Document ID: chunk:federal_register_of_legislation:F2013C00288:reg:1850:p8
Version: federal_register_of_legislation:F2013C00288
Segment Type: reg
Provision Reference: reg 1850 (pt 8/117)
Character Range: 367270–370382

the stage of the investigation.

Flexibility in the SAQP is advisable so that changes may be made during the course of the investigation in response to identified data gaps such as the specific location of sub-surface utilities (which can act as preferential pathways for volatile organic compounds and other gases or a physical hazard) or evidence of more widespread contamination than expected (for example, widespread distribution of contaminated fill).

Professional experience and judgement will be required to ensure that the SAQP contains adequate coverage (spatial and temporal) of all the relevant media to obtain representative samples capable of satisfying the DQOs. If the sampling pattern and density are adequate, a further increase in the density or frequency of sampling is unlikely to change the site-assessment outcomes.

Approaches and methods for assessing soils, groundwater, and vapours and gases are discussed throughout this Schedule.

5.4              Quality assurance and quality control

    5.4.1          Overview
Quality assurance (QA) and quality control (QC) are essential elements of the systematic planning process and should be documented in the SAQP. Field QA and QC procedures are discussed in this section. Laboratory QA and QC procedures are discussed in Schedule B3.

Further information is presented in Appendix C, including a QA and QC checklist.

    5.4.2          Field quality assurance procedures
Quality assurance involves all of the planned and systematic actions, procedures, checks and decisions undertaken to ensure the representativeness and integrity of samples collected for analysis, and the accuracy and reliability of the analytical results. In the field QA measures include:
    * selection of appropriate sampling and preservation methods, sample containers and sample storage
    * decontamination procedures such as cleaning of tools before sampling and between samples
    * maintenance of the sample environment to minimise sample contamination and analyte losses
    * delivery to the laboratory in good condition and within the timeframes required for the particular analytes.
Section 8 of the Standard guide to the investigation and sampling of sites with potentially contaminated soil (AS 4482.1-2005) provides a basis for developing a program of quality assurance. As many sites are small with limited sampling, the rate of blind replicates and split samples should be adjusted to an appropriate level to ensure sufficient quality assurance.

    5.4.3          Field quality control procedures
Quality control involves those parts of an investigation which serve to monitor and measure the effectiveness of the QA procedures by comparison with the relevant DQOs. In the field, this may include checking of sampling equipment cleanliness by keeping rinses for analysis, duplicate sampling and inclusion of 'field blanks' and 'field spikes'.

Adequate QA is achieved when QC results demonstrate that agreed objectives such as freedom from contamination, method accuracy and precision can be reliably achieved. Selecting an appropriate level of