Naturally Occurring Asbestos (NOA)
Asbestos is a mineral that comes from the ground – it is commercially mined and refined and turned in to different types of products known as Asbestos Containing Materials (ACMs). Asbestos bans are gradually being implemented across the globe, and so the mining of this deadly mineral is starting to subside. However, there remains the issue of interfacing with Naturally Occurring Asbestos (NOA) when undertaking large infrastructure projects where ground works and particularly tunneling are required. By digging, tunneling and blasting into the ground and rockfaces, Asbestos mineral fibres can be released into the atmosphere in large quantities and could affect the health of those involved in the immediate work, as well as those of the people within the vicinity. Contaminated land can be a resultant issue, that can cause future liabilities.
When Asbestos is found as a natural component of rocks and soil, this is when it is classified as NOA. Typically, the content of Asbestos is anywhere between <1% and 25% - far less, than when it has been refined by the Asbestos producing factories that sell this material. That said, it still has the potential to cause harm to human health. Even in locations where deposits are not significant enough for mining, Asbestos can be found all over the world - from the West Coast of the USA (California), to the Asbestos mountains of South Africa. Huge amounts of Asbestos are currently being removed from the operational mines found within Kazakhstan. In the Middle East, reviews of geological reports have found that Asbestos can be found within the mountains of Oman, rockfaces of Fujairah, and the even hills of Hatta in the Emirate of Dubai.
If the NOA is not disturbed, then it cannot pose a hazard to human health. However, through natural weathering, and more concerningly through the development of major infrastructure projects (roads, railways, tunnels etc.), Asbestos can be significantly disturbed, and people’s wellbeing can be put at risk. Companies and individuals involved in blasting, drilling, rock cutting and tunneling are those that are most at risk, and control measures and safe systems of work should be in place to protect them and others in the proximity of the works.
Asbestos testing will be required and samples of the rocks should be collected to test to see whether Asbestos fibres are present. This will require core samples to be taken and the mineralogy of the samples analyzed to see if Asbestos fibres are present.
Asbestos Management During Works
If Asbestos is found, then strict control measures should be implemented to deal with any potential Asbestos risk. All companies involved on the works should be provided with Asbestos awareness training as a minimum. If it is a must that the Asbestos is to be disturbed, then to minimize the fibre release then the rock face and resultant debris should be constantly dampened down using industrial scale bowsers and wet sprayers. Activities that minimize dust release should be utilized (i.e. cutting over blasting) and where possible where Asbestos is encountered works should be stopped until the Asbestos abatement can take place. Workers should be provided with protective equipment (PPE and RPE), decontamination showers should be present on site, and waste rubble that could contain Asbestos should be appropriately managed (by covering and potentially burying/disposing of as Asbestos waste – soil remediation may be required). Walls of the tunnels/cut outs should be coated to encapsulate any exposed rock faces.
An Asbestos manager should be appointed for the project to manage the Asbestos risk. To accompany the works, all of the high-level measures listed above should be underpinned in a project specific Asbestos Management Plan (AMP), with much more detailed information within the AMP on legislative requirements, roles and responsibilities, control measures and an Asbestos action plan. During all the works, Asbestos air monitoring should be conducted around the perimeter of the works, at the work site and to the workers involved in the project to assess the environmental and occupational levels of Asbestos in the air.
If you have any Asbestos related concerns, contact us to see how Anthesis Consulting Middle East can help you:
Charles Faulkner (Head of Environment, Health and Safety and Asbestos Team Leader)
Phone: +971 (0) 50 5541 320
Email: asbestos@anthesisgroup.com