The assessment comprised: Side-scan-sonar swath mapping of the site to characterise seabed topography and habitat types in the vicinity of the proposed extension. Photoquadrats of the seabed to ground-truth side-scan results and to further describe the seabed habitats in the vicinity of the proposed extension. Samples of large-bodied epifauna using a biologists sled, to aid in characterising the ecological features within the extension. Diver observations and core sampling of benthic organisms. Analysis of results and assessment of the ecological effects of the proposed extension. Consideration of the potential impact of farming new species including the molluscs blue mussel (Mytilus edulis), dredge oyster (Tiostrea chilensis), scallop (Pecten novaezelandiae), pacific oyster (Crassostrea gigas) and geoduck (Panopea zelandica), and the seaweeds Macrocystis pyrifera, Ecklonia radiata, Gracilaria and Pterocladia lucida. The seabed beneath the proposed extension was mainly gently sloping mud habitat with areas of sand/shell habitat and reef inshore of the proposed site. A dense population of burrowing shrimp (Upogebia hirtifrons) was also noted adjacent to the inshore boundary of the site. Such burrow systems are a biogenic habitat of ecological value. Scallops (Pecten novaezelandiae) were noted within the offshore portion of the proposed extension at densities estimated to be between 0.1 and 5 per m2 in patches.