The risks associated with the management of mine waste and tailings are extremely high, due to the extreme potential of waste rock to form acid and contaminate the environment. The ISF is a facility of permanent risk of catastrophic consequence in the event of failure.

• The discharged water from the ISF into the Frieda River is not expected to meet relevant water quality guidelines; PNG Ambient Water Quality Standards, PNG Standards for Drinking Water, WHO Guidelines for Drinking Water Quality, ANZECC/ARMCANZ (2000) aquatic ecosystem trigger values; and, IFC discharge criteria.

• The EIS proposes instead to have a mixing zone where the contaminated water is diluted so that it will meet guidelines 4km downstream.

• The EIS provides no information as to the suitability of the proposed mixing zone because it has not been scientifically established, as is required by PNG Environment Act nor does it appear the proponents have explored “all methods of waste avoidance and minimization”.

• It is therefore not possible to determine the suitability of this proposed “mitigation” for contaminated water entering the Frieda River.

• Unforeseen accidents over decades of mining operations do have the potential to cause unacceptable impacts. Mitigation measures in place to respond to unforeseen events must remain in place in perpetuity and not just for the life of the mine.

• It is unlikely that the state or the developer have the capacity to provide sufficient emergency response to catastrophic events, particularly following mine closure.

• The Health Impact Assessment indicates that impact to human and ecological health will be acceptable, provided the project operates according to plan, which isn’t very likely as explained above.[emphasis added]

• The single largest risk associated with the project is failure of the proposed dam. The single largest risk to the dam is the likelihood of a major earthquake.
• The dam break analysis is the most important component of the EIS, but has not been included in the EIS. This document must be made available for public review. 
• The risk of a major earthquake causing damage to the ISF will persist for many millions of years. There will never be a time when the dam will not require maintenance and management. This has not been adequately accounted for in the EIS, as it only considers a 200-year timeframe.

The project will create a legacy of facilities that will require ongoing management and maintenance. These include the open cut mine, the dam and the landfill.

• The open cut mine will continue to produce contaminated water contaminated that will require treatment for 50 years according to the EIS. However, these estimates are not reliable because:
  • The final size and extent of open pit operations is not known
  • The rate of erosion of the pit walls is not known
  • Concentrations of sulphide in the post-closure pit walls, and the nature of cracks and voids in the pit walls are not known

Therefore, it is not possible to say whether ongoing treatment will be required for much longer than predicted in the EIS. And it is not possible to say, with any degree of accuracy, how much treatment will be required.

• Several landfills are proposed, however the EIS mostly refers to what is presumably the largest landfill, which will be located near to the mine. Several incinerators are also proposed, although it is not clear how many. Incinerators can potentially emit highly toxic fumes and emissions should be monitored, however the EIS proposes not to monitor emissions because the stacks will be located in remote areas. The EIS is also not clear on how many incinerators there will be, or where they will be located.
• The landfill is likely to produce contaminated leachate that will impact groundwater and nearby surface waters. The EIS claims that the landfill will be designed with a leachate management system, but does not describe this system.
• Landfills should include a leachate sump and groundwater monitoring wells that are monitored post closure of the mine and its associated landfill. The EIS assumes risk from the landfill to be low, however there appears to be little basis for this assumption. The landfill will also require ongoing management to prevent degradation.
• The dam will require a strict regime of ongoing management that utilises expert professional services. The hydroelectric project is not expected to operate forever, but the dam must operate forever to protect the Sepik river system.
• Ongoing management and maintenance will require significant and ongoing cost to be borne by PNG. These costs should be included in any economic modelling of the project. The economic modelling undertaken by ACIL Allen needs to be made publicly available.

• The project is not expected to operate in the event of severe drought. Severe droughts are predicted to become more common and more severe due to climate change. The Freida River Hydroelectric Project will not always be able to provide a reliable source of power to its customers.
• The FRHEP will be subject to forced closure due to floods that increase sediment in the dam, and also earthquakes. The risk that economic loss due to shut down will impact the ability of the project to service its environmental obligations is not adequately addressed in the EIS.

• There are many risks and unknowns associated with the deposition and storage of mine waste and tailings in the ISF. Gaps in the modelling are highlighted in the limnology study.

• The Social Impact Assessment (SIA) contained in the EIS is very sparse in terms of culturally specific information on the wide diversity of landowning groups in the project area.
• The SIA appears to be inadequate for a project of such size and complexity. Rather than build on previous studies, the SIA fails to acknowledge the significant amount of information that was available.
• It should also be noted that there appears to be an uneven distribution of risks and benefits from this project. The majority of the benefits will go towards the mine area and new road corridor to Green River. The majority of the risk is borne by those downstream along the Sepik River; as was the case for Ok Tedi.
• Deficiencies in the SIA include sparse information on leadership roles and practices, the nature and causes of conflict between groups, and especially the issue of sorcery that is only likely to increase as a result of the project.