Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:1850:p66
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 1850 (pt 66/117)
Character Range: 531473–534712

site investigation
As for all site assessments, the PSI should include a desktop study (including assessment of site history) and a site inspection. This should be carried out by a qualified and experienced assessor/competent person.

As noted in WA DoH (2009a), asbestos contamination needs to be identified early in the assessment process and properly handled to ensure that disturbance does not result in dissemination of asbestos contamination and hence delays and additional investigation effort.

    11.2.1      Site history investigation
The site history investigation should follow the process outlined in Section 3 and include the following asbestos-specific considerations:
    * an evaluation of information, including inspection of aerial photographs, to determine the likely presence of asbestos associated with
               any remaining or demolished structures and buildings (including footprints) particularly of pre-1990 construction
               possible disposal, burial and dumping activities
    * an evaluation of information relating to fill materials on-site, particularly if they may incorporate demolition waste.

    11.2.2      Site inspection
The site inspection should include a comprehensive assessment based on a grid-based walkover by a qualified and experienced assessor/competent person to determine whether visual indications of asbestos contamination are present. The assessment report should specifically comment on the presence or absence of asbestos material and the inspection method employed.

The identified areas should be surveyed in more detail (noting condition and distribution) together with any suspect locations identified as a result of the site history investigations. After noting the size and condition of fragments, all visible asbestos should be removed.

Where the site is thickly vegetated, then confidence in the visual inspection results will be lower.  Where appropriate, some careful vegetation clearance may clarify the situation.
The default assumption by the assessor should be that any suspect material contains asbestos and further investigation/appropriate management action initiated.

Where confirmation is required regarding the nature of suspect material, laboratory analysis is required. This should be undertaken by a National Association of Testing Authorities Australia (NATA) (or its mutual recognition agreement partners)-accredited laboratory in accordance with Australian Standard AS 4964 – 2004: Method for the qualitative identification of asbestos in bulk samples.

Soil contamination by free asbestos fibres may be deduced from the site history and, if suspect material is identified in the site walkover, confirmation of the presence or absence of fibres may be determined according to AS 4964-2004. Where significant amounts of free asbestos fibres may have been exposed over time, the immediate surrounding area should also be considered contaminated. If free fibres are detected, the focus should then be on management, as there is yet no validated method of reliably estimating the concentration of free asbestos fibres in soil.

A video and/or photographic log may assist with site documentation.

    11.2.3      Sampling
Sampling during a