ABOVE: Alice Matthews takes a look at the debate over drilling for oil in the Great Australian Bight.

Norwegian company Equinor wants to drill a 2.2 kilometre 'exploration well' roughly 400 kilometres south of the South Australian coast. The federal regulator NOPSEMA (the National Offshore Petroleum Safety and Environmental Management Authority) has been reviewing the company's emergency response and 'clean up' strategy.

As part of the strategy, the company plans to use a chemical 'dispersant' - Corexit 9500 - to clean up in the event of a spill. It's currently banned in parts of Europe.

A 'dispersant' chemical breaks up oil slicks into small droplets, which makes the overall biodegradation process easier. The substance is sprayed onto spills from a plane.

AAP

Equinor's 'Environment Plan' is publicly available online. Corexit 9500 is mentioned 15 times.

"The oil spill response may involve different commercial chemical dispersants, depending on how long the response runs for, and each dispersant may have different biodegradation characteristics," the report reads.

The company says it undertook a 'net environment benefit analysis' to assess the merits of using chemicals like Corexit 9500.

Use of sub-sea dispersant application... is an accepted strategy that is considered appropriate for this project and an important response tool by response agencies worldwide.

This week, NOPSEMA issued a notice to Equinor, asking the company to resubmit their proposal.

"Equinor must provide NOPSEMA with further information about matters relating to consultation, source control, oil spill risk, and matters protected under Part 3 of the Environment Protection and Biodiversity Conservation Act 1999."

The announcement follows the release of a report from Greenpeace slamming the strategy.

Here's why Greenpeace is so worried about Corexit 9500:

Greenpeace alleges that using dispersants like Corexit 9500 will increase the toxic effects of an oil spill - as it's exposing the environment to more chemicals.

"Dispersants are little more than marketing tools that oil companies use to give a false impression that they are somehow reversing the environmental damage their oil spills have caused, which is simply impossible," said report co-author, Dr Nikola Casule.

Corexit was put to the test in real-world conditions and failed spectacularly.

That 'test'? Deepwater Horizon, the largest marine oil spill in history.

In April 2010, millions of barrels of oil gushed into the Gulf of Mexico after a blowout at an offshore oil rig owned by BP.

The oil leaked for 86 days before it was finally capped on July 15. In the clean up, 6.9 million litres of dispersants were sprayed on the spill and injected into the well itself. More than 1.8 million litres of Corexit 9500 was used.

Greenpeace warns that studies undertaken in the years following Deepwater Horizon have shown that the chemical is harmful - and possibly deadly - to a "wide range of marine life, including whales, fish, oysters, coral, crabs, and the tiny zooplankton, that are the foundation of the marine food chain."

Nothing could be worse for the Great Australian Bight than a devastating oil spill, right? Wrong. @Equinor 's proposed solution - a banned toxic chemical - could make a catastrophic situation even worse.



Read our exclusive new report: https://t.co/6LoQIP694A #fightforthebight pic.twitter.com/g1avmBBwAz — Greenpeace Aus Pac (@GreenpeaceAP) November 6, 2019

In 2018, the Canadian government quietly approved the use of Corexit 9500 in the event of a spill off the coast of British Columbia.

However, the report from Greenpeace noted that Corexit 9500 is currently banned outright in Sweden and offshore in the UK, due to the damaging effects.

Equinor's plan quotes research from as early as 1995, through to 2017, to support the use of the chemical. In particular, it appears to seek to dispel concerns made by Greenpeace. For example:

"The US Environmental Protection Agency (2010) compared the acute effects of eight dispersants on two species and found that Corexit 9500 was slightly toxic to the crustacean, but "practically non-toxic" to the fish."

AAP

Equinor's Australia country manager Jone Stangeland told The Feed where dispersants are required, the company will opt for chemicals that are already approved.

In a statement, Stangeland reiterated that Corexit 9500 would only be used if there were 'shortfalls in the supply chain' of other, acceptable dispersants.

Any decision to use transitionally approved dispersants will be made in conjunction with government agency advisors.

However Greenpeace, in its own report, slammed Equinor's environmental assessment as 'deficient', saying:

"Both the regulator and the community are in the dark as to the scale of the environmental threat."

Reuters

So how can Equinor get away with using a ‘banned’ chemical?

A register of all 'acceptable' dispersant chemicals and their classifications is available on the Australian Maritime Safety Authority (AMSA) website.

Two of the three chemicals Equinor has listed in their report - Corexit 9500 and Ardrox 6120 - are not currently listed as 'acceptable'. Greenpeace alleges Corexit 9500 has not been on the 'acceptable' list since 2012.

Instead both chemicals fall under the 'transitional acceptance' listing. This could allow Equinor to use the substance in a clean up.

Transitional acceptance, as defined by AMSA, means that companies like the Norwegian oil driller are permitted to use stockpiles that have been accrued under an earlier 'acceptance' ruling.

Basically, that means the only reason Equinor's allowed to use Corexit 9500 is because it has stockpiles of it. After they're out of the chemical they're not allowed to seek more of it.

For each chemical, AMSA outlines a list of 'Relevant Information' - anywhere from one to seven documents. Interestingly, Corexit 9500 is the only chemical to have no documents available.

Last month, NOPSEMA extended the environment plan assessment period deadline beyond the original 30 days, advising the company that it was unable to make a decision due to the complexity of the case.

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Equinor says it 'always expected' to make resubmissions to the regulator about its plans.

"Based on the industry's experience, we know NOPSEMA accepts only 10 per cent of plans on first submission," Jone Stangeland told The Feed.

In a statement, Stangeland said the company remained committed to gaining approval for the project.

We continue to engage with stakeholders and local communities regarding details of our plans.

Greenpeace has warned the company that opposition to the drilling is 'greater than ever'.

"The communities of the Bight, Traditional Owners and the thousands of people in the seafood and tourism industries whose livelihoods depend on healthy oceans will never accept oil drilling in the Bight."

Equinor says it's now focused on providing the information NOPSEMA has requested before the next deadline. It's still planning to begin drilling by late 2020.