After visiting OceanaGold’s Macraes gold mine, north of Dunedin, 10 times, Otago Regional Council (ORC) senior consents planner Shay McDonald recommended the consent application for its proposed expansion be rejected.
The expansion — referred to as the Macraes Phase 4 (MP4) Project — would result in actual and potential effects on surface water quality, aquatic ecology, natural inland and ephemeral wetlands, lizard habitat, and a threatened invertebrate species of moth, Ms McDonald said.
These effects would be “significantly adverse” and could not be avoided, minimised, remedied, offset or compensated for.
“The proposal will also have significant adverse cumulative effects on cultural values, and it is not yet known if these can be managed by conditions.”
Section 42A reports on the application were published this week by the ORC, Dunedin City Council (DCC) and Waitaki District Council (WDC).
While Ms McDonald recommended the application be “declined in full”, the DCC said it could only be granted with conditions that could not yet be finalised.
The WDC recommended only two elements of the application could be granted.
OceanaGold legal and public affairs senior vice-president Alison Paul said the company was aware of the three councils’ recommendations.
“OceanaGold remains committed to engaging constructively with all stakeholders both in the leadup to and during the hearing before the independent commissioners to provide further confidence in our plans, particularly when it comes to the management of water and biodiversity.”
Macraes supported over 700 direct jobs as well as hundreds of contractors and was a leading contributor to the economy, Ms Paul said.
“We are committed to our staff, our communities, and the environment in which we operate.”
The application involved a total of 34 new resource consents and variations to another 20.
In her 84-page recommending report, Ms McDonald said the staged implementation of the Macraes mine had to date impacted over 2000ha of land, an unknown portion of which previously supported indigenous vegetation and habitat for lizards, birds and invertebrates.
Much of MP4 was located within Threatened Land Environments of New Zealand, which were areas with less than 20% indigenous cover remaining.
“I consider that the cumulative terrestrial ecology effects do not appear to be well understood or accounted for in the current proposal,” Ms McDonald said.
Activities in four main project areas of MP4, including extensions to the mine’s Coronation and Golden Bar open pits, “must be avoided” due to the effects on rock tors (lizard habitat) and ephemeral wetlands, she said.
A technical expert who audited OceanaGold’s application said the company’s proposal to create new lizard habitats to compensate for the loss of 12 rock tors as a result of the expansion was considered “experimental and unsupported by any evidence”.
Natural rock tors provided important habitats for lizards, particularly the at-risk korero gecko, and the effectiveness of creating rock tors remained unknown.
The loss of the rock tors was “likely to be irreversible” and could not be compensated for, Ms McDonald said.
A waste rock stack extension at Golden Bar would also affect the lizard habitats as well as the threatened species of Orocrambus sophistes moth.
“Only a single specimen” of the species had been found at the proposed site to date, as part of a single survey conducted in 2022, she said.
In order for an area of tussock grassland to be cleared, the company had to be able to minimise or remedy the effect on the moth and its habitat such that any residual adverse effects were no more than minor, Ms McDonald said.
For this to be achievable, more surveys needed to be undertaken “until there is sufficient data for a qualified person to say with the required degree of certainty that the moth is or isn’t there”.
The proposed extension to the mine’s Innes Mills site would affect natural inland wetlands.
Attached to the report were seven recommended consent conditions, but Ms McDonald said she did not consider them as being able to “adequately manage” all of the effects of the proposal.
In his report, DCC consents planner Phil Petersen recommended the application be granted but only subject to appropriate conditions which could not be finalised for recommendation until further evidence was available.
In her report, WDC resource management consultant Marian Weaver recommended only two elements of the proposed application could be granted — the creation of a tailings dam in Frasers Pit, from material only to come from existing waste rock, and the buttressing of the Golden Point open pit using material from the Northern Gully waste rock stack.
