Australia operates four research stations in Antarctica and Sub-Antarctica that are permanently manned. Over the years, quite some legacy waste has accumulated at the stations, which has already contaminated soil. Now, the Australian Antarctic Program is planning its largest-ever environmental cleanup in Antarctica with the removal of waste and contaminants.
The oldest Australian station is the one on the subantarctic Macquarie Island which was established in 1911. It was not until several decades later, in 1954, that Australia established its first station on the Antarctic continent, “Mawson”. Three years later, the “Davis” station followed, and in 1969, “Casey.” All four stations depend on fossil fuels for their operation, as almost all other research stations in Antarctica do. Over the decades, it happened that fuel was spilled during storage, transport or use.
To assess the extent, risks and impacts of legacy and soil contamination, scientists equipped with drones, ice drills and analytical equipment will travel to all Australian stations, including the former Wilkes Station, in the coming years. According to Australian Antarctic Division (AAD) senior environmental toxicologist Dr. Catherine King, the program aims to better understand the environment at risk, prioritize remediation efforts, and identify what tools and technologies will ultimately be needed for the task.
“Over the next five years, contaminated sites across Australia’s Antarctic Territory will be examined, including the former Wilkes station,” Dr. King said. “This is about understanding what is there and the effect it’s having on the local Antarctic environment. Then, based on environmental risk, prioritising which sites need to be addressed first, all the while making sure we don’t make the situation worse.”
Samples and data collected during fieldwork will be analyzed by AAD in Tasmania in collaboration with Australian and international research partners. These additional efforts complement those already underway at Casey Station.
For 11 years now, the contaminated soil at Casey Station has been remediated. The Australian team of scientists is aided by Antarctic bacteria that feed on spilled fuel. To do this, the team created mounds of soil, known as “biopiles,” which have to be turned over from time to time. However, the process takes a long time, because the bacteria are active only in the summer.
“This season one of our major tasks is to excavate a former fuel storage site. In order to do that we’ll have to dig up the soil, treat the groundwater and we’ll also be sampling the soil and running a number of small experiments. The soil from the excavations will be added to the biopile,” says Dr. Rebecca McWatters, field project leader at Casey.
Kasey Williams, expedition scientist, adds, “We’re relying on these naturally occurring bugs in the soil. They do their magic and we’re just here to enhance those natural processes.”
In the course of the remediation work, polluted meltwater is also produced, which requires special treatment. For this purpose, expedition scientist Gavin Allen operates a small wastewater treatment plant near the biopile to ensure that contaminated water does not flow back into the environment.
“That meltwater is captured and put through the water treatment plant and the hydrocarbons are separated from the water. Hydrocarbon is essentially diesel and there is quite a lot of it on the site,” Allen says.
The project is expected to be completed in the next three years, when all four sites around the station have been remediated. In the long term, the plan is to investigate which other sites in Antarctica might be considered, as Tim Spedding, head of the remediation project, explains. “We continue to develop, look for and apply new techniques to assess contamination in polar environments,” Spedding said. “Our findings and experience will inform clean-up across Antarctica by all nations, whether through setting the standard of environmental stewardship by Australia or directly supporting clean-up activities by other nations.”
Julia Hager, PolarJournal
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