Former Siaolin residents dispute official findings of deadly disaster

TAIPEI: Former residents of a village that was buried by landslides last August have voiced anger over the official explanation given for the disaster, but authorities insisted yesterday that a tunnel project could not have caused the tragedy, as some of the survivors suspect.

Fan Liang-shiow, chairman of the Public Construction Commission (PCC), reiterated that the energy released during the explosions set off for the tunnel project was far weaker than the minimum needed to trigger a disaster.

The commission on Monday released a report on its investigation into what caused Siaolin Village in Kaohsiung County, southern Taiwan, to be buried by landslides during Typhoon Morakot last August.

The report fingered massive rainfall as the culprit that doomed the mountain village.

Siaolin absorbed 1,856mm of rainfall in 72 hours during the typhoon, triggering mudslides that covered the village and buried nearly 500 people alive.

Survivors and environmental protection activists believe, however, that explosions to build tunnels for the Tsengwen Reservoir water diversion project, as well as other factors including mass stockpiles at gravel yards and overlogging, were also behind the disaster.

They did not accept the report's conclusions, but Fan explained that a research team analyzed the explosion-triggered energy release in four fields from four perspectives: scientific theory, international experience, construction records and seismologic monitoring.

Based on its conservative calculations, the research team found that the energy released during the construction was far lower than the trigger point of 120 gal.

A gal, formerly known as galileo, is the unit of acceleration in the centimeter-gram-second system, equal to 1 centimeter per second squared.

Fan pointed out that although a blast of such a degree can be felt at a distance by people sensitive to tremors, it was not big enough to cause a disaster.

According to records on vibrations caused by construction in the area between December 20, 2006 - when the explosions began - and August 6, 2009, only 0.51 percent of the records showed figures higher than noise vibration standards set by the Environmental Protection Administration (EPA).

By comparison, 0.6 percent of the vibrations recorded between September 10, 2004 and December 20, 2006, before the blasting began, exceeded EPA standards, Fan said.

The figures show that the tremors caused by the project's explosions could not have caused a disaster.

Fan stressed that an evaluation by the Central Weather Bureau's seismologic monitoring station and US geologic surveys targeting tremors set off by dynamite also reached the same conclusion.

Meanwhile, when asked whether the suspended Tsengwen Reservoir water diversion project would be resumed, Fan said a PCC research team has suggested that the water channels be completed to prevent them from collapsing.

He added, however, that it would be up to the "Ministry of Economic Affairs" to decide whether the project will be restarted.

The project was launched to channel river water to the reservoir for agricultural irrigation.

China Daily/CNA

(HK Edition 02/03/2010 page2)