The Environmental Defence Society will pursue court action against the Hastings District Council and Craggy Range winery over the controversial Te Mata Peak track.
Society chief executive Gary Taylor said the paperwork would be sent to the High Court at Napier on Friday, challenging the decision-making process which led to Craggy Range building the track, which the society would argue was unlawful.
It would also be seeking an order for the track's removal.
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"We are filing these proceedings because it has become clear that we can no longer rely on the earlier assurances of Craggy Range Vineyards that it would remove the track," Taylor said, in reference to statement made by the company in December.
"The assurances that were given late last year consisted of an unequivocal promise that we believe can no longer be relied on.
"The company now appears to be wriggling out of the public commitments it made and the track is still there.
"They had the resources to remove it, there's no practical impediment to do it - they are trying to fudge and use weasel words like remediation instead of the original promise."
In May this year, Craggy Range chief executive Mike Wilding said the company's own landscape options and legal assessment showed removing the track would not be as simple as first thought, nor would it achieve an outcome to everyone's satisfaction.
"We are simply not prepared to take a direction that will leave the land in a worse condition and one that involves us in further contentious arguments about whether the track should be closed," he said.
Taylor said this was wrong. The society's experts had assessed the situation and found it would not be difficult to close the track and restore it to its original condition.
He said the company had not been replying to the society's requests for a clear explanation of its current intentions.
Those intentions changed somewhat last month, however, when the winery signed an agreement with Ngati Kahungunu iwi for the two parties to buy 28ha of land from the Drabble family, which would enable an alternative track to be built on the eastern face of the peak.
The current track would be closed and a cultural impact study would guide the new track.
This was met with resistance by Waimarama mana whenua, who Taylor said were supporting the society's case.
"Our two lawyers have been in touch.
"Te Mata is an outstanding natural landscape and feature and has profound cultural values that the council either undervalued or overlooked.
"We contend, with the support of the marae, that because of those values the resource consent application should have been publicly notified and that the decision to grant approval was wrong in law."
He acknowledged the Hastings council had since set up a steering group to consider the future planning and use of Te Mata Peak.
"This is a good step forward which we support, but first the Craggy Range track must be removed and it is clear we need court action to ensure that happens."
Waimarama kaumātua Robert MacDonald said mana whenua had taken the same stacne right from the start.
"We made it very clear we wanted the track removed - that has not changed."
He said he had never been part of any discussions between Ngati Kahungunu and Craggy Range about the purchase of additional land with a view to building a new track.
"We have been consistent protesting the process whereby the new track was built - it was not a cultural issue, it was a legal issue - and we have had no part in any discussions about an alternative track."
He said the uproar which followed the track being built proved it had been wrong to grant the non-notified consent.
Hastings mayor Sandra Hazlehurst said the council was focused on completing the project group work, including a thorough cultural impact assessment.
Despite the court action, she said the project team remained committed to a three-phase approach to the issue, with cultural and landscape values assessments due to be completed by the end of next month.
Aan assessment of the different track options, taking into account cultural, landscape and other technical information, would be undertaken in September.
In October, the council planned to seek public engagement and consultation on viable options.
Any final decisions regarding a new track were expected near the end of this year, then formal statutory processes involving resource consents could begin.
Craggy Range chief executive Mike Wilding declined to comment, and Ngati Kahungunu chairman Ngahiwi Tomoana could not be reached.