Incinerators in the UK create almost a million tonnes of ash every year. The ashes, which are contaminated with heavy metals like lead and cadmium as well as toxic compounds like dioxins, are usually deposited in
landfills leaving a toxic heritage for future generations. These pollutants can leach out posing a more immediate threat to ground water and rivers.
The highest concentrations of pollutants are in residues from the pollution control devices. These residues are supposed to be sent to “special waste” landfills but it has recently emerged that the Byker incinerator in
Newcastle has been illegally mixing this “fly” ash with other ashes. This toxic mixture was spread on allotments and paths in Newcastle. Mixed fly and bottom ash from Edmonton incinerator has also been used to build roads in London and a car park in Peterborough. The practice of mixing ash with aggregate or asphalt for use in construction is increasing.
It allows incinerator operators to avoid disposal costs as well as generating extra income, but even when used in ‘bound applications’, erosion will eventually release the heavy metals and dioxins into the environment and workers may be at risk of exposure to dioxins and metals in dust particles. Ash residues from the gas cleaning filters of incinerators are classified as hazardous waste and should be disposed of in special landfills. According to the European Environment Agency “the disposal of filter dust/ fly ash
from waste incineration plants is a serious problem”. Filter ash contains very high concentrations of heavy metals and chlorinated organic compounds, which can cause cancer and other health problems.
The above was taken from: http://www.greenpeace.org.uk/MultimediaFiles/Live/FullReport/3809.PDF