Potentially deadly asbestos waste was being dumped at a landfill site in Northern Ireland as recently as last year, it has been revealed.
Lisbane Landfill in Co Armagh only ceased accepting the waste in June 2013, according to Environment Minister Mark H Durkan.
Described as a hidden killer, asbestos can lead to serious illnesses such as lung cancer and mesothelioma, and is therefore designated as hazardous waste.
Disposing of hazardous waste alongside normal waste was banned from 2004 under the EU Landfill Directive 1999.
After that it could only be disposed of after suitable procedures were agreed with the Northern Ireland Environment Agency. One site – Lisbane, near Tandragee – had accepted hazardous waste, but stopped doing so last June.
The details were revealed by Mr Durkan after an Assembly question from Green Party MLA Steven Agnew.
He requested a breakdown of sites where hazardous waste was dumped after it emerged that radioactive waste had been dumped at sites in Belfast and Londonderry in the 1980s.
The "controlled burials" emerged in papers released under the 30-year rule by the Public Record Office last month, and are being investigated by the DoE.
Mr Agnew said hazardous waste remained a threat to human health and the environment for many years.
"Burying it simply means 'out of sight, out of mind' – but its potential to contaminate land or even the water table lingers for decades," he told the Belfast Telegraph.
"The issue of asbestos, once deemed to be safe enough to put into people's homes, highlights how we must exercise great caution going forward in what chemicals and hazardous substances we expose both humans and the environment to.
"We need to make sure that best practice guidelines for the disposal of asbestos are followed rigorously and these areas are carefully monitored by the DoE for any threat of future contamination."
Responding to Mr Agnew's question, Mr Durkan said premises that accumulate and dispose of radioactive waste must have a certificate of authorisation issued under the Radioactive Substances Act 1993.
One of the routes for the disposal of low level solid radioactive waste was via controlled burial in landfill sites.
This took place at two locations – Culmore Point in Derry and Duncrue Street in Belfast.
Asbestos is a naturally occurring fibrous substance used extensively in the UK building industry between the 1950s and mid-1980s. If asbestos isn't damaged then there is little risk to health. But once disturbed, it breaks down into fibres up to 1,200 times thinner than a human hair. When inhaled, the fibres can cause lung cancer.