September 5, 2001. Copyright 2001. Graphic News. All rights reserved.

Daring plan to drain volcano lake

LONDON, September 5, Graphic News: More than 40,000 people have been evacuated from their homes in the northern Philippines as part of a daring attempt to drain a lake in the crater of Mount Pinatubo.

Scientists fear that the crater -- which has filled during the rainy season to within two metres (6.5 feet) from its rim -- could breach and flood the surrounding area with millions of cubic metres of mud.

Raymundo Punongbayan, director of the Philippine Institute for Vulcanology and Seismology, said that a five-metre-wide (16-feet-wide) canal has been dug from just below the craterÕs edge.

During ThursdayÕs five-hour operation a high pressure hose will be used to blast through the lowest part of the crater, allowing at least 24 million cubic metres (5.3 billion gallons) of water to flow down the canal to rivers and then into the South China Sea, Punongbayan said. The evacuation of the town of Botolan and villages near the Pinatubo volcano is a precaution in case the operation goes wrong.

Vulcanologist Punongbayan said an early intervention would reduce risks of a disaster, but he warned there was a one in five chance of floods hitting portions of Botolan, 40 km (25 miles) to the west, if heavy volumes of water surged out of the crater.

If the operation goes wrong then around 50 to 60 million cubic metres (11-13 billion gallons) of water could come crashing down on the 12 villages near the volcano.

ÒThat may not happen but thatÕs how you have to think, about the worst-case scenario,Ó said geologist Kevin Rodolfo, a consultant of the British emergency agency Oxfam.

ÒImagine a lake with an area of 300 hectares (74 acres) and the water is 20 metres deep (66 feet). ThatÕs 60 million cubic metres (13 billion gallons),Ó said Rodolfo, who has been observing the volcano for weeks.

The problem began when the 1,745-metre (5,725-foot) high Pinatubo erupted in 1991, resulting in the deaths of 800 people. The volcanoÕs top was blown off during the eruption, leaving a hole covering five square kilometres (two square miles).

/ENDS
Sources: Philippine Institute of Vulcanology and Seismology, Associated Press, Reuters