Part I: A bid to incinerate tonnes of waste is billed as better than burying it, but doubts about highly toxic fallout worry neighbours including a nearby dairy factory.
We make too much rubbish. Last year, 566kg per person went to municipal landfills. So, some say, burn it. Waste-to-energy incineration generates heat and electricity, too. It’s done in many countries, and an application for consent to build such an incinerator in Te Awamutu will soon be considered. If approved, it would be New Zealand’s first – and it could ease the way for others.
Attempts to build such incinerators have popped up in several small towns in recent years, but none have eventuated. The most recent demise was in Canterbury’s Waimate district where one was accepted into the fast-track regime. The company lost its agreement to buy land, voiding its fast-track inclusion. It had faced enormous local opposition.
Te Awamutu locals feel the same, the mayor writing, “It is hard to overestimate the strength of feeling that exists in the community against the proposed waste-to-energy plant.” Waikato-Tainui oppose it. Key concerns include air and water pollution, residual ash, climate effects and less incentive to reduce waste.
A legal battle is therefore under way. On one side is the company applying for resource consent, Global Contracting Solutions (GCS), owned by metal recyclers Global Metal Solutions. It’s armed with a King’s Counsel, a barrister and 21 expert witnesses.
In opposition are the site’s two immediate neighbours, a Fonterra factory and a racecourse. They’re joined by the Zero Waste Network, the Environmental Defence Society, the Ministry of Education (representing schools within 600m) and Waipā District Council.
The face-off was due to begin in Hamilton this week before a board of inquiry ordered by Environment Minister Penny Simmonds, who deemed it a matter of national interest. Local councils requested the decision be removed from them. Three commissioners will decide whether the incinerator can go ahead, their verdict likely to influence the success of other hopeful waste-to-energy operators. Board of inquiry decisions can be appealed only on points of law.
Clear the air
GCS proposes to incinerate about 150,000 tonnes a year of municipal waste, plastic, tyres and “floc” – shredded metal recycling leftovers from wrecked vehicles and whiteware, including upholstery, plastic and rubber. Floc can contain serious pollutants (see “Floc with nowhere to go?”, below). It’s unclear where the municipal waste would come from.
Modern waste-to-energy incinerators have filters and scrubbers to capture most pollution. When all runs smoothly, they do that. But expert witnesses are clashing over how effective the pollution controls would be, as revealed in their written evidence. The controls are imperfect: sulphur dioxide, nitrogen dioxide, mercury, dioxins and particulates, at least, will be discharged. These are colourless and largely odourless, and there’s abundant evidence they can cause illness and shorten lives.
But they are already present in our air, and GCS need only prove the plant would discharge less than New Zealand air quality rules allow. The Parliamentary Commissioner for the Environment has repeatedly said those standards are woefully outdated and not in line with World Health Organisation guidelines.
Pollutant levels from incinerators depend greatly on what’s burnt, and GCS has wavered on this in its evidence, from 10% floc to 23% and back to 10%. Regardless, GCS’s air-quality expert considered only the default emission maximums provided by the plant’s manufacturer.
Dioxins are probably the most concerning pollutants. These can be created by burning chlorine-containing material, such as floc and some plastics, by bleaching with chlorine and by smelting. They’re a “code red” chemical group, classed as persistent organic pollutants and carcinogenic with no safe level.
Even modern incinerators release them. Research focuses on the challenge of predicting how emissions change with the burn temperature and type of waste. A 2023 Chinese study states: “According to the most recent research, even with advanced contemporary air pollution control devices, dioxin emissions from municipal solid waste incineration facilities continue to fluctuate widely and may even exceed emission limits.”
Some studies report dioxins are not higher in soil or blood samples taken near incinerators, but others report the opposite. Many agencies, including our Environmental Protection Authority, set a low dioxins level that’s considered tolerable.
They’re also hard to measure. Some air contaminants can be measured continuously, but dioxin results take six weeks, as do results for metals, another discharge nobody wants to inhale. GCS proposes testing for all these just yearly, creating a retrospective snapshot that cannot reveal ups and downs (the most polluting phase would be an unplanned shutdown).
Europe has “best available technology” limits for contaminants, which GCS mostly plans to adopt, but it wants higher allowable limits for others, including dioxins. That’s during normal operation, not when pollution escalates during blips in combustion.
Dioxins are a ‘code red’ chemical classed as carcinogenic with no safe level.
It’s possible to burn floc and plastic without creating dioxins and even to destroy them, but the temperature needs to be much hotter. GCS’s 850oC plant is acceptable only if the fuel contains at most 1% chlorine, a content it now proposes to meet. It would check that by testing representative waste samples – no small challenge when incinerating hundreds of tonnes daily.
If pollutants are too high, who takes action? The Waikato Regional Council would be responsible. Barry Barton, professor of environmental law at the University of Waikato, says mistakes do happen when operating complex machinery. He suspects monitoring and enforcing consent conditions would be burdensome for regional councils (see “Hardly compliant”, below). “Most do a good job most of the time, but we have cases where councils have been slow to take action.”
Councils currently have clumsy mechanisms to deal with things like pollution events, says Barton, who co-authored a New Zealand Law Journal paper on waste-to-energy incinerators. They can issue an abatement notice to cease operation, but that’s often legally challenged, so incineration would continue until a court resolved the matter.
Long-time contaminated site consultant Dave Bull is disillusioned with people’s grasp of how consents work. “People think, ‘I’ve got consent to do my project. Now I’ll do my project the way I want to.’ Councils tell them, ‘No, you have to do it the way you said you would.’ They say, ‘What?’ It just doesn’t compute for us. New Zealanders don’t want to plan in advance; we want to start the project now and sort the details out later.”
Hashed ash maths
Bull, of Hail Environmental, says it’s possible to clean up air emissions. “But what I want to know is where all that ash is going to go – tonnes and tonnes of ash. The ash may very well be more toxic than what you put in in the first place.”
The regional council wonders, too, and it asked for evidence that a landfill operator would accept it, for an ash disposal plan and for details of the likely contaminants. GCS gave no clear answers, saying the ash destination shouldn’t affect whether consents are granted.
A small proportion of the ash will be fly ash, a known carrier of heavy metals, acids and dioxins. The company provided a letter stating fly ash is not hazardous waste in New Zealand. With enough money, energy and the right kit, fly ash can be treated to stabilise the hazardous contaminants, but that’s not proposed.
How much ash will there be? That matters because it will have to be stored and trucked away somewhere (locals are concerned about truck movements). GCS plans to burn 400 tonnes of waste daily (another document said 600 tonnes) after processing it to extract recyclables. Its own experts say a fifth to a third of incinerated rubbish’s weight remains as ash. That makes 80 to 180 tonnes of ash, yet GCS expects 23 tonnes.
It now says there’s “an expression of interest to take all available suitable ash outputs” for concrete. That greatly surprised Tim Kleier, sustainability and policy director for Concrete NZ, when the Listener told him. Fly ash is used to replace some cement, he says. But “the standard in New Zealand is very specific that we can only use fly ash from coal combustion and not fly ash from, for example, waste incineration.”
He welcomes innovations to reduce the emissions from concrete making, but says any change would require new standards plus analysis and research to check how it influences the concrete’s characteristics.
The Listener also approached Tyrewise, the mandated stewardship programme that manages all end-of-life tyres other than old tyre stores. It hadn’t heard of GCS’s plans to incinerate some 80 tonnes of tyres daily, a large proportion of what Tyrewise collects.
Another material likely to be contaminated is water, from washing the recycling area and plant. In Europe, this water is often treated on site, with variable success. “You can treat water for just about anything, if you’re prepared to spend the money running it through this filter and that,” says contaminated land specialist Bull. Still, filters and their trapped toxins need disposal.
GCS has been unclear about its wash water contaminants, despite the regional council asking twice about that and for evidence a managed waste facility will accept it. Luckily, someone is interested: GCS’s owners, Global Metal Solutions, for firefighting and washdown at its metal recycling facilities (it’s had three fires in the past five years). It’s unclear what happens to runoff from those sites.
Is landfill better?
Another disagreement is whether incinerators or landfills generate more planet-heating emissions. A council-commissioned report concluded that if most food scraps and garden waste are separated out, waste-to-energy incinerators produce much more greenhouse gas. That’s because burning plastic releases its carbon, whereas landfills store it.
GCS’s experts calculate the incinerator would produce less greenhouse gas than landfills, which release methane when organic materials rot. Modern landfills capture methane, but not all of it. However, GCS proposes to remove food and green waste from municipal waste before it’s burnt, so they will decay somewhere.
The incinerator would produce a modest amount of electricity for a power plant: about 15MW, according to the company, enough to power about 14,000 homes. So could 12 wind turbines, costing much less than the $300 million plant.
What won’t be useful is the waste heat that incinerators overseas pipe to nearby homes or industries. That’s not proposed for Te Awamutu. The Fonterra factory next door could potentially use it, but Fonterra opposes the incinerator for fear of milk powder contamination.
Fonterra points to international vigilance for dioxins, which accumulate in dairy and meat fat. China requires infant formula factories to identify potential contamination sources within a 1km radius and state their risk mitigation measures. Fonterra’s evidence opposing the GCS proposal says there’s a risk overseas food regulators may “decline the renewal of the Te Awamutu Dairy Factory’s registrations, due to the significant risks imposed by the [facility]”. European food regulations impose “part-per-trillion” dioxin limits, says Fonterra. Overseas regulators also set tight rules on per- and polyfluoroalkyl substances (PFAS), “forever chemicals” that would inevitably enter an incinerator but are unlikely to be destroyed by it.
The other large neighbour is the Waipā racecourse. It’s zoned for housing, and Waikato Thoroughbred Racing wants to sell it. It’s concerned the incinerator would deter house buyers.
GCS did not respond to the Listener’s questions on its application.
Feeding the beast
Heads are also butting over whether incineration helps or hinders the shift to making less waste (Go here to read Tackle the source). Tonnages going to landfill can taper over time, but incinerators need ongoing supplies. In the UK, some councils are locked into long contracts to supply incinerators. The UK has about 60 waste-to-energy incinerators, mostly in poorer areas, with about 40 more planned. Opposition is huge. Incinerators are the cheapest disposal option, but that may change when they enter the UK’s emissions trading scheme.
Any incinerator here would automatically be in our ETS, but waste-to-energy operations are exempt from the waste disposal levy that landfills pay. The government recently proposed lifting that blanket exemption, meaning incinerators could be levied.
Barry Barton agrees that makes sense for incinerators, but not for clean disposal of uniform waste streams: wood residues fuelling sawmill furnaces, tyres replacing coal in a cement kiln, Reporoa’s food waste digestor making biogas.
The board of inquiry has an unenviable task, Barton believes. He says the Resource Management Act provides little direct guidance for high-level evaluation of waste-to-energy proposals – such as how to regulate them, what can be incinerated and whether they align with the government’s waste strategy. He says updated regulations to clarify such things are sorely needed.
Barton himself changed his mind on incineration. “When I first started thinking about these things, I thought waste-to-energy was a good idea, but the more I read, especially about the air-quality issues, the more I realised I had to reconsider. It’s paradoxical to think that environmentally, the best thing is to bury it in a modern, well-run landfill.”
Floc with nowhere to go?
Floc currently goes to landfill. But that may have to stop because some non-metal vehicle parts contain persistent organic pollutants (Pops) such as fire retardants and the forever chemicals known as PFAS. Pops are toxic, do not biodegrade, build up in human and animal tissue, and pass through the food chain.
Rules for disposing of Pop-containing items have been tightened under the Basel Convention on hazardous waste. Corresponding rules were proposed here by our Environmental Protection Agency, which, if passed, will prohibit Pop-containing items from being used as fuel to generate energy.
That applies only if Pops are present at high enough levels, and it’s unclear whether non-metal vehicle parts exceed that threshold. The Environmental Protection Agency says it understands that’s unlikely. But if they do, floc could no longer go to even highly engineered class 1 landfills, but unshredded vehicle parts could.
Hardly compliant
All resource consents have conditions, but will they be kept to – and enforced? Consider a consent the Bay of Plenty Regional Council issued last year to Rainbow Mountain Renewable Energy for a trial using pyrolysis (high temperature decomposition) to dispose of floc and plastic at a plant at Waimangu, near Rotorua. The trial tested how the plant and its air discharge responded to various fuel loads over six months.
The council’s consents planner recommended limits on air contaminants and regular testing to “ensure the potential effects on the environment and human health are avoided”. If pollution exceeded limits, the firm must “complete the trial in progress and then cease operation … until the following steps have been taken …” On that basis, local residents weren’t told.
The council then issued conditions requiring only three rounds of testing. It received no results until the trial was finished. The company’s environmental consultant, Industrial Compliance Solutions Ltd, withheld for months a result revealing carbon monoxide three times over the limit. With that result and with some metals over their limits, it reported “full compliance with the emission limits”.
Industrial Compliance ran tests across just one day instead of three. It didn’t test for volatile organic compounds, which can cause odour and health effects. (It attributes the lack of testing to a plant breakdown for three of the six months.) Neighbours complained of rubber and chemical smells.
The council’s audit of compliance with conditions ignored the missing tests. It rated the consent as moderately non-compliant because of delayed results. There was no enforcement action.
When the company recently applied for a longer consent, the planner asked where the missing information was and rejected the application.