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Dumping Abbot Point dredge spoil on land won’t save the reef

Abbot Point on the Great Barrier Reef, where dredge spoil will be dumped on land. AAP Image/Supplied by Greenpeace

Queensland Labor’s new plan to dump Abbot Point dredge spoil on land announced last week, and not at sea or in sensitive wetlands as under previous proposals, is a welcome one, but it will do little to stem the flow of damage to the Great Barrier Reef.

Meanwhile the federal government continues to make efforts to keep the Great Barrier Reef off the World Heritage In Danger list, on Monday announcing laws to ban dredging within the Great Barrier Reef Marine Park, excluding maintenance dredging at established ports.

However of the nearly 6.4 million cubic metres of spoil dumped since 2010, around 84% has been dumped outside the Marine Park but in the World Heritage Area. A ban from the World Heritage Area would be more meaningful.

Under the previous state government, the dumping of 5 million tonnes of dredge spoil in the sea for the massive expansion of the Abbot Point Coal Port was abandoned in favour of dumping 3 million tonnes on Caley Wetland, with a new suite of devastating problems.

The new government intends to continue with dredging for Abbot Point and the Galilee Basin Coal mines for which it is being built.

There are few details yet on the new dumping plan, but the site is adjacent to the sensitive Caley Wetland and still close to the sea, so will not be without problems.

The other options for port facilities at Abbot Point, such as trestles requiring little or no dredging, were dismissed as being too expensive, without a comprehensive assessment of the risks or benefits.

Similarly, options for onshore dumping further inland have not been mentioned.

Dumping dredge spoil not the only problem

Much of the focus has been on the effects of dumping the dredge spoil, but this is not the only detrimental action. The actual dredging is problematic. The sea bed is removed, along with seagrass and animals. Plumes of sediment result, causing movement of whatever is held in these port sediments, potentially poisons and elevated nutrients.

Sediment will cut light for photosynthesis of seagrasses and coral symbionts and will smother both recruit and adult corals and other benthic animals. Recent evidence has also shown a doubling of the incidence of coral disease close to dredged areas.

Recent dredging in Miami, USA has led to disease, smothering and death of the corals in the region. This is not due to dumping of dredge spoil, just dredging and in spite of assurances and protection processes in place by the proponents.

Whilst avoiding coral spawning times for dredging is admirable, there can be no period during which dredging will not adversely affect nearby corals, particularly young corals which have very slow initial growth and are particularly susceptible to sediment effects for at least the first year or two.

Coal ports will contribute toxic coal dust to the surrounding terrestrial and marine areas. There are high levels of coal dust across hundreds of kilometres of the Great Barrier Reef and at toxic levels close to Abbot Point already.

The Abbot Point Port development will result in a huge increase in shipping. Although there has been great progress in improving Great Barrier Reef shipping regulations, increasing ship numbers will increase risks such as ship groundings on reefs and resulting spills, strikes on wildlife such as turtles, whales and dugongs, and the introduction of pests through attachment to ships or in ballast water. With more ships comes an increase in noise which can negatively affect a range of marine animals.

Broken process

To manage and protect the Great Barrier Reef, the approvals process for developments within the Great Barrier Reef Marine Park needs to be overhauled, as its failure is fundamental to much of the damage caused through developments.

An Environmental Impact Statement (EIS) is required for proponents of projects of economic, social and/or environmental significance to Queensland. An EIS is an investigation of the risks and potential impacts associated with a project and is required under either local, state or federal legislature depending on the project.

Now, the proponent appoints and commissions the consultants undertaking an EIS. As the statement is not independently peer-reviewed, errors are not corrected and the problems are multiplied when the statement informs the monitoring program.

For example at Hay Point, another port on on the Great Barrier Reef, the environmental impact statement modelled the spread of the dredge plume and divided sites into “impact” and “no impact”. However the dredge moved further than modelled, and in the event corals were affected at both sites.

When monitors went to assess the impact of dredging on the reef, they found diseased and damaged corals at impact and no impact sites. By comparing the two, they concluded that there had been no impact of dredging, as all sites were badly affected.

Another example of this broken system is in the EIS for Abbot Point.

This showed toxic polycyclic aromatic hydrocarbon levels (or PAH – found in coal dust) in sediments in the dredge area below Australian and New Zealand Environment Conservation Council guidelines. But the analysis used in the environmental impact statement was not suitable to assessing hydrocarbons from coal activities, so couldn’t accurately predict the risk.

The modelling for the Abbot Point environmental impact statement also predicted that the dredge would stay close to shore. But it has been shown that sediment plumes readily reach the outer reefs, and re-examination of sediments showed that PAH from coal dust levels in sediments exceeded 2013 guidelines.

The approval process for the Caley Wetlands dredge disposal was particularly regrettable. There was no environmental impact statement and the minimum legal period of 10 days was allowed for comment just before Christmas. It raises concerns about the precedent that may have been set for future developments.

Changing approvals

Both the Australian government and the previous Queensland government desire a reduction in environmental regulations, including removal of the federal level of approvals. This federal capacity to veto has been used in many crucial environmental decisions in recent history.

I recommend:

  1. Consultants need to be selected and paid by an independent body such as Great Barrier Reed Marine Park Authority (with funding from project developers)

  2. The environmental impact statement design and completed work needs to be peer-reviewed by independent scientists

  3. The environmental impact statement needs to be made available to the general public straight away without the impediment of confidentiality clauses which often prevent information reaching the public.

The greatest challenge facing the Great Barrier Reef is climate change, with ramifications including coral bleaching, sea level rise and reductions in reef growth rates. There has been substantial reef degradation from climate change already.

If we want to keep the Great Barrier Reef in a good state, a broad range of policies should be urgently put in place to reduce Australia’s record high per-capita carbon emissions to a much lower level.

Carbon dioxide emissions from the Galilee compared to other nations. Data sourced from IEA

Burning coal from all of the mines proposed for the Galilee Basin would result in an incredible increase in emissions. It has been estimated that it would be 705 million tonnes of CO2 per year compared to Australia’s total 402 million tonnes in 2010. In 2012, this was more than the annual emissions of any country excepting the top 6 emitting countries. Obviously this will dwarf any reductions planned by our current governments.

To increase the resilience of the reef, to maximise its chances with climate change, we must reduce further stresses to the Great Barrier Reef such as those caused by port developments on the coastline.

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