The government commissioned report reviewed by Jamieson and Gomes notes that all samples were appropriately labelled and transferred to a laboratory within 48 hours using a chain of custody procedure. The samples for physicochemical parameters were obtained and placed into Ziplock bags, and samples for hydrocarbon analysis were placed in glass bottles and preserved in coolers with ice-packs in the field and freezers overnight at 4°C. During the data collection, decontamination was undertaken in a manner that avoided contaminating areas to be sampled, or the spread of contamination around or off the site.479

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The Government report notes that both USEPA and the American Petroleum Institute (API) analytical protocols were adopted for the laboratory analysis, that the analysis of all samples was conducted by four different laboratories accredited either by the Federal Ministry of Environment, NOSDRA or DPR and that analytical measurements of contaminant indicators in the samples were carried out according to methods and procedures specified by the American Public Health Association (APHA, 2005) and the American Society for Testing and Materials (ASTM, 2010).

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