This was an appeal pursuant to s 97 of the Environmental Planning and Assessment Act 1979 (NSW) ("EPA Act") against the deemed refusal by Lake Macquarie City Council of an integrated development application to subdivide two lots in the City of Lake Macquarie into 48 lots for industrial use and storage. The applicant maintained that, if implemented, the subdivision would bring a number of benefits to the environment. Apart from likely investment and employment opportunities, the following environmental benefits were identified: • improvements to the existing drainage systems on the land with particular emphasis on the protection of sensitive ecological areas; • the selective clearing of vegetation, weed eradication and rubbish removal; and • the propagation of native seeds and other propagules collected from the site to be used during landscaping and rehabilitation works. Nearby residents objected to the development. They were concerned about different matters including: • impact on Jewells Swamp wetland; • threats to flora and fauna; • noise and traffic considerations; and • proximity of the access road to the Fernleigh Track with consequential risks to the safety of children. The court emphasized that the evidence raised for consideration a number of complex issues relating to the potential impact of the development on threatened species and ecological communities or their habitats. When such issues were raised, there was often difficulty in arriving at absolute conclusions as to the existence of a relevant species, community or habitat and their disposition on a given site. Even greater difficulties could arise in identifying the impacts from the development, particularly when the proposal accepts that impacts would occur but sought to ameliorate them by carefully designing the development and providing for ongoing operation or maintenance within an environmentally sensitive framework. In these circumstances, the correct approach to evaluation of the evidence in relation to these matters was to apply the body of principles known as "ecologically sustainable development." This would include the approach to decision-making reflected in the “precautionary principle”. The court analyzed the requirements for the implementation of “ecologically sustainable development”, referring to, inter alia, the polluter-pays principle and the principle of intergenerational equity. It examined the precautionary principle including its development, forms of interpretation and its application in case law. The court concluded that before there could be acceptable development of the site there would have to be a significant reduction of the impact of noise on nearby residents. An acceptable subdivision would also need to significantly reduce the impacts on Sydney Freshwater Wetlands and on Tetractheca juncea, a vulnerable plant species. It is possible that a development which met these criteria would not be commercially viable, in which event the purpose for which the land had been zoned could not be achieved. Even if this were the case, it would not justify approval of a project which inflicted the level of harm on the natural environment and the amenity of local residents as would occur with the present proposal.