A tale of two valleys: Latrobe and Hunter regions both have coal stations, but one has far worse mercury pollution

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Larissa Schneider, Australian National University; Anna Lintern, Monash University; Cameron Holley, UNSW; Darren Sinclair, University of Canberra; Neil Rose, UCL; Ruoyu Sun, and Simon Haberle, Australian National UniversityWe know coal-fired power stations can generate high levels of carbon dioxide, but did you know they can be a major source of mercury emissions as well?

Our new research compared the level of mercury pollution in the Hunter Valley in New South Wales and the Latrobe Valley in Victoria.

And we found power stations in the Latrobe Valley emit around 10 times more mercury than power stations in the Hunter Valley. Indeed, the mercury level in the Latrobe Valley environment is 14 times higher than what’s typically natural for the region.

So why is there such a stark difference between states? Well, it has a lot to do with regulations.

Following a NSW requirement for power stations to install pollution control technology, mercury levels in the environment dropped. In Victoria, on the other hand, coal-fired power stations continue to operate without some of the air pollution controls NSW and other developed countries have mandated.

To minimise the safety risks that come with excessive mercury pollution, coal-fired power stations in all Australian jurisdictions should adopt the best available technologies to reduce mercury emissions.

A dangerous neurotoxin

Mercury is a neurotoxin, which means it can damage the nervous system, brain and other organs when a person or animal is exposed to unsafe levels.

Coal naturally contains mercury. So when power stations burn coal, mercury is released to the atmosphere and is then deposited back onto the Earth’s surface. When a high level of mercury ends up in bodies of water, such as lakes and rivers, it can be transferred to fish and other aquatic organisms, exposing people and larger animals to mercury that feed on these fish.

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Mercury does not readily degrade or leave aquatic environments such as lakes and rivers. It’s a persistent toxic element — once present in water, it’s there to stay.

The amount of mercury emitted depends on the type of coal burnt (black or brown) and the type of pollution control devices the power stations use.

The Latrobe Valley stations in Victoria burn brown coal, which has more mercury than the black coal typically found in NSW. Despite this, Victorian regulations have historically not placed specific limits on mercury emissions.

In contrast, NSW power plants are required to use “bag filters”, a technology that’s used to trap mercury (and other) particles before they enter the atmosphere.

While bag filters alone fall short of the world’s best practices, they can still be effective. In fact, after bag filters were retrofitted to Hunter Valley’s Liddell power station in the early 1990s, mercury deposition in the surrounding environment halved.

Mercury deposited in sediments of Lake Glenbawn (left) in the Hunter Valley and Traralgon Railway Reservoir (right) in the Latrobe Valley.

The best available technology to control mercury emissions from coal-fired power plants is a combination of “wet flue-gas desulfurization” (which removes mercury in its gaseous form) and bag filters (which removes mercury bound to particles).

This is what’s been adopted across North America and parts of Europe. It not only filters out mercury, but also removes sulphur dioxide, nitrogen oxides and other toxic air compounds.

Using lake sediments to see into the past

Lake sediments can capture mercury deposited from the atmosphere and from surrounding areas. Sediments that contain this mercury accumulate at the bottom of lakes over time — the deeper the sediment, the further back in time we can analyse.

We took sediment samples from lakes in the Latrobe and Hunter valleys, and dated them back to 1940 to get a historical record of mercury deposition.

This information can help us understand how much naturally occurring mercury there was before coal-fired power stations were built, and therefore show us the impact of burning coal.

Lake Narracan: one of the lakes we sampled sediments from, near a coal-fired power station in Latrobe Valley.
Larissa Schneider, Author provided

From these records, we found the adoption of bag filters in the Hunter Valley corresponded with mercury depositions declining in NSW from the 1990s.

In contrast, in Victoria, where there’s been no such requirement, mercury emissions and depositions have continued to increase since Hazelwood power station was completed in 1971.

What do we do about it?

In March, the Victorian government announced changes to the regulatory licence conditions for brown coal-fired power stations. Although mercury emissions allowances have been included for the first time, they’re arguably still too high, and there’s no requirement to install specific pollution control technologies.

There’s a risk this approach won’t reduce mercury emissions from existing levels. Victoria should instead consider more ambitious regulations that encourage the adoption of best practice technology to help protect local communities and the environment.

Loy Yang power station, Victoria’s largest, burns brown coal which contains more mercury.
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Another vital step toward protecting human health and the environment from mercury is for the federal government to ratify the Minamata Convention on Mercury, an international treaty to protect human health and the environment from mercury.

Despite signing the convention in 2013, the Australian government is yet to ratify it, which is required to make it legally binding in Australia.

Ratifying the convention will oblige state and federal governments to develop and implement a strategy to reduce mercury emissions, including from coal-fired power stations across Australia. And this strategy should include rolling out effective technologies — our research shows it can make a big difference.

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The authors acknowledge Lauri Myllyvirta from the Centre for Research on Energy and Clean Air for her contributions to this article.

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Larissa Schneider, DECRA fellow, Australian National University; Anna Lintern, Lecturer, Monash University; Cameron Holley, Professor, UNSW; Darren Sinclair, Professor, University of Canberra; Neil Rose, Professor of Environmental Pollution and Palaeolimnology, UCL; Ruoyu Sun, Associate Professor, and Simon Haberle, Professor, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Research suggests Tony Abbott’s climate views are welcome in the Hunter Valley

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Vanessa Bowden, University of Newcastle

Former Prime Minister Tony Abbott this week drew renewed attention to himself with a speech to the Global Warming Policy Foundation, a London-based climate sceptic group, in which he voiced a range of doubts about climate science and policy, and claimed that climate change is “probably doing good”.

The comments might come as no surprise to those familiar with his views. But what’s arguably more surprising is the prevalence of similar opinions among some Australian business leaders.

My research, published this week in the journal Environmental Sociology, features interviews with business leaders in the Hunter Valley of New South Wales – a major coal-producing hub.

It reveals that Abbott’s doubts about the veracity of climate science and its forecast impacts, and his scathing dismissal of those concerned about climate change, have a long history of support among the Hunter Valley’s business leaders.

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Carried out in the lead-up to the implementation of the Gillard Labor government’s price on carbon in 2011, my research sought to understand business leaders’ attitudes to government policies and to climate change more broadly.

I approached 50 chief executives of organisations operating in the Hunter Region, of whom 31 agreed to participate (or had a senior staff member take up the opportunity).

They were asked questions about their views on climate change, how and whether their organisation was responding to the issue, and what they thought about the various political parties’ policies in response to it.

Perhaps not surprisingly, participants’ overwhelming concern was that the economy might decline as a result of climate policies such as pricing carbon.

While some were concerned about climate change, there was almost unanimous opposition to carbon pricing. Given the politics of the time, this too is unremarkable, particularly in light of the success Abbott enjoyed at the 2013 election after pledging to scrap the policy.

What was surprising, however, was the pervasive scepticism among participants about the science of climate change. This is especially the case given that many people now view the debate over whether climate change is happening – and whether it is caused by human activity – as being over.

Moreover, many participants believed that climate scientists were motivated by financial rewards in arguing that climate change is a serious concern.

These beliefs were voiced not only by those in industries like coal, aluminium, and shipping – but echoed by participants from other industries, revealing a deep scepticism of both the discipline and the science of climate change itself.

It is noteworthy that the research was focused on the Hunter Valley and Newcastle, home to the world’s biggest coal port.

Participants also held intensely antagonistic views in relation to the environment movement and the Australian Greens, believing their views were quasi-religious and that they too were self-interested and unrealistic in wanting to tackle climate change.

Striking views

In some ways the extremity of these comments was striking. Although prominent in writings by conservative columnists at the time, the broader debate was much more focused on jobs and the economy.

A small minority of participants did support some type of mechanism to limit greenhouse emissions, and were concerned about the environment.

But more broadly, my research showed that the Hunter Region’s business leaders – whether or not they were directly involved in coal – had taken on board many of the arguments promulgated by the industry in its ultimately successful campaign against carbon pricing in Australia.

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These dynamics may have changed a little in recent times, with companies such as AGL and BHP shifting away from coal.

The overall dynamics of the climate politics, however – as revealed in the current stalemate over responding to the Finkel Review – remains out of step with what the climate science is telling us. As, of course, do Abbott’s comments.

Abbott’s London speech was interpreted as incendiary, and earned him a sharp rebuke from government colleagues. But when we look at the places where his message might be received more favourably, it becomes apparent there are still pockets of the country where he might expect to find a plentiful and powerful audience.

Vanessa Bowden, Associate Lecture in Social Enquiry, University of Newcastle

This article was originally published on The Conversation. Read the original article.

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