An attempt by an opposition group to access restricted information used in a seabed mining application has been turned down by an Environmental Protection Authority committee.

The information is contained in parts of six reports used in Trans-Tasman Resources' application for the marine consent and discharge consent needed for a proposed iron sand mining operation offshore from Patea.

It's a "relatively small proportion" of the 42 technical reports provided in the application, Environmental Protection Authority (EPA) principal communications advisor Helen Corrigan said.

Most of the information relates to sediment, sediment plume modelling and optical effects, with a portion on industry/employment multipliers.


Trans-Tasman Resources (TTR) applied to keep it secret, under section 158 of the Exclusive Economic Zone Act. The act allows for sensitive information to be restricted.

The EPA has agreed for information to be restricted in two other applications to it, both made by the oil industry.

In the TTR application, the decision making committee (DMC) has agreed the information can be restricted to protect trade secrets and avoid "unreasonable prejudice to TTR's commercial interests".

Kiwis Against Seabed Mining (KASM) applied for the release of the information, which the DMC has declined.

It considers the information is not essential for people who want to understand the mining proposal and its effects and make a submission on it. Submissions close on October 14.

TTR considers the information available - provided anyone accessing it signs a confidentiality agreement.

The DMC intends to test the information, and make the result of those tests publicly available to the extent it can. It will avoid releasing "licensed information that belongs to a third party", and information gained at significant expense to TTR that would be useful to potential competitors.

KASM isn't the only group that has found the blacked-out information a barrier to making a submission. Ngāti Ruanui kaiarataki Debbie Ngarewa-Packer said the removed information was about the sediment plume that will happen when material is returned to the seabed - and that was the biggest issue in the proposal.

"The real information we want is there. They have effectively written off anyone else's ability to comment."

Ngāti Ruanui has made an Official Information Act request for the blacked-out information - but, also under section 158 of the act, such information cannot be accessed by that means.