Indonesia's solution to a relentless mud volcano - giant concrete balls
Scientists in Indonesia are to start dropping huge concrete balls chained together into the mouth of a mud volcano today in a desperate attempt to staunch a relentless flow that has wiped out villages, factories and vast tracts of farmland.
The operation to lower 2,000 of the balls, chained together in groups, into the mouth of the rupture has been postponed several times. But the gantry is now in place to allow the operation to begin. However, British experts who have closely monitored the mud volcano, known locally as Lusi, are sceptical that the effort will halt the outpouring of noxious gas, mud and boiling water that has been spewing at a rate of a million barrels every day for nine months.
They fear that the pressurised underground reservoir responsible for the sludge that has inundated four villages and 25 factories near Indonesia's second city, Surabaya, will find other fissures to the surface in possibly more dangerous or difficult areas.
Professor Richard Davies, a mud volcano expert at Durham University who is visiting the site, has said that the eruption was almost certainly triggered by exploratory drilling for gas, rather than an earthquake several days earlier.
The findings directly contradicted the assertion of Indonesia's welfare minister, Aburizal Barkie, who said it was "natural disaster". His family controls PT Lapindo Brantas, the drilling company at the centre of the environmental scandal that has left 11,000 people homeless.
The operation to lower the concrete balls, each weighing up to 400kg (63st), into the rupture will start slowly at first. The hope is to drop the ball and chain set to a depth of 100 metres (330ft) with the aim of slowing the flow by up to 70%.
Lapindo Brantas initially tried to staunch the flow by pumping mud and concrete into the mouth of the volcano. Eventually the pressure of the mud burst from fissures around the plug.
The Indonesian government has ordered Lapindo Brantas to pay Â£220m in damages, including Â£145m to the victims of the disaster.
The hope is that the chained balls will move together and be more likely to lodge in a place where the friction will reduce the mudflow that has already covered an area of four square miles to a depth of 10 metres.
But Richard Swarbrick, of Durham-based consultancy GeoPressure Technology, does not believe the strategy will solve the problem of the mudflow that could eventually cause the earth's crust to buckle under the weight. "I have no doubt that if the balls remain at a reasonable level they will slow the flow," he said. "The risk is that if you check the event you will force the water and mud to come out somewhere else."
Indonesia's solution to a relentless mud volcano - giant concrete balls | Special reports | Guardian Unlimited