This week at Casey: 16 November 2012

What’s that old proverb? “One person’s trash is another person’s treasure.”

That was heard in murmurs this week down by the waste treatment building as the old scaffold storage racks were being dismantled. Everyone on site that had a backyard shed could envisage storing some of the contents there. A little slice of history was unveiled as materials that had been supplied for various building projects, such as the accommodation building (“Red Shed”) 34 years ago, were revealed. Surplus materials were also stored there in case of emergency reminding us of every hoarder’s internal mantra that “it will come handy one day”.

Everything from steel beams to site-services pipe work, scaffold pipe to PVC conduit with wooden crates were discovered, all bearing shipping labels from the grand rebuilding program of the 80s and 90s by Australian Construction Services. It is hard to imagine that every piece of these comfortable buildings that we work, rest and play in arrived here in a building crates. Rest assured that anything useful will find another home and the remainder will be returned to Australia for recycling.

Kenny Smith 

The remediation team is back at Casey this season working on many different projects. The early season team consists of six members brought in from around the world and different universities.

One of the main projects for the team this season is a continuation of the remediation of the 1999 fuel spill at the main powerhouse fuel tank. The clean-up approach required a low-cost technique suitable for Antarctic conditions and was the first major instance in Antarctica of a comprehensive remediation strategy. Key aspects of this strategy involve managing a contaminated site using Permeable Reactive Barriers (PRBs) and biopiles. The PRBs, built in 2005 and 2011, are positioned in the ground and intercept the fuel (hydrocarbon) plumes moving from the source through the soil. It is then directed to the bioremediation treatment zone of the barrier. The PRB is equipped with sensors and sampling ports to log data, sample groundwater and investigate the performance of the barrier treatment material at removing hydrocarbons from the groundwater.

Over the past two seasons, excavation of contaminated soil at this spill site was completed and all soil was placed in the biopiles. The biopiles are contained treatment cells employing engineered liner systems to prevent migration of contaminants out of the cells to the surrounding environment. Within the cells, both bioremediation (where natural microorganisms in soil degrade hydrocarbons) and aeration of the soil occur.

The remediation team arrived back to the site in early November to discover that both PRB and biopiles were buried deep in the snow. Many days were spent shovelling snow using heavy plant and manual labour. A few enthusiastic fellow expeditioners also lent a hand in digging. After more than a week of digging, a few broken shovels, a blizzard, and then more digging because of it, the team was finally ready to peel back the covers off the biopiles and take the first soil samples of the season. It proved to be a tougher task than shovelling heavy snow, as the soil within the biopiles was frozen. The team persevered and completed the task. Now they are set to spend time focusing on another remediation site that is part of the team’s project schedule this season. And in the meantime, it will give the biopiles and PRBs time to thaw out.

Rebecca McWatters

Since arriving at Casey two weeks ago, we have been checking the progression of breeding by the Adelie penguins at nearby Shirley Island. Our work is timed around the different breeding stages of the penguins, so knowing what stage they are up to tells us how to time our work, which includes tracking the penguins’ foraging trips out at sea, doing population counts and collecting faeces for diet analyses.

When we visited Shirley a week ago in warm and still weather, all the birds appeared to have arrived and were sitting quietly in their densely packed colonies, but there was no sign of breeding activity. On Monday there was some courtship activity and mating. We only saw one nest with an egg. The next day however, egg laying was in full swing. 

Egg laying is spread over a few weeks, so the peak will happen in the next week or so. Females leave the nest for a long foraging trip a few days after they lay their second egg, so we expect to see them leaving the island soon. The males will be incubating the eggs in their absence. This pattern of breeding activity happens annually, but the timing varies from year to year, and a remotely operating camera on the island will monitor these timings all the way through summer. Expeditioners have been walking across to Shirley Island in the evening to watch the penguins while the fast ice still allows access.

Colin Southwell