Developers and main contractors are used to tackling legacy asbestos found in buildings, but since 2011 the concern over asbestos found in soils has escalated.
This shouldn’t be a surprise bearing in mind that over 90% of the DOE Industry Profiles covering around 50 industry types, cite asbestos as a potential ground contaminant. You’d think that it’s the larger items, such as cement-bonded fragments, AIB fragments and small clumps of insulation found during the removal of slabs, foundations and other contaminated soil that would signal a problem. However, the site investigation team isn’t focusing on asbestos, it’s only when soil samples are checked using electron microscopy, that free fibres are discovered and the issue becomes a reality.
‘The good news is that the presence of asbestos in soil need not prevent cost-effective development of your site…’
The drive to better understand the issues has raised awareness across the industry and resulted in asbestos in soil now being found on significantly more sites than before…‘if you look then you shall find’ seems fitting for this contaminant therefore it is having a greater effect on the construction industry.
The biggest health risk from asbestos is inhaling airborne fibres, therefore the exposure to individuals needs to be assessed based on the number of fibres released from the soil into the air. During the early stage of a project it is vital that the type, condition, quantity and location of any asbestos is determined, and whether it will be disturbed or damaged at some point in the future. If asbestos is present in soil on your development site then there are three levels of risk that you need to assess:
- Whether the asbestos can be left on site or whether it needs to be disposed of
- The measures needed to protect workers and the public whilst remediation and construction are undertaken
- The measures needed to protect the end users of the site after redevelopment.
You’ll find some very useful guidance documents published by leading organisations CIRIA (Construction Industry Research & Information Association); AGS (Association of Geotechnical & Geoenvironmental Specialists); and CL:AIRE (Contaminated Land: Applications in Real Environments), namely:
- CIRIA C733 – Asbestos in soil and made ground: a guide to understanding and managing risks
- CIRIA C765 – Asbestos in soil and made ground good practice site guide
- AGS guidance for the protection of laboratory personnel
- CAR-SOILTM – Control of Asbestos Regulations 2012: Interpretation for Managing and Working with Asbestos in Soil and Construction and Demolition Materials: Industry Guidance
It’s important to understand that poor management of asbestos in soils could be a prime factor in delaying the development of your site. It could disrupt the works on site when you’re in contract and any variations will add to the costs. To successfully navigate this process you should appoint a suitably experienced remediation specialist as early as possible to investigate, identify, advise and manage the short and long-term risks. It makes sense to use an organisation that encompasses all of the regulatory, legal and construction expertise needed, so you have a robust, holistic solution that will stand up to scrutiny. Key aspects will include:
- Delineation of the asbestos in soil risk based on the site investigation data. If this isn’t sufficiently robust to provide an accurate picture of the extent of the problem, then you will need to undertake additional investigation work. Not so long ago, John F Hunt were called onto a development site to overcome problems caused by cross-contamination of spoil that had not been properly assessed. Already delayed, the project incurred unforeseen costs in the £multi-millions!
- Early engagement & planning to effectively manage the regulatory process and obtain approval of the remediation strategy. You should not underestimate the complexity and time required to obtain regulatory approval for the treatment and retention of asbestos contaminated soil on-site, failure to do so could severely delay the start of your redevelopment.
- Develop a detailed plan of work that ensures the asbestos licensing regime, site control measures and staff competencies comply with the Control of Asbestos Regulations 2012. Experience counts here and you will need to determine the most suitable option based on the site constraints and regulatory regime, including environmental permitting and licensing for any material to be re-used on site.When the way forward is clear it should be written into a detailed Plan of Work and shared with all relevant parties. Failure to follow these first three stages has led some less scrupulous developers to illegally dispose of contaminated material that has inevitably led to very large fines.
- Evidencing that the remediation objectives have been met as detailed by the validation and verification records that were agreed prior to commencing work. This might be a matter of simple record keeping or use of interactive tools like BIM (Building Information Modelling) to produce a detailed 3D model for future management of the site even after you’ve sold your interests.