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2012 September AGS 2012 Interim Guidance on Site Investigation Asbestos Risk Assessment Ver 2-2

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2012 September AGS 2012 Interim Guidance on Site Investigation Asbestos Risk Assessment Ver 2-2 Powered By Docstoc
					Site Investigation Asbestos Risk Assessment
                     For the protection of
   Site Investigation and Geotechnical Laboratory Personnel


                    AGS Interim Guidance




                      September 2012


                           Ver 2.2
    Site Investigation Asbestos Risk Assessment
    for the protection of Site Investigation and Geotechnical Laboratory personnel
     AGS Interim Guidance September 2012                                                    Page 2 of 23


                                                 Contents

   Site Investigation Asbestos Risk Assessment                                                        1

Contents                                                                                              2

Foreword                                                                                              4

1. Site Investigation Planning                                                                        5

   1.1     Background                                                                                 5

   1.2     Site Investigation Asbestos Risk Assessment                                                5

2. Basic Principles                                                                                   7

   2.1     Human Health                                                                               7

   2.2     Safe Exposure Limit                                                                        7

   2.3     Moisture Content and Drying                                                                7

   2.4     Asbestos Cement and Free Fibres                                                            7

   2.5     Personal Protective Equipment (PPE) and Respiratory Protective Equipment (RPE)             7

   2.6     Disposal of Asbestos                                                                       8

3. Site Investigation Asbestos Risk Assessment                                                        9

   3.1     Risk Assessment Considerations                                                             9

   3.2     Initial Risk Assessment                                                                    9

   3.2.1   Pre-Visit Risk Assessment                                                                  9

   3.2.1.1 Industry                                                                                   9

   3.2.1.2 Made Ground (fill)                                                                        10

   3.2.1.3 Landfills                                                                                 10

   3.2.1.4 Demolition of Structures                                                                  10

   3.2.1.5 Construction Platforms                                                                    10

   3.2.1.6 Fly-Tipping                                                                               10

   3.2.2   Initial Site Visit                                                                        10

   3.2.3   Review of Initial Risk Assessment                                                         11

   3.3     Fieldwork Risk Assessment                                                                 11

   3.4     Dynamic Risk Assessment                                                                   11

4. Fieldwork                                                                                         13

   4.1     Fieldwork Risk Assessment                                                                 13

   4.2     Training                                                                                  13
    Site Investigation Asbestos Risk Assessment
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     AGS Interim Guidance September 2012                                    Page 3 of 23

   4.3    Care of Spoil/ Arisings/ Exposed Soil                                      13

   4.4    Unexpected Asbestos                                                        13

   4.5    Soil Sampling                                                              14

5. Soil Laboratory Testing                                                           15

   5.1    Laboratory Asbestos Management Plan                                        15

   5.2    Training                                                                   15

   5.3    Sample Handling and Screening                                              15

   5.4    Laboratory Health and Safety Requirements                                  15

   5.5    Waste Disposal                                                             16

6. . Appendices                                                                      17

6.1 SITE INVESTIGATION PROCEDURE                                                     18

6.2 AGS SIARA FORM A (Site Usage)                                                    19

6.3 AGS SIARA FORM B (Site Features)                                                 20

6.4 Fieldwork Procedure                                                              21

6.5 Dynamic Review                                                                   22

6.6 Geotechnical Laboratory Procedure                                                23
     Site Investigation Asbestos Risk Assessment
     for the protection of Site Investigation and Geotechnical Laboratory personnel
      AGS Interim Guidance September 2012                                                                  Page 4 of 23


Foreword

Site investigation is rarely carried out with the specific purpose of assessing the presence of asbestos on or beneath
the surface of a site.

Investigations to BS5930 are not directed at the potential contamination of a site and the exploration of the ground
may be directed entirely at obtaining geotechnical information or investigating the form of buried structures or
geological features.

Where land contamination is suspected CLR11 indicates that initial/preliminary assessments should be carried out as
the first step in consideration of the risks associated with potentially contaminated land. Detailed guidance for
preliminary investigations is set out in BS10175.

In all circumstances where work of any nature is to be undertaken at a site, regardless of the purpose, there is a need
to assess the potential for human health exposure risks to occur to those who may be involved directly or indirectly
with the investigation process. The principal legal drivers for this are the Control of Asbestos Regulations 2012
(CAR2012).

There is existing HSE guidance that can be readily applied to the presence of asbestos in buildings and asbestos that
is lying on the surface of the ground. In the absence of specific government advice in regard to asbestos contained in
soils, this guidance is issued to AGS members so that they may be aware of their responsibilities and to offer a
practical means of discharging their duties pending the publication of new guidance from HSE.




          This soil evidently contains crushed demolition rubble. Is it safe to take dig out a bulk sample and
          carry out a sieve analysis to see if it complies with a 6F2 grading?
      Site Investigation Asbestos Risk Assessment
      for the protection of Site Investigation and Geotechnical Laboratory personnel
          AGS Interim Guidance September 2012                                                                          Page 5 of 23


1. Site Investigation Planning

1.1        Background
All employers have a duty to provide a safe working environment for their employees and this requires them to assess
and manage any potential asbestos risk. For the site investigation industry there is an enhanced risk of encountering
the unexpected. The business of ground investigation is inherently one of discovery.

The Health & Safety Executive will expect employers to be aware of their responsibilities, to carry out a process of risk
assessment prior to visiting any site, to organise appropriate working methods in the light of that assessment and to
have a procedural system in place for their employees to react to and deal safely with any unexpected asbestos that
may be encountered.

The key issues to be assessed are as follows:

      •     Is there a risk of asbestos being present at the site?
      •     Is there a risk of any release of asbestos fibres into the air?
      •     Is there a risk of any such release exceeding the Workplace Exposure Limit (WEL)? (see Section 2.2)

If the answer to the last question is “maybe”, then the work is almost certainly Notifiable under CAR2012, if the answer
is “yes” then the work is almost certainly Licensable under CAR2012. For an explanation of these terms, the reader
must consult HSE guidance.

1.2        Site Investigation Asbestos Risk Assessment
A suggested process for completing a site investigation asbestos risk assessment is described in Section 3.

The very first assessment must be completed before anyone even visits the site. This assessment must then be
refined following the initial site visit to inform the planning of any subsequent fieldwork activities.

Site-specific method statements should be produced for every type of planned fieldwork activity using risk
assessments specific to each.
                                                                            1
Where the site being investigated is a non-domestic premises, the dutyholder has historically had a statutory legal
responsibility to have an asbestos assessment carried out and where that assessment has positively identified
asbestos to be present to develop a written Asbestos Management Plan and make those who plan to undertake work
on the premises aware of it. (Note: It has been clarified that the CAR2012 regulations apply also to the land included
in the premises and not just to any buildings or structures present. However, it is the experience of AGS members that
asbestos assessments have in the past seldom been extended to other than building surveys.)




1
  "the dutyholder" means—
(a) every person who has, by virtue of a contract or tenancy, an obligation of any extent in relation to the maintenance or repair of
non-domestic premises or any means of access thereto or egress therefrom; or
(b) in relation to any part of non-domestic premises where there is no such contract or tenancy, every person who has, to any extent,
control of that part of those non-domestic premises or any means of access thereto or egress therefrom,
    Site Investigation Asbestos Risk Assessment
     for the protection of Site Investigation and Geotechnical Laboratory personnel
      AGS Interim Guidance September 2012                                                                    Page 6 of 23

Nevertheless, if at any stage and for any reason the site investigation assessment identifies that there may be a
potentially unacceptable risk of asbestos exposure to employees or the general public, or if there is significant doubt,
the investigation plans and any on-going works must be suspended pending a specific Asbestos Survey and risk
assessment undertaken in accordance with the 2012 Control of Asbestos Regulations (CAR 2012) regulations. This
will require the services of a trained asbestos specialist. It is re-iterated that in the case of a non-domestic premises,
the owner (duty holder) has a legal duty to complete this assessment. The site investigation can then proceed only
under the terms of the resulting Asbestos Management Plan.




         Here a flat sheet of asbestos cement is attached to the demolition rubble. It was used as
         shuttering or wall cladding and now has ended up in demolition rubble. Such materials can get re-
         used several times over successive developments

          Is it safe to carry out plate bearing tests on a piling mat that includes this sort of material?
      Site Investigation Asbestos Risk Assessment
      for the protection of Site Investigation and Geotechnical Laboratory personnel
          AGS Interim Guidance September 2012                                                              Page 7 of 23


2. Basic Principles

2.1        Human Health
The specific risks from asbestos relate to the potential release of respirable fibres into the atmosphere when
disturbed. Even low levels of fibre release can present a risk to health. The fibres or dust once exposed may be
released into the atmosphere by the wind, by construction activities or by the movement of vehicles or construction
plant.

2.2        Safe Exposure Limit
In the UK an unacceptable risk to human health from the inhalation of asbestos fibres is reported by the Health and
Safety Executive (HSE) as exceedance of the Workplace Exposure Limit (WEL) of 0.01 fibres/ml airborne asbestos
for a continuous average over a four hour period.

No other specific guideline values for air, water or soil have been published by the UK government, although it should
be noted that the Health Protection Agency (HPA) have suggested that a ‘safe’ level of exposure would be much
lower than this.

It should be particularly noted that the ≥0.1% asbestos by weight definition used for the classification of Hazardous
Waste CANNOT be used for human health risk assessment purposes. Asbestos concentrations 100 times smaller
than this have been found capable of giving rise to exceedances of the WEL.

2.3        Moisture Content and Drying
Studies have demonstrated that the addition of 10% of water to soil decreases the risk of the potential release of
asbestos fibres to air by a factor between 2 and 10. Most soil is damp when in-situ and poses little risk of fibre
release, but once excavated or exposed it may be dry very quickly. Locations commonly identified on sites having this
potential are excavations or intrusive hole locations, spoil, areas where any hard surfacing is removed, vehicle routes
passing between soft ground and hard standing, open skips and mudded/soiled boots and clothing.

If the site presents dry, well-drained by coarse-grained granular soil or fill at the surface, the fibres tend to become
airborne more readily. The presence of any airborne dust is a sign of potential immediate hazard.

2.4        Asbestos Cement and Free Fibres
The risk of fibre released into the air is increased if the asbestos is present in the form of friable materials or loose
fibres. Laboratory studies have shown that dangerous concentrations of respirable fibres may be released from loose
dry soil with asbestos concentrations of as low as 0.001% by weight.

Release of fibres tends to be reduced when the asbestos is present in the form of intact manufactured articles such as
asbestos-cement boards, sheets and pipes.

2.5        Personal Protective Equipment (PPE) and Respiratory Protective Equipment (RPE)
Standard dust masks such as are normally available at DIY stores do not provide protection against respirable
asbestos fibres. The HSE specify the following Respirators for specific protection against asbestos inhalation:

      •     Disposable Respirators to standard EN149 (Type FFP3) or EN1827 (Type FMP3)
      •     Half Mask Respirators to standard EN140 with P3 filter
      •     Semi Disposable Respirators to standard EN405 with P3 filter
.
      Site Investigation Asbestos Risk Assessment
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      AGS Interim Guidance September 2012                                                                    Page 8 of 23

The HSE also provide specific guidance on suitable clothing and footwear to be worn where there is a risk of potential
                   2                                                                                    3
asbestos exposure . Guidance is also provided on procedures for cleaning and disposal of this PPE .



2.6    Disposal of Asbestos
Guidance is provided by the HSE on the disposal of asbestos4.




           You will notice the white fibrous material but did you notice the same lagging mixed with clay at
           bottom right of the picture? Although this material appears white in colour it is in fact Amosite
           (Brown Asbestos). What would you do if you came across this in a trial pit?




2
  HSE Information Sheet EM6 Personal Protective Equipment (PPE) Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
3
  HSE Information Sheet EM8 Personal Decontamination. Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
4
  HSE Information Sheet EM9 Disposal of Asbestos Waste. Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
      Site Investigation Asbestos Risk Assessment
      for the protection of Site Investigation and Geotechnical Laboratory personnel
          AGS Interim Guidance September 2012                                                             Page 9 of 23


3. Site Investigation Asbestos Risk Assessment

3.1        Risk Assessment Considerations

In the absence of any certified testing, only a qualitative risk assessment can be completed. Nevertheless, a semi-
quantitative judgement has ultimately to be made using this assessment as to whether there is a risk of the asbestos
WEL being exceeded. Where there is any doubt, this judgement may be assisted by the services of an asbestos
specialist.

Each site investigation asbestos risk assessment should consider:

      •         Whether asbestos may be present at the ground surface
      •         The nature of the ground which may contain asbestos
      •         The types of asbestos likely to be present
      •         The form in which the asbestos is likely to be present, eg individual fibres, cement bound asbestos,
                loose lagging material, distributed over the site or in a concentrated mass
      •         Exposure pathways
      •         The personnel and/or public that could be at risk both on and off-site

A flow-chart setting out a procedure is appended at 6.1 of this report.


3.2        Initial Risk Assessment

Planning a site investigation must commence with a desk top assessment, using the usual desk study sources of
information, including “birdseye” and “streetview” photography, to help decide what level of risk is associated with the
site by virtue of its current use and previous historical uses and whether fill containing asbestos may have been
imported.

Any existing asbestos-related assessments or asbestos management documentation for the site should be taken into
account at this stage, together with checking building plans, property use and interviewing property owners, occupiers
or locals who may have relevant historical knowledge.


3.2.1       Pre-Visit Risk Assessment

In order to demonstrate that a pre-visit asbestos risk assessment has been carried out the AGS SIARA Form A
(appended at 6.2) can be completed on the basis of site usage for the benefit of any persons intending to visit the site
during the investigation planning stage.


3.2.1.1       Industry

Examples of high risk previous site usage would be the manufacture of brake pads, pipe lagging, asbestos sheeting,
asbestos pipes, asbestos blankets, ceiling tiles, wall panels, cladding, etc. Other high risk sites could be breakers
yards, naval and other military installations, ship builders and heavy engineering works, depots, workshops, boiler
houses, power stations, former railway premises and scrap yards. Land that may have received fill from any of the
above industries should also be assigned a high risk.
     Site Investigation Asbestos Risk Assessment
     for the protection of Site Investigation and Geotechnical Laboratory personnel
     AGS Interim Guidance September 2012                                                                     Page 10 of 23

3.2.1.2    Made Ground (fill)

Historical fills are notoriously prone to containing asbestos. In many cases demolition at the sites where the fill
materials originated may have been carried out with no regard to the risks associated with asbestos. Other possible
situations where asbestos could be present would be infill to below-ground structures such as basements, sumps, gas
holder bases, tank chambers, shafts, tunnels, culverts, shelters, etc. Also an excavation may have been formed for
the deliberate purpose of disposing of asbestos, using the excavated material to then cover the asbestos. This
practice was relatively common on some agricultural premises.


3.2.1.3    Landfills

For old landfills, particularly those filled prior to 1974 when waste management licensing was first introduced,
asbestos disposal took place together with and often mixed with other wastes. Unless the landfill is very recent and
the licence specifically excludes asbestos then it should be assumed that a landfill may potentially contain asbestos.
For older landfills post 1974, licences were initially often poorly ‘policed’ and therefore materials may have been
placed in a landfill that was not permitted by the licence, sometimes by fly-tipping.


3.2.1.4    Demolition of Structures

Poor control of demolition at the sites has often been a cause of asbestos contamination of the ground. In some cases
this has resulted in asbestos being strewn across the site and tracked into the ground by plant. Unfortunately there
are cases where this has occurred in respect of quite recent demolition. This does not mean to imply that all
demolition has been poorly controlled but in the absence of specific evidence it is often difficult to know which ones
have and which ones have not been undertaken correctly.


3.2.1.5    Construction Platforms

There have been cases where a site was shown to have been free of asbestos by site investigation but where
asbestos was subsequently introduced to the site contained in the materials used to form a construction platform, eg
piling mats formed of recycled crushed aggregate.


3.2.1.6    Fly-Tipping

A site may have no history of asbestos having been on the site and may not have received any fill but asbestos could
still be present as a result of unregulated fly-tipping. Even now, fly-tippers are flaunting the law and it could be argued
that because of the higher cost of disposing of asbestos compared to many other wastes, there is more incentive to
fly-tip asbestos containing material than many other types of waste.


3.2.2     Initial Site Visit

The purpose of any initial site visit made during the investigation planning stage is to usually assist with the scoping of
the investigation. This initial site visit is not expected to be a detailed survey, but should be used to further inform the
Site Investigation Asbestos Risk Assessment using AGS SIARA Form B (appended at 6.3). The prospective site
visitor should be briefed on the basis of AGS SIARA Form A, and have

1.        An awareness of asbestos.

2.        An understanding of basic precautions to avoid health exposure
      Site Investigation Asbestos Risk Assessment
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      AGS Interim Guidance September 2012                                                                      Page 11 of 23

3.         Appropriate PPE/RPE

4.         An ability to complete the AGS SIARA Form B

(Note: An initial site visit may sometimes be purely concerned with the accessibility of different areas of the site and
practical constraints to the selection of various site investigation equipment such as drilling rigs, mechanical plant and
vehicles. It should be born in mind that such a visit may need to be undertaken by a person who is not sufficiently
trained to be in a position to complete Item 4 above.)


3.2.3      Review of Initial Risk Assessment

In order to demonstrate that a pre-investigation asbestos risk assessment has been carried out, the AGS SIARA Form
B can be completed for the benefit of any persons intending to subsequently plan and assess the site investigation
methodology and specific activity-related risk assessments and should therefore be kept in an appropriate location
such as the project file. The essential objective at this stage is to identify any additional visible features of the site that
give rise to any increased risk of asbestos exposure. While the investigator may note the presence of any suspected
ACM that is observed, it is the presence of non-observable fibres that presents the greatest risk.                 Hence the
investigator is particularly looking for indirect evidence of the possible site presence of the remains of the following:

      •    Fireproofing (eg. boilers, furnaces, incinerators).
      •    Thermal insulation (eg. below-ground heating ducts)
      •    Fibre-cement moulded products (eg.roofing sheets, rainwater goods, cladding, pipes and tanks.
      •    Thermal and sound insulation (eg discarded building materials, recycled demolition materials)


If the review concludes for any reason that there may be a potentially unacceptable risk of asbestos exposure, or if
there is doubt, the investigation plans must be suspended pending a specific Asbestos Survey and risk assessment
being undertaken. This will require the services of a trained specialist. It is re-iterated that, in the case of a non-
domestic premises, the dutyholder has a legal duty to complete this assessment. The site investigation can then
proceed, but only under the terms of the resulting Asbestos Management Plan.



3.3       Fieldwork Risk Assessment

The process of completing a site investigation fieldwork risk assessment is described in Section 4.


3.4       Dynamic Risk Assessment

A system of Dynamic Risk Assessment is required so that if at any stage of an investigation the conditions are not as
expected and/or an unexpected situation arises during the investigative work, the fieldwork risk assessment is
immediately reviewed.

A suggested possible flow chart for Dynamic Risk Assessment is appended at 6.5. The steps are as follows;

Step 1. Evaluate the Situation, Tasks and Persons at Risk

      •        Is there an existing dutyholder?
      •        What information is available?
      •        What tasks need to be carried out?
      •        What hazards are associated with these tasks in this situation?
    Site Investigation Asbestos Risk Assessment
     for the protection of Site Investigation and Geotechnical Laboratory personnel
    AGS Interim Guidance September 2012                                                                    Page 12 of 23

    •        What risks are associated with carrying out these tasks – to site investigation staff or the public?
    •        What resources are available e.g. experienced personnel, specialist equipment, etc?

Step 2. Select Operational Procedures

    •        Consider the various options and select the most appropriate for the situation.
    •        The starting point must be consideration of any procedures agreed prior to the investigation and any
             associated training previously given to the staff involved.
    •        Ensure that personnel are competent to carry out the tasks under the circumstances encountered.



Step 3. Assess the Chosen Operational Procedure

    •        Assess the chosen procedure – are the risks acceptable?

If YES, proceed with the task after ensuring that:

    •        The objectives and tasks are fully understood by all persons at potential risk of exposure.
    •        The responsibilities have been clearly allocated and outlined.
    •        Safety measures and procedures are documented, understood and implemented, with continuing
             dynamic assessment.

If NO, continue as below.

Step 4. Introduce Additional Controls

Eliminate, or reduce any remaining risks to an acceptable level, if possible by additional control measures, such as:

    •        The use of additional PPE and RPE.
    •        Use of specialist equipment.
    •        Assistance from other bodies – Specialist asbestos advisor
    •        Nomination of a member of the site investigation team to act as the co-ordinator in respect of any issues
             associated with asbestos.

Step 5. Re-assess Operational Procedures and Additional Control Measures

If any risks remain, are these acceptable?

    •        If the risks are acceptable, proceed with the task
    •        If the risks are unacceptable, do not proceed with the task, but consider alternatives.
      Site Investigation Asbestos Risk Assessment
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      AGS Interim Guidance September 2012                                                                Page 13 of 23


4. Fieldwork

4.1        Fieldwork Risk Assessment

Each fieldwork activity should be planned and undertaken using an activity-specific Risk Assessment and Method
Statement (RAMS) and taking into account the initial or proceeding site investigation risk assessment. For example, it
should be recognised that there is an increased risk of releasing fibres from trial pitting.


4.2        Training

All field personnel considered likely to have potential contact with ACMs must receive specific asbestos awareness
training. This will need to be updated as appropriate to the potential risk identified.


4.3        Care of Spoil/ Arisings/ Exposed Soil

The act of trial pitting and drilling can result in the breaking up of ACMs within the ground. By using the dynamic risk
assessment approach described earlier it is possible to constantly review the ground conditions being revealed by the
investigation and to react to a changing situation.

The asbestos exposure risk depends not just upon the type of soil and material revealed, but also upon the weather
conditions.

Made ground, particularly that containing any signs of foreign matter such as bricks or other building debris present a
very different situation to the exposure of natural soils.

A particular watch needs to be kept for potential drying of any exposed made ground soil arisings. In the absence of
water to damp down arisings and exposed soil that may be drying, consideration may be given to sheeting the soil to
prevent drying.

Normally, all exploratory excavations are backfilled immediately upon completion, returning each type of soil in
sequence back to the original position and not leaving anything but the reinstated site surface upon completion.
Where re-instatement of turves or hard surfacing is not undertaken, it may be preferable to use natural soils as the
topmost cover layer at the ground surface where a possibility of asbestos has been identified in the made ground.

In no circumstances should arisings of soil that are suspected to contain asbestos be left at the ground surface, where
they could potentially give rise to any air-borne fibre release.


4.4        Unexpected Asbestos

CAR 2012 requires that in the event of an accident, incident or emergency an employer must, amongst other things,
take immediate steps to:

      1.     Mitigate the effects of the event
      2.     Restore the situation to normal, and
      3.     Inform any person who may be affected
      Site Investigation Asbestos Risk Assessment
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      AGS Interim Guidance September 2012                                                                        Page 14 of 23

The following field procedure is suggested if something suspected to be asbestos is encountered. The HSE have
                                                                                                             5
provided guidance as to what to do upon discovery of suspected asbestos source material in buildings . If in doubt get
competent help.

      •    Don’t panic – asbestos is only dangerous when disturbed and fibres are released and inhaled. If it is safely
           managed and contained it does not present a health hazard. The most commonly identifiable material found
           on or in the ground is fragmented asbestos cement sheeting. Bonded asbestos is not hazardous as long as it
           is not significantly disturbed, drilled or broken.
      •    Don RPE and clear the area of personnel without RPE.
      •    Without disturbing it further, try to assess what condition the suspected asbestos is in, whether it is fibrous
           and loose or an ACM. If possible take a photograph.
      •    Assess if the condition or the location means that the material is likely to be disturbed.
      •    Dampen the suspected material where possible.           The HSE have provided guidance on the wetting of
                                 6
           asbestos materials.
      •    If the material is an isolated fragment of ACM then you may sample it as part of the soil sampling process
           provided that it is safe to do so. Do not break up the material to sample it. Place the soil sample in a secure
           container and, in addition to normal labelling, label the sample as suspected of containing asbestos material.
           Place the sample container in a sealed sample bag and label this again. This is for the benefit of those
           involved in transport, storage or laboratory testing. Failure to warn laboratories of the potential for asbestos in
           samples is a major cause of exposure.
      •    Do not remove or disturb any asbestos other than for sampling unless absolutely unnecessarily. Always
           leave it where it was found because disturbing it may lead to the release of fibres.
      •    Review the situation against the fieldwork risk assessment to decide whether and how the intended fieldwork
           activity can be continued safely. If in doubt do not proceed until a further assessment by a specialist has
           been made.
      •    If the material is visibly fibrous and loose or there is a significant amount of suspect material, ie. not isolated
           fragments, then work should stop immediately as there is a potential risk of spreading the asbestos and of a
           wider exposure. In this case follow the HSE guidance referred to above, which refers to isolating the
           exposure and decontamination protocols.



4.5       Soil Sampling

This guidance is intended to assist the course of normal site investigation processes and does not apply to the
dedicated asbestos investigation or asbestos survey of a site which should only be undertaken by appropriately
qualified specialists. Such work requires the services of specially trained personnel at all levels, equipped and
experienced in the identification and sampling of asbestos.

A stated above if a soil sample is taken, and on examination it is suspected to contain asbestos, place the soil sample
in a secure container and, in addition to normal labelling, label the sample as suspected of containing asbestos
material. Place the sample container in a sealed sample bag and label this again. The procedure outlined in the
previous section regarding unexpected asbestos should be followed.




5
  HSE Information Sheet EM1 What to What to do if you uncover or damage materials that may contain asbestos. Non-Licensed
Tasks. Asbestos Essentials Task Manual (2001).
6
  HSE Information Sheet EM5 Wetting Asbestos Materials. Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
       Site Investigation Asbestos Risk Assessment
       for the protection of Site Investigation and Geotechnical Laboratory personnel
       AGS Interim Guidance September 2012                                                                     Page 15 of 23


5. Soil Laboratory Testing

5.1       Laboratory Asbestos Management Plan

All laboratories must have procedures in place to protect their staff from possible exposure to asbestos. It is the
experience of AGS members that the controls present in analytical chemical laboratories have not been present in
some geotechnical laboratories. Whereas the awareness of asbestos risk may be heightened in a laboratory that is
equipped for the identification of asbestos, this may not be the case in a geotechnical soils laboratory.

However, the deliberate drying, crushing or sieving of soils in a laboratory must be recognised as possibly the most
dangerous of all activities associated with site investigation where there is a possible presence of asbestos, for there
is a high probability of respirable asbestos fibres being released in close proximity to staff.

The laboratory design and working procedures must either be wholly protective based upon an assumption of
asbestos being present in the samples, or have a secure method of only releasing samples into a conventional soils
laboratory environment once these have been assessed as not being at risk of containing asbestos.                A flowchart
procedure is appended at section 6.6 of this report.


5.2       Training

All laboratory staff likely to have potential contact with soil samples containing asbestos must receive specific
asbestos awareness training.


5.3       Sample Handling and Screening

Most geotechnical laboratories do not have the capability to identify whether a sample contains asbestos. If this is the
case, it will be necessary to store all suspect samples in a safe quarantine area and to send suspected asbestos
samples or sub-samples to an analytical laboratory for screening.

Following screening results the samples or sub-samples may be assessed and deemed to be clear of asbestos and
the samples and the materials can be moved away from the quarantine area and geotechnical testing can proceed.


5.4       Laboratory Health and Safety Requirements

In the absence of a screening system, or a laboratory environment that is specially equipped for handling asbestos
dusts, the laboratory must be regarded as potentially contaminated by asbestos fibres.                It is essential that all
                                                                                                  7
laboratory personnel are equipped with and wear the appropriate PPE and RPE                           and that appropriate
                                             8
decontamination procedures are followed .

The HSE also provide specific guidance on suitable clothing and footwear to be worn where there is a risk of potential
asbestos exposure. Guidance is also provided on procedures for cleaning and disposal of this PPE.

Conventional laboratory cleaning and dust suppression procedures cannot be applied where there is an asbestos risk.
The filters used in conventional laboratory dust extraction systems and vacuum cleaners do not work with asbestos
fibres.


7
    HSE Information Sheet EM6 Personal Protective Equipment (PPE) Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
8
    HSE Information Sheet EM8 Personal Decontamination. Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
      Site Investigation Asbestos Risk Assessment
      for the protection of Site Investigation and Geotechnical Laboratory personnel
      AGS Interim Guidance September 2012                                                                    Page 16 of 23

Where geotechnical testing is to be undertaken and asbestos fibres have been identified the testing should be carried
out in a dedicated laboratory environment where the risks from inhalation of airborne asbestos fibres can be safely
controlled (e.g in a fume cupboard equipped with a suitably filtered decontamination unit ).
                                                                                                    9
The HSE have provided guidance for using damp rags to clean surfaces of minor asbestos contamination .




5.5     Waste Disposal

PPE and clothing and soil samples containing only low levels of asbestos contamination can be disposed of in a
standard fashion.

Asbestos is a hazardous waste when at quantities greater than 0.1% by weight.
                                                                10
Guidance is provided by the HSE on the disposal of asbestos .




          This is a close-up of asbestos insulation board in soil. It can also be coloured or dyed and painted
          or sandwiched in other materials such as paper, wood, cork and metal also with bituminous
          materials and coverings. Will it be ok to sample the soil as long as you leave the big piece alone?
          Should you put on a dusk mask of some sort?




9
  HSE Information Sheet EM7 Using damp rags to clean surfaces of minor asbestos contamination. Non-Licensed Tasks. Asbestos
Essentials Task Manual (2001).
10
   HSE Information Sheet EM9 Disposal of Asbestos Waste. Non-Licensed Tasks. Asbestos Essentials Task Manual (2001).
Site Investigation Asbestos Risk Assessment
for the protection of Site Investigation and Geotechnical Laboratory personnel
AGS Interim Guidance September 2012                                               Page 17 of 23


                                     6. APPENDICES




      What should you write on the AGS SIARA Form B?

      If it is windy should you put on PPE/RPE before walking across this site?

      If it is raining should you put on PPE/RPE?
Site Investigation Asbestos Risk Assessment
for the protection of Site Investigation and Geotechnical Laboratory personnel
AGS Interim Guidance September 2012                                                      Page 18 of 23


              6.1 SITE INVESTIGATION PROCEDURE


     START



     Desk top
      study

                                 This assessment can be recorded using
                                 SIARA Form A and Form B. Form A is
                                 intended to be completed following the desk
                                 study, to inform the first visit to the site. Form
                                 B is intended to be completed during the first
    Is there a                   visit to the site. Both forms are required to
foreseeable risk                 enable the planning of any Fieldwork.

  of asbestos                                                                          Proceed
being present on                                      NO                              as Normal
       site?
                                  Fibre release depends on
               YES                •    Type of material (insulation, lagging other
                                       loose materials.. higher potential, board
                                       cement)
                                  •    Condition eg damaged/well broken up
    Is there a                    •    Wet/damp or dry
                                  •    Buried or not
foreseeable risk                                                                      Proceed with
of air-borne fibre                                                                     Due Care
     release?                                            NO



              YES
                                  Investigation is Notifiable under CAR2012
                                  unless the risk assessment clearly indicates
                                  that the exposure of any employee to asbestos
    Is there a                    is not liable to exceed the Control Limit.
foreseeable risk                                                                      Proceed only
 of Control Limit                                                                      with Expert
  exceedance?                                              NO                          Guidance


              YES

     Do Not
     Proceed
     Site Investigation Asbestos Risk Assessment
     for the protection of Site Investigation and Geotechnical Laboratory personnel
     AGS Interim Guidance September 2012                                                   Page 19 of 23


                    6.2 AGS SIARA FORM A (Site Usage)


 Ref:                 Site:                                      Date:          Completed by:        .

                                                                                       Assessed
        Period                             SITE USAGE
                                                                                         Risk
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Examples:
Low Risk:               Greenfield sites.
Moderate Risk:          Sites developed, altered or refurbished in 1930s-1980s. Landfills.
                        Made Ground (Fill). Allotments.
High Risk:              All buildings and refurbishments 1960s-1970s. Asbestos product works..
    Site Investigation Asbestos Risk Assessment
    for the protection of Site Investigation and Geotechnical Laboratory personnel
    AGS Interim Guidance September 2012                                                   Page 20 of 23


                  6.3 AGS SIARA FORM B (Site Features)


 Ref:                Site:                                      Date:          Completed by:        .
   Site Feature                                                                       Assessed
  (Reference on                           Description
       Plan)                                                                            Risk
        A
        B
        C
        D
        E
        F
        G
        H
        I
        J
        K
        L
       M
        N
        O
        P
        Q
Examples:
Low Risk:              Undisturbed Hard Cover.
Moderate Risk::        Crushed Recycled Aggregate. Building and Demolition waste. Backfilled
                       basements. Bare soil with potential to generate dust in dry condition..
High Risk:             Visible asbestos
                       Dust. (especially demolition and where nearby asbestos working/storage)
Site Investigation Asbestos Risk Assessment
for the protection of Site Investigation and Geotechnical Laboratory personnel
AGS Interim Guidance September 2012                                    Page 21 of 23


                           6.4 Fieldwork Procedure

                                      Select Fieldwork
                                          Activity


                                       Prepare
                                  Fieldwork RAMS



                                   Do you have a
                                 Fieldwork RAMS                NO
                                  that adequately
                                     addresses
                                     asbestos?

                                              YES
                                  Proceed with
                                Fieldwork Activity



                                  Unexpected             NO
                                Asbestos Found?


                                              YES

                                 Dynamic Review




         YES                    Is it acceptable to            NO
                                   proceed with
                                      activity?
      Site Investigation Asbestos Risk Assessment
      for the protection of Site Investigation and Geotechnical Laboratory personnel
     AGS Interim Guidance September 2012                                     Page 22 of 23


                                   6.5 Dynamic Review


                                   Evaluate the situation,
                                 tasks and persons at risk




Consider viable                              Select
 alternatives                              operational
                                           procedure




                                                    Assess the chosen
                                                   operational procedure


                           Proceed with
                              tasks

                                                         Are the risks
                                                         acceptable?
                                YES



                                                         NO



Do not proceed           NO             Can additional            YES       Re-assess
  with tasks                           control measures                     systems of
                                        be introduced?                       operation
  Site Investigation Asbestos Risk Assessment
  for the protection of Site Investigation and Geotechnical Laboratory personnel
 AGS Interim Guidance September 2012                                          Page 23 of 23


               6.6 Geotechnical Laboratory Procedure


              Sample receipt




           Is lab specially
             equipped to                     NO              Quarantine
            safely handle                                     Sample
              asbestos?



           YES
                                 Is sample labelled                    YES
                                    as potentially
                                     containing
                                     asbestos?

                                                  NO

                                                                      Is there a   YES
                        Request AGS                                    definite
                      SIARA Form A + B                              asbestos risk?

                                                                NO



                                       YES
                                                   Is the sample
                                                    natural soil?

 Proceed with                                          NO
  geotechnical
                        CLEAR            Sub-sample wearing PPE           Asbestos
  testing using
                                          and send to analyst for
correct PPE and
                                                screening                 Detected
decontamination
   procedures

				
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