Correction
15 Jan 2000
In a Research Review article in May (page 20, `Ashes to ashes, clumps to dumps'), we stated that the UK waste incineration industry produces 750 000tpa of fly ash, classified as hazardous waste owing to its heavy metal content. Mr W Prescott, technical director of Onyx Environmental in London, points out that, in fact, only 75 000tpa of ash is classified as hazardous, and this is because of its lime content. The ash contains only 1 per cent heavy metals.
