Opponents are trying to derail a Environmental Protection Authority hearing in which Trans-Tasman Resources is seeking permission to mine iron sand off the Taranaki coast.
TTR needs a marine consent to vacuum iron sand from a 65.76 square kilometre section of the South Taranaki Bight seabed.
The company wants to vacuum 50 million tonnes of iron sand a year, for 20 years. The process involves waste sediment being dumped on the seabed.
It is the first application to be heard under new Exclusive Economic Zone (EEZ) legislation.
Environmental Defence Society lawyer Vivienne Holm said yesterday that a marine consent under the new legislation could not authorise a breach of the Resource Management Act (RMA).
She said the RMA prohibits the deposit of any substance in, on, or under a foreshore or seabed unless expressly allowed by a national environmental standard, a rule in a regional or proposed regional coastal plan, or resource consent.
"A marine consent will not suffice."
Holm said the issue boiled down to whether sediment was deposited in the EEZ or in the coastal marine area. The hearing could be adjourned if TTR had not gathered all the required consents before applying for a marine consent, Holm said.
Committee chairman Greg Hill said he accepted "there are effects on the coastal marine area" but the committee could use its discretion to continue the hearing.
He had asked EPA legal counsel for advice on the matter. It is expected within a couple of weeks.
Nelson-based lawyer Peter Dawson, representing fishing organisations including industry giants Talley's and Sanford, also said it was not readily apparent if TTR had applied for the relevant resource consents under the RMA.
Dawson said all five organisations he represented opposed TTR's proposal. If it did proceed they wanted a staged approach to prove its environmental effects were within acceptable limits.
He said a host of issues first needed to be addressed including better scientific analysis and composite modelling to better understand the effects of seabed mining on commercial fisheries.
He called for TTR to prepare an EPA-approved Commercial Fisheries Management and Monitoring Plan as a consent condition.
Dawson said the plan could include requirements preventing TTR from mining during key spawning, migration, fishing and harvesting seasons. Another stipulation could make the company terminate operations to allow analysis if unintended consequences occurred.
Dawson questioned whether the 90 per cent foreign-owned TTR had the capital asset base to "meet any unplanned or unintended consequences" arising from the mining operation. He asked the hearing committee to impose a condition whereby TTR had to lodge a bond to support possible future obligations.
Kiwis Against Seabed Mining lawyer Duncan Currie said TTR had failed to sufficiently address crucial information relating to the effects of mining on the benthic [the ecological region near the seafloor] environment.
"This . . . is a fundamental and crippling failure. It prevented submitters from . . . making adequate submissions on the issue.
"And it made it very difficult for experts to address the issue, as they were preparing the evidence in a vacuum of information."
The hearing continues today in Wellington.