Mount Merapi remains dangerous

Tarko Sudiarno, The Jakarta Post, Yogyakarta

Yogyakarta Volcanology Observation Agency renewed its warning to sand miners and climbers of the possibility of a major outburst of hot lava and steam from Mount Merapi in the coming weeks, due to the rainy season.

Chief of the observation agency Ratdomopurbo said workers quarrying sand on rivers in Magelang regency should stop their daily activities for the time being, people living on its west slope should remain alert and mountain climbers should also not venture any closer to the crater because the mountain's new crater could spew out hot lava due to continued rain at its summit.

"The warning is renewed because the mountain has spewed out hot lava and steam six times over the last week and the rainfall surrounding the mountain is increasing," he said after presiding over a meeting to monitor the mountain's activities here on Monday.

The outflow of hot lava and steam was caused by a heavy downpour that destroyed the new crater's mouth, or upper part. "A one-hour-long heavy downpour would be enough to cause a landslide on the mountain, bringing down hot lava and steam," he said.

The lava that spewed out last week did not cause any human fatalities because it spread only two-and-a-half kilometers away from the crater.

Ratdomopurbo acknowledged the mountain's activity was not increasing but said a potential danger was raised by the downpour that had inundated the new crater, causing a strong buildup of pressure inside that had spewed out the lava.

The new crater, which developed last year, contains 100 million cubic meter of hot lava, and around 20 percent of it was spewed out last week, he said.

He said his office has given information on the mountain's lava to all people living and working in the upper part of the rivers Senowo, Lamat and Sat in Magelang regency because the crater faced the regency.

The 2,875-meter-high mountain located in the border area between Yogyakarta and Central Java also spewed out hot lava in 1994, killing dozens of villagers in the regency.

It has erupted hundreds of times since 1006, when it claimed thousands of lives. It erupted for the first time in 1006, killing half of the province's population. Some 3,000 were killed in the second eruption on Aug. 4, 1672.

It also erupted five times in the 19th century and six times in the 20th.