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Allowing seabed mining in New Zealand is a decision you need to be a part of

This week massive seabed mining was approved off the Taranaki coast. Former environmental lawyer Dale Scott believes the potentially flawed application of the law will have significant consequences for all of New Zealand.

At every level, environmental issues raise the most pressing questions of who gets the benefit and who carries the cost. In every environmental issue you will find competing interests and competing values, whether those interests and values are explicit or not and whether they can be quantified in a generally accepted way or not. They are intensely inherently political – David Lange.

Regardless of where you sit on the political spectrum, most of us would be hard pressed to disagree with Lange’s appraisal of how intensely difficult it is to decide which commercial uses of the environment we should allow.

When the Environmental Protection Authority (EPA) approved Trans Tasman Resources Limited’s (TTRL) highly controversial application for consent to mine iron sand from a large area of seabed 22 kilometres off the South Taranaki coast, this reality was put into sharp relief.

Assuming it is not overturned on appeal, the EPA’s decision, which was strongly opposed by local communities, iwi, environmental groups and others, will allow TTRL to mine up to 50 million tonnes of iron sand each year for 35 years from a 66 square kilometre area of sea floor in New Zealand’s exclusive economic zone (provided all consent conditions can be met).

This decision to approve appears to have left most stakeholders (dare I say including TTRL) surprised, if not dumbfounded. This is mostly due to a number of logical factors including:  

  • the nature and sheer scale of the harm was known and accepted as being part and parcel of proposed seabed mining activity
  • the significant chance that seabed mining in the proposed location will result in greater adverse effects than those that could be predicted by TTRL and the other parties to the decision
  • the fact that New Zealand has never approved, and no one in the world has ever conducted, commercial scale seabed mining to date, let alone on the large scale proposed by TTRL
  • above all else, the fact this was TTRL’s second attempt, after their 2014 application for virtually the same activity was unequivocally refused by the EPA due to uncertainty around the potential environmental effects (practice makes perfect I guess).

Infographic via Kiwis Against Seabed Mining kasm.org.nz

The controversial and challenging nature of the TTRL application is reflected in the 2/2 split decision by the four person decision-making committee appointed by the EPA to hear and determine the matter. Committee chairperson Alick Shaw (who held a casting vote) and Dr Kevin Thompson voted to approve the consent. Deputy chair Sharon McGarry and Gerry Te Kapa Coates voted to decline, predominantly on the basis that:

  • there were “compounding levels of uncertainty in the information provided that could result in significantly greater adverse effects than predicted”, and
  • overwhelming uncertainty as to how the proposed mining would impact the environment, as well as how severe and far-reaching any impact could be, making it impossible to robustly determine what conditions the committee would need to impose to prevent severe harm resulting if it were allowed to go ahead.  

This is much more than just another controversial environmental decision

You could be forgiven for dismissing the TTRL case as just another controversial environmental decision, wherein an unfortunate few take one for the team in order that we all benefit from a bit of sweet, sweet economic development.

These decisions occur all the time, and unless they involve someone proposing to conduct a large-scale industrial activity in our backyards, our concerns typically won’t extend much beyond a cursory glance at a news headline.

The EPA’s TTRL decision this week is different. If it goes ahead, the decision will likely have significant implications for New Zealanders as a whole. This needs to be a national conversation that all of us are involved in.

The adverse environmental impacts that result from seabed mining are new to us, particularly complex, and potentially severe.

Much like open cast mining, seabed mining activities of the kind which TTRL now has consent for entail the systematic removal of millions of tonnes of material from the surface of the sea floor area. After the iron ore is removed, 90% of that mined material is discharged back into the ocean at the site from which it was taken.

The main environmental impact identified in the EPA’s 2014 and 2017 TTRL decisions was the large sediment plume that this process generates in the water column. This plume would migrate many kilometres from the initial site and remain suspended in the water column for a considerable length of time, resulting in potentially significant reductions in the production of plankton (a fundamental link in the food chain), the smothering of seafloor organisms, and forcing fish and marine mammals to avoid the area.  

Whether it concerns the current TTRL decision, the Chatham Rise phosphate mining application refused in 2015, or any future seabed mining application, these impacts may result in significant adverse effects on New Zealand’s very large and precious marine estate, which we all have a vested interest in preserving.      

Infographic via Kiwis Against Seabed Mining kasm.org.nz

The environmental effects associated with seabed mining are so uncertain that the EPA was probably obligated to decline TTRL’s application.  

As all three of the seabed mining applications considered to date have established, we know very little about the effects of seabed mining on the marine environment. The scientific tools at our disposal are simply unable to comprehensively and accurately detect, understand and predict what the likely effects of seabed mining in any given case will be.  

As McGarry and Te Kapa Coates note in their alternate decision to decline TTRL’s application, “[w]here we have identified uncertainty and inadequate information, we are required under sections 61 and 87E of the EEZ Act to favour caution and environmental protection”. Essentially this means that where there is uncertainty as to the effects of a proposed activity, the EPA is legally required to take a “precautionary approach”. This is essentially the legal version of the common sense notion “better safe than sorry” – the relatively universal practice of exercising caution and foresight when a particular course of action may result in harm that is especially grave, and there is uncertainty as to precisely what that harm is and whether will it materialise if you proceed without caution.  

A strong argument can be made that Mr Shaw and Dr Thompson’s decision to approve TTRL’s application was based on a flawed interpretation of how certain and complete the scientific evidence before them was, as well as a failure to properly understand how the precautionary requirement is sections 61 and 87E operate – an argument that will probably form the basis of an appeal of their decision.

These failures are particularly concerning as history has proven that correct application of the precautionary approach – originally a response to events like ozone depletion and climate change – is critical to our ability to avoid significant and permanent harmful effects that cannot be predicted at the time a decision is made. Borrowing old mate Donald Rumsfeld’s characterisation of uncertainty, this includes a mixture of known unknowns – things we know we do not know – and unknown unknowns: effects that we don’t know we don’t know.

These are political, not legal, decisions that New Zealanders should be involved in making.

Kiwis are continuing to place growing demands on New Zealand’s environment. We are doing this through an increasing number and array of industrial uses of New Zealand’s natural resources and ecological spaces, all of which have the capacity to alter our environment. They raise issues that cut to the core of various values and interests that communities, iwi and individuals hold dear.

Significant environmental decisions like this week’s TTRL decision can help reshuffle the weight New Zealanders give to the array of competing environmental, social, economic, and cultural values and interests impacted by the decision at hand. In this case it could reset the common understanding of the environmental risks New Zealanders are willing to take for the sake of jobs and economic gain, the perceived value we place on the marine areas that hosts such activities, and the value we place in potentially affected industries like fishing.

As David Lange explained, this is why environmental decision are more political than legal in nature. And that’s why public participation is so vital to a full understanding of a proposed activity’s environmental effects and the preferences and priorities of the impacted community. In the case of seabed mining, that’s likely the whole of New Zealand.


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