practical asbestos ground investigations - ags · •asbestos type (fibrous, bound, free fibre,...

Practical Asbestos Ground Investigations

James Macfarlane, Technical Director - Asbestos

Highly Visible ACM’s

Less Visible ACM’s

Asbestos in Soils & CAR 2012

CAR 2012 extends to all ‘work’ with asbestos must be undertaken in compliance with the Control of Asbestos Regulations 2012 and L143, the associated ACoP.

This includes for soils and made ground:• Walkovers / Site Reconnaissance

• Site investigation

• Remediation

• Ground works

• Construction

• All work with asbestos requires experienced and trained staff using controls that will limit the potential for release (including subsequent exposure) and spread of asbestos fibre as far as is reasonably practicable

• CAR 2012 written specifically for asbestos in buildings and is difficult to comply with for Asbestos in soils.

• HSE: CAR2012 & Suite of HSG ACOP’s.

• CL:AIRE: ‘Definition of Waste: Development Industry Code of Practice’.

• AGS: ‘Site Investigation Asbestos Risk Assessment’.

• CIRIA: ‘Asbestos in soil and made ground: a guide to understanding and managing risks’.

• JIWG/CL:AIRE: ‘CAR-SOIL™ & Associated DST’s’.

• SCoA: ‘The Quantification of Asbestos in Soil’ (Blue Book method).

• SoBRA: Various protocols, reports, DST’s & Risk assessments.

Current Asbestos in Soils Guidance (SI related)

• HSE: ‘Analysts guidance HSG248’ – Has a section & appendix on SI procedures for Asbestos in Soils. (Unknown release date)

• JWIG/CL:AIRE): ‘Asbestos in Soil Code of Practice’ or ‘AiSCoP’. (Unknown release date)

• CIRIA: ‘Asbestos in Soils Mobile Application’. (Coming Soon)

• AGS: ‘Ground Investigations – Work with Asbestos Risk assessment for the protection of intrusive Ground Investigations and Laboratory Personnel.’ (Coming Soon)

Upcoming Guidance…..

• Aim: To bring members up-to-date on any developments to set out best practice for site walkovers, ground investigations and laboratory analysis.

• Since the 2013 AGS guidance, a host of information has been produced by the aforementioned industry bodies.

• Written to complement a the current guidance and requires a working knowledge of CAR 2012 and CAR-SOIL™.

• Does not address issues such as reuse of contaminated materials, waste management, sampling strategies or data interpretation.

AGS Update: Ground Investigations

Site Investigations

Is there a potential asbestos issue on a site?Desktop study, CSM, PRA,

• CAR2012 style management surveys are not required.• Asbestos specific GI only triggered

where a ‘reasonable expectation’ of asbestos and it may present a hazard.

• Labs only started routinely testing for asbestos in 2010-11. • Older SI’s & samples may not include

analysis for ACM

Examples of useful information/documentary evidence;o Site reconnaissance/walkover;o Previous Ground Investigation data;o Historical land use (Commercial? Industrial? Residential?);o What was being manufactured?; o Any landfill or buried waste licenses;o Ariel photographs;o Location of boiler houses (Very important – Lots of Asbestos);o Old Asbestos building surveys (Demolition/Management);o Buildings asbestos register (gained from local fire brigade?);o Historic service plans (Heating pipes – possible insulation);o The Demolition Asbestos Surveys; o UKAS Clearance certificates post removals;o H&S File / Validation reports;o Bulk and Gravimetric Analysis data;o Details of fly tipped waste/soils or imported aggregates;o Known location of made ground & demolition arising's;

What will increase the risk?

• Different level of risk for different activities

• Current site use / Surrounding receptors

• Level of disturbance

• Asbestos type (Fibrous, bound, free fibre, Amphiboles etc.)

• Surface vs Sub-surface

• Substrate type (Clay, Sand, Made Ground)

• Moisture

• Weather

• Asbestos Consultancies vs Contaminated Land Consultancies• Tendency to focus on asbestos and ignore other contaminants/risks

or visa versa.

Site Specific Risk Assessment

• Does the CSM & PRA indicate that asbestos is a likely Hazard?• Record the outcome of the assessment.

• What works are required?• Record what site works are likely to be required.

• If an asbestos hazard is present and works may create a risk, compile a Site Specific Risk Assessment for the proposed works.

• Asbestos likely present and will/may pose a risk• DS, SSRA, POW, PPE/RPE, Control/Mitigate, Competency, Monitor & Reassess

• Asbestos likely present but unlikely to pose a risk • DS, SSRA, MS, DRA + Hold points, Competency, Monitor & Reassess

• Asbestos unlikely present and no forseeable risk • DS, DRA + Hold points, Competency, , Monitor & Reassess

Notification & HSE Expectations

HSE expectations and licensing• Some members of the HSE have stated that they are not

concerned by the actual level of notification it is more the that the controls are correct.

• However huge variability across offices and between different inspectors.

• Licensing needs to correct with the correct control measures to ensure complete compliance.

• Fortunately CARSOILS™ and the JIWG have already agreed the framework with the HSE.

• CARSOILS™ Flowchart

• JIWG’s DST for Work Categories

Credit: https://www.claire.co.uk/home/news/298-cl-aire-publishes-asbestos-in-soil-guidance-car-soil

JIWG’s DST for Work Categories• If work is specifically for obtaining samples work is likely to be non-licensed!

• Control limit & SALI (0.1f/cm³ & 0.6f/cm³) NB. NOT A ‘SAFE LEVEL’

• CAR does not always apply! - <0.001% or <0.0001% = Trace?

• Clearly Identifiable & Original Form (CIOF)

• AIB vs. Fibrous Board

• Insulation vs. Fibrous Debris

Risk Assessments

Whatever the decision on licensing and notification, all ‘work with asbestos’ requires a suitable and sufficient risk assessment conducted by a competent person.

This should include:

• A description of the work to be carried out;

• Details of desktop study – If no asbestos predicted or ‘no risk’ from the present asbestos stop at this stage

• A description of any survey or laboratory analytical data;

• A description of the condition and types of asbestos;

• Details of anticipated exposures and means of controlling/recording those exposures;

• Justification why the works meets the criteria for ‘non-licensed’ works.

• Review of previous air monitoring data on similar works;

• Proposed air monitoring strategy for project;

The assessment should be a ‘Live’ document and updated if any unexpected materials are identified or the materials change from those anticipated.

Plan of works and control measures

(Asbestos specific GI’s/Sampling)

Establishing the Plan of Work

The work plan must ‘control risk and prevent harm’ whilst meeting the Ground Investigation objectives.

• Gaining a representative and homogenous sample is a skill and requires significant agitation of potentially contaminated soils.

• Samples alone provide useless information.

• Must be undertaken by suitably trained operatives with appropriate RPE, PPE and Control Measures.

• Emergency Procedures!

Training

• Asbestos Awareness Training• Soil and C&D materials specific

• Non-Licensable Work (SOILS) Training• Soil and C&D materials specific

• CAR-SOIL Training (CL:AIRE run courses)

• Surveyor - BOHS P402 • But, P409 is coming….

• Lab Analyst (UKAS) - BOHS P401, P408

• Field Analyst (UKAS) – BOHS P403 & P404

• Medicals….

Training needs analysis for the type of work being conducted.

PPE & RPE

• Disposable Respirators to standard EN149 (Type FFP3);

• Disposable Respirators to standard EN405 with P3 filter;

• Half Mask; Respirators to standard EN140 with P3 filter;

• Full face mask powered respirator to standard EN12942;

• Type 5 or 6 (BS EN ISO 13982-1+A1) disposable coverall with hood;

• Safety gloves & Nitrile gloves (disposable);

• Safety boots/wellington (without laces).

• High Visibility? (dedicated to asbestos area);

• Disposable underwear?

Control Measures

• Segregate work area ‘so far as is reasonably practicable’ and erect suitable warning.

• Single point of egress through decontamination facility.• Primary decontamination usually sufficient for Gi purposes.

• Full decontamination facilities may require additional training.

• Limit staff to essential personnel only.

• Suitable dust suppression to maintain high moisture levels.

• Minimise double handling.

• Remain up wind of any disturbance where practical.

• Consider neighbours and other site staff.

• Leave the site safe…

Delineation Methods, Sampling, Logging

• Trial pitting/trenching best for identification of asbestos.

• The descriptions of any Made Ground must follow the British Standard BS 5930 and include asbestos descriptors:

• All samples of made ground suspected to contain asbestos must be double-bagged and all bags marked “suspected asbestos”.

• Laboratories/Couriers must be warned before dispatch of samples of suspected asbestos containing samples.

Leaving the site safe

• Ground protection measures;

• Decontamination of all plant/equipment with the potential for contamination;

• Any surface ACM post SI must be left in a satisfactory condition awaiting remediation;

• Hand picking

• Clean capping

• Barrier layer

Air monitoring and Analysis

• Air monitoring can be valuable line of evidence to show control measures are effective provided it used in the right conditions:

• Boundary monitoring

• Reassurance monitoring

• Personal monitoring

• Inside adjacent buildings/site offices

• In the lab drying, sieving, crushing material poses the greatest risk.

• Preliminary assessment of sample

• HEPA fume cabinets

• Waste disposal provisions

QUESTIONS…..