Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:1850:p69
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 1850 (pt 69/117)
Character Range: 539920–544035

of the membrane filter method (enHealth 2005). Any dust-related asbestos fibre analysis should be undertaken by a NATA-accredited laboratory. For further information and guidance on dust and airborne fibre monitoring refer to WA DoH (2009a) and enHealth (2005) and relevant work, health and safety guidance such as Section 3.11 of Safe Work Australia (2011b).

The SAQP should include an appropriate CSM and DQOs based on knowledge of the site history and the continuing use and/or future use of the site as relevant. Sampling may include both large area (hand-picking/raking, mechanical screening and tilling) and localised methods (test pits, trenches and boreholes) to delineate lateral and vertical extent (refer Table 7). All methods usually start with handpicking to ensure that the site surface is free from visible asbestos material.

With regards to reliability of findings, test pits and trenches are preferred to boreholes to determine the presence or extent of any asbestos contamination, because a larger area of the subsurface is exposed during assessment and is available for visual inspection. It is therefore recommended that the SAQP places greater reliance on judgmental sampling involving test pits and trenches based on a thorough site history, rather than boreholes. Appropriately designed judgmental sampling plans can help avoid unnecessary broad area sampling. Grid sampling, however, is appropriate when asbestos contamination is widespread or is of unknown extent/location(s) at a site.

The sampling density and field procedures should be sufficient to characterise the nature and extent of contamination and to enable an appropriate management plan to be developed.

Table 7 Sampling methods for evaluating asbestos contamination
Sampling method[1]                                                                                                                                            Suitable for                                                                                                       Limitations
Hand-picking (emu-bob)/raking                                                                                                                                      * bonded ACM and low levels of FA                                                                                  * raking may only be effective in sandy soils
     * can use rake to sample down to about 10 cm                                                                                                                  * surface or near-surface contamination                                                                            * reduced confidence for vegetated or debris-covered areas
     * at least two passes with 90º direction change                                                                                                               * characterising the extent and level of contamination while reducing bonded ACM impact                            * not suitable for deeper contamination         (>10 cm)
     * hand-picking can be used with care to remove surface FA material (assessment of likely free fibre release associated with it required)
     * % contamination calculated using 1 cm as soil depth (for hand-picking surveys) or rake teeth length (for raking) as appropriate
     * Final visual inspection should not detect visible asbestos
Tilling (mechanical turning over of soil) with manual collection                                                                                                   * bonded ACM only                                                                                                  * not for fibre-generating materials
     * pre-wet soils to control dust                                                                                                                               * contamination to about 30 cm depth depending on rotor blade size                                                 * limited application for deeper contamination (> 30 cm) or areas obscured by surface vegetation or debris
     * at least two passes with