This webinar will feature two presentations:
- In the first presentation, David Coll will cover the legacy of Asbestos in soils including the nature of asbestos, why it is found in soil, when exposure may be possible and the legislation surrounding asbestos.
- In the second presentation, Mathew Hussey will seek to explain what impact asbestos in soils may have on you and your business, from an insurance perspective.
In areas of heavy industrialisation and in much of the post war building projects asbestos containing materials were used extensively. It is estimated that around 4 million domestic properties and 1 million commercial properties have asbestos containing materials in the UK.
Asbestos can be found in soils from the natural breakdown of rocks but it is mainly from the widespread use of material that has been spread inadvertently, particularly before its health effects were well understood. This is therefore often the case at “brown field” sites. Poor demolition practices, burying or capping of waste on site and fly tipping of materials has spread asbestos throughout our environment. Ship yards and large commercial sites managed their construction and product waste in the most efficient manner possible way and often, prior to regulations this meant the material was disposed of at the site.
Asbestos construction contamination is often found with a range of other contaminants from hydrocarbons to heavy metals and even alongside ecological issues such as Japanese knotweed. These makeshift dumps were used for any materials that needed to be cleared away for progress to take place.
Typical background levels in soils are at present unknown as few studies have been performed. Similarly, the risk posed by such materials is also unknown as it is difficult to establish a link between fibres in soil and fibre release to air. The concentration of asbestos materials will vary from product to product and from site to site. The worst cases are often where loose insulation has been manufactured and has spilled into the site, but it can also be as a consequence of crushing up of asbestos cement materials to make bridle paths and the like.
Despite legislation to prevent spread and exposure it is a matter of fact that there are numerous examples where the material has been dispersed far and wide and there has clearly been a failure of these control measures. Outdoor dilution factors and the nature of our weather tend to make high exposures unlikely. However, once we carry the material in from the outdoor space and dry it out we can start to expect small and persistent exposures to occur. This is a particular problem as the earlier the exposure in life then the greater the affect of health issues. Onset of an asbestos condition takes around 15 to 40 years so an exposure for an 80 year old gardener and a 2 year old toddler, although equally sad possibly mean at one end of the scale a life cut short in their teens! The legislation is there however to punish the perpetrators of any uncontrolled exposure and ignorance of the effects of contaminating the environment is not a defense. Most asbestos related interventions are due to lack of management and often will result in an improvement notice recommending that asbestos materials are identified and are then appropriately managed.
Who will be held responsible for the exposures from soil is difficult to establish. It can be the originator of the contamination – if they still exist and the incident can be proven. It can also be the land owner who at the very least will be held responsible for managing the risk from their property. Finally it can also be the consultant who failed to identify the material or the contractor who has started to dig without proper investigation.
Asbestos, because it is inert, is difficult to find when in localised hot spots. It doesn’t migrate through the soil so the grid method of site investigation can miss it even though every effort has been made to locate it. It can be deposited at a site during new builds from contaminated fill from other sites too, so what was not there at the start of a project can be found later on.
It is important to note that the methods for determination of the asbestos content of a sample are somewhat empirical. Samples of typically 1 kg of material are examined by skilled analysts for suspected asbestos containing materials to be identified. Optical microscopy methods are then used for confirmation of identity, and following a specific process, the measurement of concentration both in such materials and in loose fibres is possible.
The legislation in place is primarily directed at management of asbestos contained within buildings (CAR 2012 etc.) with associated detailed requirements contained within HSE documents such as HSG 248, HSG 264 etc.
Several guidance documents have been published recently (CIRIA, AGS etc.), but no definitive guidance has been published by Government Agencies (EA/HSE) covering the subject of asbestos contamination of soils. A joint industry working group is in the process of compiling an industry code of practice that does have government backing (publication expected 2015).
Under the auspices of this group a background study of non-industrial sites is about to take place. This should allow a reasonably definitive level to be set above which site specific contamination is likely to have occured.