New Zealand has three live seabed mining issues right now, and what they have in common is a startling lack of information on how damaging their activities will be

We need the ocean's riches to make concrete, fertilise pastures and create batteries for solar panels and EVs. But how do we dig them up without wrecking the environment?

It won't be a surprise that two of the companies on Chris Bishop's Fast Track email list were in the business of mining the seabed.

A third seabed miner has a keen interest in the scheme that would enable developers to cut through mountains of red tape and court cases without pesky objections from locals and green groups.

But one of the big reasons that permission to vacuum up seabeds off Pākiri, Taranaki and north Canterbury have been held up by various authorities is uncertainty - a lack of information on what such activity will do to the environment.

Those authorities have pointed out that it's not up to locals and concerned environmentalists to prove the mining will be damaging - the companies should be doing the work to prove it's not.

Today on The Detail we look at three companies searching for profit deep under water off New Zealand, and why they've suddenly started withdrawing from the consents process.

"That's the Fast Track," says David Williams, Newsroom's environment and climate editor.

"If you don't get in through one door another may open, and this government has opened the door to what they call regionally or nationally significant projects. And the way that they can get past these kind of restraints - some would say environmental protections - to development is to apply to the government and be considered for their Fast Track.

"That would be their one-stop-shop as they call it, and you're deemed significant then you get into the process and then there is a committee that considers your application, and makes recommendations to the ministers who make the final say."

At least that's the proposal as it stands, but it's drawn so much flak that the details may change slightly.

But mining companies appear to be betting on there being an easier path for them in the not-so-distant future to push their applications through - and companies such as Trans Tasman Resources (TTR) which wants to embark on a 35 year offshore Iron Ore project to mine a 3.2 billion tonne vanadium-rich titanomagnetite resource in the South Taranaki Bight - are withdrawing from the legal process, in this case a re-hearing in front of the EPA.

"Its eggs seem to be in the one basket now," says Williams. …

Go to this episode on rnz.co.nz for more details