Pongkor, West Java, on the morning of 13 May 2019. Bogor Police/Jakarta Post.
Gold was first discovered on Mount Pongkor by the Antam mining company in 1981, with the company still running a large operation at the site. There are three major gold seems on the mountain, of which two run close to the surface, and therefore can be reached by both official miners working within the concession, and smaller, unlicensed operations outside. These unlicensed operations are notoriously unsafe, and also cause a variety of environmental problems associated with indiscriminate digging, with some mining haven taken place inside a national park.
Landslides are a common problem in Java, particularly during the Northeast Monsoon, which lasts from November to February, with peak rainfall in January and February, and can result in an annual
rainfall of around of 4000 mm in parts of Central Java. This problem has been made worse as expanding populations
has led to people farming higher on hillslopes, in an area where soils
tend to be volcanic in action and poorly consolidated (i.e. lack much
cohesion), making them more prone to landslides.
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