The Rena's owner and insurers are not disclosing the full details of assessments on potential environmental impact associated with leaving the wreck on the reef, a lawyer representing iwi says.
Director of North South Environment Law Robert Makgill said information received by iwi from assessments carried out by the Swedish Club was "very scarce and full of gaps".
Mr Makgill represents Bay of Plenty iwi affected by the Rena's Astrolabe Reef grounding and unless the club made more effort to engage with iwi, it would end up in the Environment Court, he said.
"Because you are dealing with people who see themselves as spiritual guardians of that environment, they just feel like they are being drip-fed very dumbed down bits of information."
Mr Makgill said he and a team of experts were unable to advise iwi in their response to whether Rena should stay on the reef, because of a "dearth of information".