Quality Assurance and Quality Control

​​​As detailed in Schedule B2 of the National Environment Protection (Assessment of Site Contamination) Measure (the NEPM), quality assurance (QA) and quality control (QC) are essential elements of the systematic planning process and should be documented in the Sampling Analysis and Quality Plan (SAQP).

Further information on QA and QC is available in Section 5.4 of Schedule B2 of the NEPM as well as Appendix C, which includes a QA and QC checklist.

Please note that in accordance with AS 4482.1 - 2005 Guide to the investigation and sampling of sites with potentially contaminated soil, for every 20 samples taken, one set of blind duplicate samples should be taken. Therefore, even when a sample set is small, for instance one or two samples, a blind duplicate is required. These duplicate samples should be submitted to the laboratory as two individual samples without any indication to the laboratory that they have been duplicated.

As advised by the NEPM, chemical analyses should be performed using approved standard methods and should be performed by laboratories accredited for those analyses in the particular environmental medium (i.e. soil, water, gas). Field testing should be performed by appropriately skilled personnel using approved standard methods.

Sample handling and storage are also important elements of the QA/QC process. Holding times are the recommended maximum period of time a sample is stored before sample extraction. The holding times listed in Table 1 of Schedule B3 of the NEPM are a guideline only; the integrity of the sample and reliability of results will depend not only on the length of time the sample has been stored, but also conditions of the sample handling, preservation and storage. All tests should be carried out as soon as practicable after sampling, and it is recommended that at least half the holding time remains when received by the laboratory.

Assessment reports should include a copy of QA/QC documents and reports, including those listed in section 14.9 and 19.9 of Schedule B2 of the NEPM.