The Government is stepping in to tackle the massive task of cleaning up six sprawling landfill sites on the edge of the city, where years of uncontrolled dumping are threatening to lead to widespread pollution.
Although the scale of the problem is obvious, the precise nature of the job ahead remains unclear. Until now, rubbish at many of the sites has not been separated and contractors will face a toxic cocktail of medical, chemical, household, industrial, construction and agricultural waste.
At one site, they will even find themselves dealing with discarded military weapons.
At some of the dumps, which lack basic containment technology, potent liquid runoff is leaching deep into the surrounding soil, threatening groundwater resources.
“First, we have to know what type of waste we are dealing with,” said Majid al Mansouri, secretary general of the Environment Agency – Abu Dhabi (EAD), which has been charged with the job of rehabilitating the municipality-run landfill sites.
The first step will be taken next month, when consultants will be appointed to study the six sites and assess the pollution levels around them. That task alone is expected to take two months.
“We need to find the type of waste, how deep is the layer and the pollution to soil and groundwater,” said Dr Bader al Harahsheh, general manager of the Abu Dhabi Waste Management Centre, which runs the sites. “The data will help us to bring specialised companies to rehabilitate each site.”
The rehabilitation will not be easy or cheap. Part of the problem is the sheer volume of rubbish, to which the rapidly expanding city is adding all the time. This is compounded by the fact that Abu Dhabi has no large-scale recycling schemes, which means the sites contain a mix of waste from every possible source.
At 16 square kilometres, the largest site is Al Dhafra. In use for 25 years, Al Dhafra covers an area of land six times the size of the City of London. According to Mr Harahsheh, it receives an estimated minimum of 20,000 tonnes of waste every day.
An eight square kilometre site at Moqatra, some 80km away from the capital in Al Gharbia, handles 1,800 tonnes of municipal waste a day, in addition to 5,000 tonnes of rubbish from the construction industry, says Khaled Ali Ababneh of MBM-Dallah, the company that manages its operation of behalf of municipal authorities.
Mr Ababneh estimates that, at some locations, rubbish at the site could be as deep as 15 metres underground.
Original design inadequacies at many of the sites are blamed for most of the pollution problems the authorities are now facing.
“There is no lining system so this waste is causing pollution to the soil,” said Mr Harahsheh. In some cases, he said, run-off was seeping through the soil and contaminating groundwater.
According to the State of the Environment Report released by the EAD in 2007, while the larger sites offered “at least partly adequate disposal facilities”, the same could not be said for the smaller facilities. “Smaller settlements,” said the report, “lack appropriate treatment entirely. They are served by a number of smaller landfills that are not all managed properly. According to studies by consultants, performance at several landfills studied in the country does not match international standards.” The report also concluded that staff at the sites were “not trained or experienced in modern sanitary landfill practices” and faced occupational risks. Other problems included the “uncontrolled dumping of liquid and some hazardous wastes” and the fact that “groundwater resources are potentially threatened by pollution”.
One of several types of hazardous waste that will confront the clean-up teams is oil sludge. Oil companies have in-house treatment facilities, but some sludge is still disposed of at the sites. If this sludge seeps into soils, it can cause heavy-metals contamination. The EAD was now in the process of commissioning the design of a facility to treat such waste and other hazardous chemicals, said Mr Mansouri, and a consultancy for this project was expected to be appointed by September. Plans are also under way to organise the recycling of tyres and construction waste.
Besides contamination of the surrounding land, the sites are also responsible for air pollution, emitting large amounts of methane gas, which is released as organic matter decays.
Scientists say methane, a powerful greenhouse gas, is 20 times more potent than carbon dioxide in its contribution to global warming.
In many countries, such gas is captured and used as a source of energy. This is not the case in Abu Dhabi or the rest of the UAE.