The discovery of asbestos in topsoil accidentally brought to Stonehenge during site renovations is another reminder of the continuing risk of exposure three decades after the substance was first banned in Britain. According to one report, “there were significant lumps of it, about the size of a brick…”

Many might be surprised that asbestos can still find its way into the topsoil used by contractors to return to chalk grassland a section of the A344, which runs past the English Heritage site in Salisbury, Wiltshire.

The report has only just surfaced that asbestos was actually uncovered in 2014 during landscaping work at the new £27 million visitors centre, which opened in 2013. English Heritage expressed their serious concern and disappointment that the contractors failed to provide topsoil which met the required standards, and the material was removed within days.

The potential toxic risk to the 5,000 year old monument site follows a similar incident during a modern era development at the London 2012 Olympics.

Similar incident

Three months before the opening ceremony, an environmental campaign group brought to court their complaint over an Olympic basketball training facility. The unit was to be built on parkland at Leyton Marshes, north London, which was said to be a post World War Two ‘land-fill” site contaminated with lead and asbestos.

Local residents were concerned over the proposed ground disturbance and the potential health risk. Significant quantities of hazardous asbestos-containing materials were believed to be mixed in with the soil, rubble and debris from landfill dating back to the 1960 and 70s period of peak asbestos use.

The question of how asbestos waste comes to still be used by contractors may be simply due to a combination of possible negligence and the legacy of Britain’s industrial past.

Asbestos-containing materials can still be left behind

There was limited information and a widespread lack of asbestos awareness to the deadly health risks of developing fatal mesothelioma and asbestosis diseases across many of Britain’s industries, such as construction and manufacturing. From the 1940s through to the end of the 1990s a total of 5.3 million tonnes of asbestos was imported into Britain. When old factory buildings, foundries, mills and engineering workshops are demolished, asbestos-containing materials can still be left behind in the ground.

It’s not just the sites of former factory premises with possible asbestos-contaminated soil. More than over half of all Britain’s residential development occurs on re-used sites, which now commonly takes place on “contaminated” land.

In addition, the absence or the non-compliance with asbestos disposal regulations can sometimes lead to demolition waste being sent to landfill sites and can still be found long after the landscaping over of a site to create a parkland amenity has been carried out.

Negligent recycling

The delivery of asbestos-contaminated landfill topsoil to Stonehenge could have possibly occurred due to negligent recycling, which simply went unchecked. The careful grading of demolition materials for recycled use as bulk fill hardcore or general filling aggregate is usually carried out under authorised waste management on-site or at a licensed Waste Transfer Station.

The Environmental Permitting Regulations (EPR 2007) in England and Wales sets out the necessary requirements for crushing, grinding and other size reduction operations and no contaminated materials, such as asbestos should be processed.

In addition The Hazardous Waste (England and Wales) Regulations 2005 require that any waste having an asbestos content greater than 0.1 per cent is classified as ‘Hazardous Waste’, while less than 0.1 per cent can be classified as non hazardous – unless there are other contaminants present which would classify the waste as hazardous. Asbestos fibres present in concentrations greater than 0.001per cent are considered a health risk and must be dealt with as “hazardous soils” for disposal purposes.

Currently, the Joint Industry Working Group (JIWG) is planning to issue its Code of Practice Guide to Asbestos In Soil and Construction & Demolition Materials.