Asbestos in the Soil of Construction Sites
One of the thriving industries that have faced asbestos challenges ever since the mineral became the "miracle material" in the 1930s was construction.
Even though there was an upheaval in building materials made with asbestos back then, today, those materials represent a risk when developing a construction project, especially when undertaking construction work on brownfield sites, where there's always the risk of soil being contaminated with the toxic mineral.
Asbestos building materials are a common source of soil or land contamination. The most heavily contaminated remnants are typically from historical demolition or rebuilding, which can produce hazardous waste containing every type of asbestos used in construction. These materials, which fall into two categories, underscore the breadth of the issue:
- licensed asbestos materials
- non-licensed asbestos materials
An asbestos-contaminated construction site, land, soil, or waste may contain traces of the mineral from over 3000 construction materials known to have been made with asbestos. Out of the licensed asbestos materials, the following may potentially be found:
- insulating board
- millboard
- thermal insulation
- sprayed insulation
Other products that may contaminate land, soil, or waste from the category of common non-licensed asbestos materials:
- cement
- textured coating
- vinyl floor tiles
- bitumen
- ropes and textiles
- paper, felt, and cardboard
The condition of asbestos products on the property may be identified from the remains of these products. These product pieces are crucial in asbestos tests, which gauge the extent of land or soil contamination. While it's not uncommon for asbestos to contaminate the land with large, relatively intact pieces of products, it's more typical for materials to be damaged or broken into tiny fragments.
Depending upon how long the land contained asbestos, materials on the site could be in an advanced state of degradation. The most dangerous form of land contamination is asbestos dust, composed of unbonded asbestos fibers that cover everything and float freely in the air when disturbed. Even though the larger pieces of asbestos material are visible, it is typical for asbestos-contaminated sites to have asbestos on or in the form of non-visible asbestos fiber bundles. Situations like these need adequate testing.
Higher Risks of Asbestos Contamination on Construction Sites
Asbestos health risks are well known today; thus, asbestos-contaminated land or soil hazards should be identified in every case. The health risks are more significant on brownfields because the land may host considerable amounts of damaged, fragmented asbestos materials.
Asbestos found in buildings is likely in good condition, allowing for controlled treatment and prevention of asbestos fiber release and subsequent exposure. However, asbestos in the soil or waste of construction sites is often in an advanced degraded state, with its fibrous matrix visible, making abatement difficult.
Heavy excavation machinery for land works can create a significant concentration of airborne asbestos fibers if asbestos-containing land, soil, or waste is not identified and treated correctly. This can lead to heavy exposure and subsequent asbestos-related health issues in the population of surrounding areas.
What Can You Do if You Have Asbestos-Contaminated Land, Soil, or Waste?
Each construction site with contaminated land, soil, or waste is unique, so preventive procedures must be adapted accordingly. However, if you own such property and would like to build on it, you should consider the following measures to ensure legal compliance and avoid asbestos exposure:
- Do a land survey - it will map asbestos-containing materials at the site and outline the asbestos types, how much there is of them, and where work is most likely to disturb the mineral. The survey done by a licensed asbestos inspector will include areas where you have planned excavation or groundwork and consist of trial pits to assess the depths of contamination runs if required. Brownfield or land surveys will include asbestos bulk sampling and asbestos in soil sampling and analysis, resulting in an asbestos-contaminated land risk management plan. It consists of your proposed works and details how the asbestos contamination of the land, soil, or waste will be handled to reduce the risk as low as reasonably practicable.
- Hire an asbestos contractor - it will ensure you have the expertise for regulatory compliance. Licensed asbestos contractors can provide a complete and detailed briefing for the project and enable the safe and correct handling of asbestos-contaminated land, soil, or waste. Additionally, they can adequately remove the asbestos-contaminated soil or waste, allowing your project to progress.
- Ensure continuous asbestos soil and air testing during the project - bulk sampling and soil sampling or analysis confirm where and to what extent asbestos contamination exists. Asbestos air monitoring confirms the effectiveness of all control and risk reduction measures.