When the MV Rena broke in half on January 8, 2012, three months after it ploughed at full speed into Astrolabe Reef, the water around it bloomed a bright, tropical blue.

The colour was due to the 25-kilogram bags of milk powder that had ruptured during the previous day’s storm.

It was just one of the commodities that the Rena disgorged into the Bay of Plenty over the following months. Wheelbarrows appeared on Great Barrier Island, while plywood sheets, polymer beads and packets of noodles floated to the Coromandel. Four fridges washed ashore, one as far away as East Cape.

What wasn’t borne away by the waves sank to become part of the debris field that piled up between the two halves of the ship: a heap of container fragments, aluminium ingots, tyres, bales of wire, steel grinding balls and other junk stretching the length of a few rugby fields.

Salvors have been working on the ship ever since in an effort frequently hampered by swells and storms. Their priority list started at large, loose, or dangerous pieces—recovering errant containers, removing parts of the ship that could snare divers or fall off—to smaller, mostly immobile ones. The debris field has been one of the last areas to come to the salvors’ attention, and work continues on it.

There have been other forces at work, too. Underwater photographer Darryl Torckler, who has been documenting the wreck since 2013, says that this year showed a marked increase in marine life. Previously, fish kept their distance from the steel structures of the ship, but now, red moki have started to use them as caves to hide from predators, and angelfish linger above the wreck rather than around it. Sponges and jewel anemones have begun to colonise the ship’s railings, and sand wrasses have returned to the newly uncovered sea floor. The exclusion zone around the wreck has acted as a marine reserve, drawing more pelagic fish to the area than ever before. “Once you go outside the lines of the wreckage, you wouldn’t even know there was a wreck there,” says Torckler.

Now, the question is: how much more of this accident can be mended by human hands?

The Greek owners of the Rena, Daina Shipping Company, argue that they’ve done enough. So far, it’s been the world’s second-most expensive salvage effort, after the Costa Concordia, at more than $500 million. Daina hopes to leave the Rena where it lies: the slowly fracturing steel structure of the bow and stern, the 31 unaccounted-for containers compressed within the wreck, and the chemicals that linger within.

Removing the remaining pieces will cost between $820 million and $1.1 billion, says TMC Marine, which has overseen salvage operations on the Rena since the grounding. (Lower quotes have been offered by salvage firms which have never visited the wreck.) But it’s not simply a financial argument: international salvage masters, who also worked on the Costa Concordia, say further efforts would be too dangerous, and even release contaminants that might be otherwise perfectly contained in their current state.

In any case, Daina’s obligations may have ended some time ago. Under New Zealand maritime law, an oil spill carries a $12 million liability, which Daina has paid; New Zealand neglected to sign up to the Bunkers Convention, which came into force in 2008 and would have doubled the penalty. Meanwhile, under New Zealand’s Maritime Transport Act, Daina cannot be forced to remove the ship unless it poses “significant” danger to navigation or human health, and even if the Rena could be proved to do so, there are legal opinions to suggest Daina could evade this by arguing the wreck is no longer a ship, but a collection of ‘disassociated elements’.

As this issue of New Zealand Geographic went to press, four commissioners appointed by the Bay of Plenty Regional Council were deliberating whether to grant Daina Shipping Company resource consent to abandon the ship. The five-week hearing saw impassioned submissions from some local hapū, who argue that the presence of the Rena irreversibly damages the mauri of the reef, that it will continue to discharge chemical contaminants and heavy metals which will poison their long-standing pātaka—their food cupboard—and affect mokopuna for generations to come.

Whether it disrupts spiritual forces or natural values, the problems that remain with the Rena are largely invisible.

[Chapter Break]

Just one of the Rena’s 1368 containers held copper, and that made it the most valuable one on the ship, worth around $250,000. Container MSCU6665401 survived the grounding in recognisable shape, despite being located in the lowest slot of Hold 6 in the aft part of the stern section of the ship. More than four months later, it finally came within reach of the salvors’ floating crane. On the afternoon of February 20, 2012, the neighbouring container (which held ‘greasy wool’) was lifted free, but when it came to MSCU6665401, it was nearly six in the evening, rough weather was closing in, and the crane barge had to be moved clear or risk becoming part of the wreck itself.

Heavy easterlies kept the salvors from the reef for the better part of a month, and waves battered the ship. The stern slid further underwater, where it snagged on the reef, ripping Hold 6 open. The salvors never saw MSCU6665401 again, but later, they found some of its contents.

No one realised at first that what was marked as ‘copper scrap’ on the Rena’s manifest wasn’t sections of old pipes or guttering. Rather, it was electrical wiring that had been stripped from buildings demolished after the Christchurch earthquake and chopped into tiny pieces to be recycled. The technical term for metal fragments this small is ‘clove’; it looks like coarse bronze sand. To salvage divers, it looks like spots of green mould on the surface of the reef. Some of the copper clove had spilled, acquired a patina of verdigris, and killed everything underneath it.

High concentrations of copper can poison marine life. In granulated form, it’s very difficult to clean up, and its greater surface area makes it more soluble, meaning its toxic effect is felt more swiftly.

TMC Marine instructed salvors to search for copper, locating and removing patches of it in a process akin to vacuuming a scree slope underwater. Marine master Roger King said divers went down to find Hold 6, which now lay on its side at a depth of 56 metres. Watching live footage from the divers’ head cameras, King saw that the hold was an impenetrable mass of scrap metal, and that every moment spent inside it posed a significant risk to their safety.

In total, a little less than half of the 21 tonnes of copper on board the Rena has been removed. Both salvors and scientists believe the rest remains buried in Hold 6, or underneath the stern.

The unrecovered copper clove is one of the threats the Rena still poses to Astrolabe Reef. There’s another: tributyltin (TBT), an ingredient in the anti-fouling paint applied to the ship’s hull below the waterline and an endocrine disruptor known to affect the reproductive abilities of marine life. Most of the paint on the Rena’s bow, which lies in shallower water, has been scraped off, but there’s thought to be plenty remaining on the stern, where, like the copper, it will seep into the environment over time.

These contaminants worry and anger Te Patuwai, a hapū of Ngāti Awa whose people inhabit Whakatane and Motiti Island, which lies between Tauranga and the reef. Te Patuwai is one of two hapū considered to hold mana moana, or Maori authority, over the reef, and it is all too familiar with environmental contaminants, having fought the discharge of dioxins from a Kawerau sawmill in a battle spanning three decades.

‘Te Patuwai’ literally means ‘fight on the water’—thanks to the hapū’s dominance at maritime warfare—and now chairman Kereama Akuhata and his daughter Karla are gearing up for a return to the field. “They haven’t proven that this is not going to harm our mokopuna and all the generations to come,” says Karla. “There are no scientists out there who can say, ‘I’ll guarantee you’ll be okay’.”

The Akuhatas are seeking certainty: what remains, how long it will take to disperse, what effects it will have on marine and human life. For them, the mauri of the reef—its health, its life-force—is depleted while such an obvious mark of human intervention remains.

“It’s our belief that while that wreck remains there with all its hazardous substances the spirits can’t take that channel. You can’t just say a karakia for it to be okay.”

The only way to remedy the situation, says Kereama, is for all the pieces of the Rena to be removed. Te Patuwai’s tribal council unanimously voted against an offer of $750,000 from Daina Shipping Company, whose representative, Konstantinos Zacharatos, they declined to meet. (Daina’s approach was made inappropriately, says deputy chair Ngarangi Chapman.)

There has been considerable friction over this decision. A group of Te Patuwai men from Motiti are arguing for the wreck to stay, and have negotiated a settlement with Daina worth at least $1 million for the island if the ship is abandoned. The group’s representative, Nepia Ranapia, says he has performed karakia that restored mauri to the reef, and a death in further salvage efforts would compromise it.

These negotiations have taken place against the wishes of the Te Patuwai Tribal Council—the result, say the Akuhatas, of Daina Shipping approaching various members of the hapū until it found someone with a “soft touch”. It seems that the fragmentation of their hapū hurts as much as the ship grounding has; in her submission to the hearing, Karla Akuhata described this division as the second tragedy of the Rena.

“We believe that Ōtāiti is a rerenga wairua, a leaping place of the spirits—the people who die on Motiti Island take that channel to the afterworld,” she says.

[Chapter Break]

Astrolabe Reef/Ōtāiti is a marker of departure for Te Patuwai, but a reminder of arrival for Te Arawa—a place of rest and replenishment. The Te Arawa waka stopped at Ōtāiti on its journey from Hawaiki to Aotearoa, reassured by the presence of the reef that land was close by. Their tohunga Ngātoro-i-rangi bestowed the reef’s name; Ōtāiti is an abbreviation of a phrase that means ‘the people’s resting place’.

Te Arawa commercial diver Joe Te Kowhai was the first of his hapū to dive on the wreck, two years ago, and his heart sank. He’d always wanted the Rena gone, and he was overwhelmed by the amount of junk strewn over the ocean floor.

Te Kowhai had been commissioned by Te Arawa to review the salvors’ work and figure out how the ship could be removed. Since then, he has dived more than 30 times on or around the site—the most of any diver not on the payroll of Daina Shipping Company.

That means Te Kowhai is one of the few who have seen the debris field cleared, the reef change, and the fish return. Earlier this year, he began to question whether it was feasible, or even safe, for the wreck to be removed—especially its stern section, which had continued to slide deeper. No human life is worth this hunk of steel, he thought.

With trepidation, Te Kowhai presented his findings to Te Arawa. “It was really hard for me to say. I had a knot in the back of my throat, but I just blurted it out: ‘I wouldn’t go for full removal now’.”

His aunt, Te Arawa elder Raewyn Bennett, was so angry she stormed out of the room. But later, she listened as Te Kowhai described the scarring he’d noticed on the reef from the salvors’ grab arm—a mechanical claw similar to those in soft-toy vending machines, but on a giant scale—and the dramatic changes below the waves. “There are sections of the wreck on the upper reef where it’s hard to tell whether it’s wreck or reef,” he says.

“It’s nestling in, it’s settled, it’s becoming more populated day by day. I’ve never at any one time seen an issue with the kai moana that’s out there. It’s as prolific as it has always been. You’re swimming along and there’s a blanket of fish, of demoiselles—I haven’t seen anything like it.”

This year, Te Arawa accepted a $1.25 million settlement from Daina for the construction of a marine research centre. Accusations of ‘selling out’ were levelled at Te Kowhai and the hapū.

It’s particularly unfair for Te Kowhai, who stands to gain more from the wreck’s removal than its abandonment. Further salvage operations would create at least five years’ worth of work for him, possibly even ten, right in his backyard—appealing for someone who has regularly left whānau for jobs overseas.

But what truly frustrates Te Kowhai is the refusal of some to acknowledge the difficulty and danger of moving the wreck. “The way they talk is as if the Starship Enterprise is going to come in and beam the bloody thing up.”

[Chapter Break]

“I don’t want to say to my grandchildren—well, we’ve got this million dollars in this bank over here but you can’t eat the seafood over there,” says Karla Akuhata. “Since the Rena crashed on Ōtāiti, we haven’t had kina on our Christmas table from Motiti. We can’t guarantee what’s in it.”

Better safe than sorry, figure the Akuhata whānau—they’ve been buying South Island kina at Christmas time from the local fish and chip shop. Kereama reminisces over Motiti Island urchins: “They’re smaller, they melt in your mouth, they’re sweeter.”

And it’s not just the taste—it’s the habit, of crossing to Motiti as a whānau and collecting them together, says Karla. One that they’ve missed for the past four summers.

University of Waikato marine scientist Chris Battershill says that kina in particular tend to accumulate environmental contaminants. “For some reason they tend to graze on junk,” he says. Leave a fiberglass tape on the ocean floor overnight, for example, and they’ll chew through it by morning. “They’ll be accumulating a lot of the metals and the plastics, and then of course they get eaten by snapper. That will be an issue in the debris field area for quite some time.”

Battershill’s colleague Phil Ross sympathises—seafood from the reef wouldn’t be his first choice. “Nothing has gone even close to a level where it would be considered dangerous, and it’s probably safe, but if I wanted to eat urchins I could collect them somewhere there hasn’t been a shipwreck,” he says. “It’s not because I think it’s dangerous, but there’s always uncertainty about contaminants in people. Why expose yourself to it if you don’t need to?”

Even if the levels of contaminants in seafood are considered to be safe, for tangata whenua, serving food of pristine quality at a hui or tangi is a matter of pride. “If there’s a hint that it’s blemished in any way then their mana is decreased,” says Battershill. “It might be fine in terms of the parts-per-million concentration of the metals in the kina gonads and flesh, but you know in the back of your mind that this has come from an area that has been compromised.”

The question is whether removing the wreck will change the level of contamination in sediments and biota, and at this point, consensus is that it won’t. If the skeleton of the ship is taken away, Ōtāiti won’t revert more quickly to the state it was in when the Te Arawa waka rested there or the Akuhatas’ ancestors fished. The contaminants have already been dispersed, and they aren’t things that a salvage crew, with all their 200-tonne cranes and electromagnets and grab arms, can gather up.

[Chapter Break]

After the last day of hearings in Tauranga, I sat on the beach at the Mount and watched container ships passing each other through the haze of blue on the horizon. Soon, these will increase in size—the Port of Tauranga has obtained resource consent to dredge the harbour in order to accommodate ships up to 347 metres in length, a significant step up from the Rena’s 236 metres.

I’ve heard submissions from scientists, tangata whenua, salvors and lawyers, but I can’t help feeling there’s been something missing from this process: a representative of New Zealand overseeing it all, meeting with communities and hearing their concerns in the same way that Zacharatos has been doing for the past four years.

How much mamae could have been spared if, for example, Daina had been advised on how to meet with tangata whenua, and who the correct representatives were? If Chris Battershill had been able to continue lacing Western science with mātauranga Māori—traditional knowledge—in the environmental monitoring programme? If there was a Crown figure identifying potential environmental issues in advance and commissioning research in order to investigate them?

Tauranga iwi Ngāti Ranginui, which initially opposed resource consent, chose to settle with Daina in May in order to avoid entering into arguments about whakapapa and kaitiakitanga within the hearing, wishing to avoid a contest of who had the strongest connection to Ōtāiti. Though the iwi met frequently with Zacharatos to discuss concerns, they did not enjoy the same relationship with the regional council or the Crown. “One of the lessons New Zealand could learn from this is how not to go about a major environmental disaster,” says Stephanie O’Sullivan, Ngāti Ranginui’s chief executive. “The lack of process, the lack of care and the lack of direction from the Crown has led to the community becoming divided. We talk quite a lot about the need to learn from this, and the need to implement more effective processes that strengthen rather than divide communities.”

Meanwhile, Phil Ross believes science could have better informed the clean-up process. On one dive, he noticed grinding media—small metal balls—that were rolling around on the reef bed in stormy weather, crushing what was in their path. The salvors, he says, didn’t realise how much damage the smaller, mobile pieces of debris caused to the reef—their focus was on the larger pieces of the puzzle. It was up to Ross to convince TMC Marine that this needed addressing.

Ross is conscious of the fact that for the past few years, he’s been in the employ of Daina after the regional council decided that the shipping company, rather than local government, ought to pay for environmental monitoring. It’s not the best look, he concedes, but there was no other option, and he’s tried to be the environmental advocate who has been missing from the process. “To the shipping company’s credit they have allowed us to do research and monitoring, which isn’t necessarily in their best interests in terms of the potential to uncover problems, but that shouldn’t have been an issue,” he says.

New Zealand got off lightly with the Rena, says Chris Battershill. While the oil looked disastrous, he says, the fact that it was swept onto sandy shores quickly meant that it could be collected quickly. “Six months later, there was negligible effect on the organisms around the bay area.”

Moreover, the ship wasn’t at capacity—rather, it was more than a third empty, with 477 of its 1368 containers bearing no cargo, and only 32 carrying dangerous goods. If consent is granted to abandon the wreck, it will come with a host of conditions: at least a decade of environmental monitoring, and an obligation to clean up any pockets of copper or TBT that are uncovered.

Battershill has played a central role in the $2.4 million government-funded Rena Recovery Plan, from the week of the grounding until late 2014. Now, his team at the University of Waikato will be seeking to plug a gap in the world’s understanding of environmental disasters: what happens when a cocktail of contaminants is stirred together in a marine ecosystem. “There’s just no information about the combined eco-toxicity of metals and hydrocarbons, and there’s no information about how they degrade over time,” he says. “The study will generate information of substantial use to all people confronted with maritime disasters, so you can address those questions that people ask immediately, ‘What’s the impact going to be? How will it affect people?’”

It appears that the Rena is about to embark on a new voyage, taking on the central role in a large and enduring science experiment—a second life that promises to be much more beneficial to the marine environment than her first.