/ 12 December 2006

Airport fuel spill: How it happened

Conservationists panicked when more than a million litres of jet fuel spilled out from OR Tambo International Airport and flowed into the Blaauwpan Dam, east of Johannesburg, in early November. As a result, small animals died and soil was contaminated.

It has been a month since the leak occurred and the area is still being rehabilitated, a task that may take ”a couple of years” and ”cost millions”, says the Airports Company South Africa (Acsa).

But while environmentalists rage against Acsa over the damage its alleged negligence has caused, losing 1,5-million litres — accounting for most of the two million litres of fuel spilled over 16 months — is nothing to Acsa when compared with the amount of fuel needed for aeroplanes and the amount that is stored in the ”fuel farm” (which stores hectolitres of fuel), said Musa Dlamini, Acsa’s environmental manager.

A class-E commercial aeroplane, such as a Boeing 747, can hold more than 240 000 litres of fuel.

The Mail & Guardian Online visited the airport to see how it was possible for so much fuel to end up in a dam 1,5km away.

Fuel is pumped into the tip of an aeroplane wing at 3 000 litres per minute from a refuelling point situated next to a valve chamber.

A ”fuel farm”, which is situated in a far-off corner of the airport, pumps hectolitres of fuel to nine such valve chambers, which in turn supply the refuelling points.

It was inside a newly installed valve chamber, situated on the section of the airport’s tarmac where aeroplanes park, where the leak started, but Acsa is still investigating the cause.

”Nobody can say whose fault it was. The gasket [part of the valve that connects two flanges together] could have been faulty from manufacturing. There are so many things to put in place: there’s the technician, there’s the support, the contractors,” said Dlamini.

What Acsa does know is that on the evening of November 7, a gasket inside the dark chamber pit, which contains a small network of pipes and manual wheels amid the stench of petroleum, broke. Fuel filled the 30-cubic-metre chamber within hours.

The fuel then flowed into ”sleeves”, which are holes on the sides of the chamber that connect other cables to the chamber.

Because the sleeves are connected to a service tunnel, which is in turn connected to storm-water pipes, the fuel rode on the water’s surface all the way to the protected wetland.

By the morning of November 8, a team of employees from pump company Rapid Allweiler, which was hired by Acsa, was working hard to build a temporary dam wall to block fuel from streaming into the dam. The team also pumped fuel out of the dam and took it to a recycling facility.

But by then the fuel had seeped into the soil below the dam’s surface, said Nicole Barlow, chairperson of the Gauteng Environmental and Conservation Association.

Speaking to the M&G Online, Barlow said: ”In 10 years, ecologists will still be feeling the effects of this spill. You can’t dig out the whole dam. Between 4 000 and 5 000 cubic metres of soil have been polluted.”

Acsa is currently performing tests to see how much damage has been done to the soil, but Barlow said Acsa will not make its report public.

The Gauteng Environmental and Conservation Association also spent R80 000 trying to save birds in the area. When it performed five autopsies on geese and ducks, the association found that the birds’ insides had been eaten away. ”The environment is totally toxic,” said Barlow at the time of the spill.

Dlamini said that ”obviously” the ducks died — fuel is carcinogenic and that if humans were to drink fuel, it would burn through their insides. But he adds that the spill was an accident.

”When there is an accident and someone gets killed, what can you do?” he asked, replying to a question about the charges of criminal negligence against Acsa from water-quality management — part of the Gauteng department of water affairs and forestry — as well as the Gauteng Environmental and Conservation Association.

Acsa is in the process of installing new sensors in the valve chambers that will detect large amounts of hydrocarbon in the chamber. If too much hydrocarbon is detected, ”the sensor will signal back to the airport’s headquarters and they will be able to shut down that section of the fuel line”, explains Dlamini.

In the meantime, it is conducting daily inspections of the valve chambers.

”I can’t imagine how such a thing could happen … it’s a new installation,” said Dlamini.