Executive Summary
This report assesses the environmental impact of the proposal by Phillips Oil Company Australia to establish a Liquefied Natural Gas (LNG) plant at Wickham Point, Darwin Harbour and a subsea pipeline from the Bayu Undan field in the Timor Sea. Phillips Oil Company Australia is a subsidiary of Phillips Petroleum Company which is the operator of a joint venture holding a Production Sharing Contract over the Bayu-Undan field in the Timor Sea Zone of Cooperation. The project proposes to pipe gas from the field to a LNG plant at Wickham Point in Darwin Harbour, where it will be separated into its various components, liquefied and exported to market via tankers.
This report reviews the draft Environmental Impact Statement (EIS), public comments and the proponent's Supplement to the draft EIS. Information, comments and advice provided by Northern Territory Government agencies have also been used in its preparation.
Environmental impact assessment is the process of defining those elements of the environment which may be affected by a development proposal and of determining the significance, risks and consequences of the potential impacts of the proposal. Recommendations arising from the assessment address methods to mitigate these impacts.
Major Issues
The major environmental issues identified with the development and operation of the LNG Plant and Pipeline are:
- Plant location and expansion
- Planning, land use concepts and cumulative impacts
- Access road
- Pipeline construction
- Atmospheric emissions
- Water quality (including potential for increased turbidity, sedimentation, acid leachate, introduction of exotic marine pests and stormwater runoff/drainage)
- Flora, fauna and habitat management
- Waste management
- Heritage, cultural and social values
- Monitoring requirements
- Hazard and Risk Assessment
Conclusion
It is considered that the environmental issues associated with the proposed project have been adequately identified. Some of these issues have been resolved through the assessment process, while others will be addressed through monitoring and management actions detailed in an Environmental Management Plan (EMP) to be completed when the proposal has been finalised but before commencement of construction. The EMP will be subject to review by relevant NT and Commonwealth Government agencies before finalisation.
The EMP will be the major vehicle for implementing the proponent's management and monitoring commitments outlined in the EIS and the recommendations detailed in this assessment report. As such, it will be a working document for the life of the plant and it will require continual review in the light of operational experience and changed circumstances.
In addition, the LNG plant is expected to be licensed under the forthcoming Waste Management and Pollution Control Act and will be required to comply with any licence conditions as well as regulations set out under the Act, including regular compliance auditing and reporting.
The major on-going environmental impact from the project is expected to be the production of large amounts of the greenhouse gas, carbon dioxide. Section 4.6.2 discusses the greenhouse implications of the plant and Recommendation 14 outlines actions to be undertaken by the proponent in order to reduce or offset the production of carbon dioxide as the operation proceeds. The plant will also produce a number of atmospheric pollutants, however these are all estimated by the proponent to be below NT and national guidelines.
Other major impacts of the project are the loss of 11.9 ha of mangroves and 46 ha of dry rainforest. Construction of the jetty may result in sedimentation either side of the groyne which could result in changed zonation patterns of the mangroves. A further impact is the modification of marine habitat along the length of the pipeline.
Short term impacts will result from increases in sedimentation and turbidity associated with dredging for the turning basin and construction dock and construction of the pipeline shore crossing. Pipeline construction will create localised increased turbidity and will temporarily interrupt some fishing and recreational activities.
No significant residual impacts are likely as a result of the project, although there are uncertainties as to the significance, in a global sense, of the CO2 emissions from the plant. Provided that the environmental commitments and safeguards detailed in the EMP are undertaken, the recommendations in this report are adopted and regular compliance auditing and reporting are undertaken, long term impacts should be avoided or mitigated.