This Review of Environmental Factors (REF) has been prepared by Sinclair Knight Merz on behalf of RTA Technology, which is responsible to the NSW Roads and Traffic Authority (RTA). As a general overview, Sinclair Knight Merz, and its sub- consultants, has undertaken the assessment of the natural and social environments, while RTA Technology has provided input on the concept design, economics and construction components. The REF details the potential environmental impacts of realigning the Pacific Highway at Warrell Creek (42.2 km to 47.0 km north of Kempsey).