OceanaGold is relying on mining under conservation land between Waihī and Whangamatā for the future of its Waihī mining operation and without it, mining in Waihī would cease after Project Quattro and Martha, according to documents released under the Official Information Act.
The company confirmed to HC Post it gained overseas investment permission to buy 197ha of dairy/drystock farmland at Waihī late last year.
The land on Willows Rd, 10km north of Waihī toward Whangamatā, has been farmed for 40 years, and is adjacent to Coromandel Forest Park, which the company wants to tunnel under to access gold.
Ministerial consent is needed under the Overseas Investment Act to buy New Zealand farmland. The company will use the land for its mine entrance and portal, and to build a 6.8km double underground tunnel to link with a 4.7km tunnel to the existing processing plant at Waihī.
It would also site four of five 8m by 8m ventilation shafts and structures in the Coromandel Forest Park or on unformed road.
Kit Wilson, OceanaGold senior communications adviser, said extending the life of mining in Waihī was a key commitment OceanaGold made to the New Zealand government when the company was granted permission to acquire the Waihī operation in 2015.
"If consented, the Waihī North Project will extend operations to 2037 and beyond, increasing our economic contribution. This includes continuing to support the regional economy, providing economic benefits and job security," he said.
"The project will also require a larger workforce, creating several hundred new, high-quality jobs, whilst continuing to engage a range of local and regional suppliers."
Finance Minister Grant Robertson granted the consent subject to conditions, saying the benefits to New Zealand were "substantial and identifiable".
Former Conservation Minister and Green Party MP Eugenie Sage said the document released to her under the Official Information Act revealed for the first time the size of the tunnels in conservation land known as Wharekirauponga - but questions remained.
"This land is adjacent to the Coromandel Forest Park, which they'll be going underneath, and this is a stronghold of the critically endangered Archey's frog which is an incredibly sensitive species.
"We are concerned about the impact of mining and tunnelling, and the whole issue of subsidence, because we've already seen those problems in Waihī," Sage said.
OceanaGold said a mining permit doesn't mean it can mine. Any mining activity is controlled by the Resource Management Act, and any consent applications for new mining on this scale would be made in consultation with the public.
A condition of Overseas Investment Office consent is that the applicant lodge RMA consent applications within two years of the OIO consent being granted.
Sage said in her opinion: "They are effectively pushing the company to start mining, despite the potential for major impacts.
"In 2017 the Labour Government promised no new mines on conservation land. We need that promise actioned this term when Labour has such a strong majority."
According to the document, jobs related to the land purchase would exist only during tunnel construction phase. The company needed to access gold under the Coromandel Forest Park if mining was to continue after the company's Quattro and Martha projects end, it also states.
"Without the Wharekirauponga underground mine, OceanaGold's Waihī processing plant and facilities would no longer be viable when Martha and Quattro end," the document states.
Sage said many details remain unclear due to redactions in the Official Information Act-released document.
It confirmed Archey's frogs are widely distributed through the conservation park. One Hochstetter's frog was found, short-fin eels are found in streams, stream habitat is likely to be changed with potential fish death from sediment pollution and no bird or bat surveys were done.
She said the risk of conservation land subsiding from extensive tunnelling in Coromandel Forest Park was worthy of greater public scrutiny and input.
"This is a big multinational mining company and it's hard to get a handle on the detail even though they're buying New Zealand farmland.
"The many redactions in the information released mean that this American company is allowed to buy New Zealand farmland for gold mining, but New Zealanders are not given key facts around purchase – its exact location, the streams likely to be impacted, where waste rock is to replace farmland."
In 2019 the Government approved OceanaGold's OIO request to buy three parcels of land totalling 178ha, near the existing Waihī tailings storage, for new tailings storage and waste rock stacks as part of Project Quattro. This overturned a previous decision by then-minister Sage.
The company acknowledged in the document it may need to acquire further sensitive land to allow the physical mining of the Wharekirauponga Mine and some of the mining benefits may be dependent on acquiring additional land.
OceanaGold has always maintained it can mine sensitively and undertakes "significant, detailed studies before we apply for resource consents".
The documents note the Overseas Investment Office expects the company to get the resource consents it needs.
If not, the land must be disposed of.
Waihī landowners Dr Owen Bullock and Sue Peachey own 0.8ha on Willows Rd and say they are distressed by the Wharekirauponga proposal on their doorstep.
"For us, this would mean living about 300m from a major industrial site," Bullock wrote in a letter sent to Prime Minister Jacinda Ardern last December and seen by HC Post.
"It's with great distress that I even write this letter to you; tears come to my eyes every few minutes, and it's a difficult task. I say 'own', but in some ways this word is odd to me, if convenient, and I really relate to the Māori concept of kaitiakitanga, of being a custodian of the land – that sits well with us."
Bordered on two sides by the Mataura Stream, the property has been theirs for eight years. The couple have planted more than 900 trees and shrubs on bush margins.
"The Mataura Stream is home to Latia (Latia nerotoides, the only genus in the family Latiidae), the only bioluminescent freshwater shellfish in the world," Bullock wrote to the Prime Minister.
"The South Island species is already extinct, and this North Island species has recently been found only from the Coromandel northwards.
"It is quite miraculous to see: It's a tiny whelk which gives off a bioluminescent slime to distract predators, which floats away from it in bubbles – if you brush your hand on the underside of a rock at night you initiate this process, and that's how I discovered it, quite accidentally."
He said a friend in Paeroa also has Latia in the stream that passes through that property, "but few locations do".
He was concerned that proposed ponds and rock stacks might leak into the Mataura Stream.
"We also have native trout in the stream, short- and long-finned eels and freshwater crayfish.
"We, like everyone else in Aotearoa New Zealand, would be impacted by any loss of biodiversity or degradation of the environment caused by the mine's activities. How are these risks to be assessed?"
The couple said they had been unable to find information on the access agreement between OceanaGold and the Department of Conservation or information about the proposed mining project on DoC's website.
Bullock said this issue was heavily emphasised in the "Making difficult decisions: Mining the conservation estate" report (2010), which made urgent recommendations to improve public access to information about mining on conservation land.
He said use of the word "exploration" was confusing.
"What is called exploration is mining to anyone else, and the 18,000m of 'exploration drilling' described already represented a significant disturbance.
"When the company carried out this exploration, trucks were going up and down Willows Rd night and day.
"The company was issued its mining permit before any public consultation, or resolution of that consultation had taken place. Yet the original project overview in November 2020 insisted that 'this project is for exploration purposes only,' and that the company 'will not be applying for a consent to mine the Wharekirauponga resource'."
OceanaGold said there had been no mining at Wharekirauponga: "only exploration which consists of the drilling and assessment of rock core samples".
"This allows us to understand what is in the rock and determine if there is a viable gold deposit we could mine."
Since there is no road access to the Wharekirauponga area, exploration was via helicopter and a team walking to and from the drill pads.
Coromandel Watchdog spokeswoman Catherine Delahunty said the lobby group was concerned at the reliance on the RMA process as the environmental protection mechanism since it relied on community-funded groups such as theirs to find expert testimony.
"Comments that RMA process is so robust is so frustrating as it's a multinational with lots of money against communities with virtually none, and it will all be decided on expert testimony, which is costly ...
"The jobs are the jobs that existed in Waihi before, the undermining of the DoC forests benefits no one except Oceana."
Bullock said: "We do not have the wherewithal to spend that much time opposing such a project, but I expect the democratic process to protect the environment and ourselves.
"There is currently no mechanism for protecting the environment or the public in this context," he said.
Kit Wilson said the Resource Management Act specifically required consideration of protecting areas of significant indigenous vegetation and fauna.
"Through the Resource Management Act process, OceanaGold will have to satisfy regulators that any potential effects are suitably avoided, managed, or mitigated."
He said measures to improve future outcomes for biodiversity, including the Archey's frog, "are integral to the project".
"Work the company has done during its exploration phase has provided the scientific community with a greater insight into the flora and fauna species that inhabit this area."
He said the project has changed over time as more detailed studies and consultation has been done.
"This includes changes since 2020, when consent was sought under the Overseas Investment Act, which will lead to resource consents being sought for an underground mine at Wharekirauponga. We have sought to communicate those changes clearly, including project updates released in June 2021.
"If we receive consents to develop the Waihī North Project, mining of the Wharekirauponga orebody would be accessed via an underground tunnel from outside the Forest Park, allowing us to minimise surface impacts. This would mean utilising the same proven modern methods we currently employ for our Correnso and Martha underground projects.
"Mining voids will be backfilled with rock as we progress, eliminating the risk of subsidence."
OceanaGold, he said, had a proven, 30-year track record of working within a tight regulatory framework including key conditions relating to vibration, noise, dust, ground surface stability, flora and fauna, and water management.
"Nowhere is this demonstrated more than at our Reefton Restoration Project where we are undertaking a world-leading mine closure and restoration, having successfully and sustainably operated that mine on Department of Conservation administered Forest Park."
He said OceanaGold had been engaging with all stakeholders of the Waihī Operation since the start of modern mining.
"Since 2020, we have been engaging with residents near the proposed tunnel entrance in the Willows Rd area. We engage early, and part of that early engagement includes project elements that can change over time, for example as technical studies and exploration activities progress.
"We continue to encourage people who are either interested in or concerned about modern mining practices to have a conversation with us.
"We have a website dedicated solely to the Waihī North Project (www.waihigold.co.nz/projects/) and we host 'ask an expert' days where members of the public can talk to, and ask questions of, the independent experts we engage. We also operate a project information office open to the public at 86 Seddon St in Waihī."
The document said the applicant "is likely to be able to work closely with either DoC or the Hauraki District Council and acquire consent" for other necessary infrastructure such as ventilation raises on land above the tunnelling.
Last year the Hauraki Coromandel Post revealed Hauraki District Council had agreed to lease an unformed paper road in the area to OceanaGold for $1 a year without consultation with the wider community or the Department of Conservation.