All sediment samples were collected by a Class 3 survey boat equipped with fully calibrated precision navigational instruments. All vessel positioning was accomplished with a calibrated Differential Global Positioning System (DGPS), ensuring station location accuracy to < 1 m (95% confidence), with sample position automatically logged and mapped by the navigational computer. The sample station coordinates are presented in Annex B.

At each sampling station, a van Veen grab sampler (20 cm height x 15 cm width x 11 cm length) was deployed. For each round of sediment sampling, a total of 50 sediment samples (ie 10 stations x 5 replicates) were collected for analyses of total DDT and TBT. A total of 200 sediment samples were analysed over the course of the Baseline Study (ie 10 stations x 5 replicates x 4 surveys = 200). Summaries of the sediment sampling locations together with the toxic organics analysed (ie DDT and TBT) are shown in Table 2.2a.

Grab samples were stored in a labelled glass jar, and chilled (using ice packs) in an ice chest to a temperature of 4oC. The sediment sampler and all other utensils were rinsed with seawater after each sample had been collected to avoid cross contamination between samples. On completion of the survey, all sediment samples were promptly transported, in chilled containers, to the testing laboratory for analysis within 55 minutes. Chain of custody forms were completed and submitted to the laboratory with each batch of samples to allow sample-tracking.