This week at Casey: 20 February 2020

This week at Casey we take a look at what remediation are doing, some more boating pictures and a plane in the skies

Remediation - End of Season Update

One of our major tasks this season has been to construct a new containment area to store and clean-up (aka remediate) fuel contaminated soil. Avid followers of the project over the years (yes, we know you exist!) will be familiar with the long rectangular shape of our biopiles adjacent to the waste water treatment plant. This thin and long design (see picture) was used for the first iterations of biopile design. It was selected for ease of construction, limitation of the available plant and to trial different types of liners and combinations thereof. This was important as the types of liners needed to be proved and tested for this use in Antarctica. It had never been done before!

Real estate at Casey is very tight so as soil has become remediated and ready to be used on station, we’ve needed to look at ways to contain and remediate more soil while staying within the biopile site. So this year we designed a larger area for construction, colloquially known as the 'megapile'. This was possible through the years of testing, monitoring and operating the first iterations of the Casey biopiles. Through that we have since developed the capability to build a storage area that can store more soil and can be driven into by our specialised plant to more aggressively remediate the soil. Importantly, the design itself, from the preparation of the subgrade, to the types of liners used, to construction techniques including heat welding the plastic panels of liners together at Casey temperatures, has been informed by the research and monitoring conducted over many years. We have also been using our drone to get detailed elevation profiles to ensure we get the correct construction grades to maximize our storage space while minimising ponding of leachate (see images).

While the construction may look particularly plant heavy, the design and build process is quite complicated, given the conditions, lack of space in which to build and operate heavy plant, and the fact that part of the area where the biopile being built this year had to be excavated first (because it was heavily contaminated with fuel). Therefore, the construction of the megapile required a delicate dance of plant and personnel, science and application, that could not have been done safely without the skills and excellent support from station personnel. Thank you everyone!

- AAD Remediation Team

Graphic of the remediation site
Digital surface model of the new biopile
(Photo: Rebecca McWatters)
The remediation site in 2012 showing multiple biopiles
The remediation site in 2012 showing multiple biopiles
(Photo: Rebecca McWatters)
Seven piles of remediated soil along the coast at Casey
The seven biopiles are positioned so they are parallel to the prevailing…
(Photo: Rebecca McWatters)
Three heave plant vehicles working at a remediation site
The new biopile begins to take form
(Photo: Rebecca McWatters)
Three liners being added to the new biopile site
The various liners are added to create the containment bunding
(Photo: Rebecca McWatters)
Lining place in biopile area
The western side of the biopile is welded in place
(Photo: Rebecca McWatters)

A jumbo jet visit over Casey

On Sunday this week we were visited by a Qantas jumbo jet flying at about 12,000 ft. The plane was filled with around 300 people interested enough in Antarctica to fly down to have a look from up high. They circled around the station while we waved then headed down the coast towards Bunger Hills before heading back to Australia.

On board was James from the Australian Antarctic Division - Territories, Environment and Treaty section. He was an observer on this flight monitoring compliance under the authorisation for this season's tourism overflights.

The Qantas plane in the skies over Casey Station in Antarctica
The Qantas plane in the skies over Casey Station in Antarctica
(Photo: John Sommers)
Aerial view of Antarctic coast
Qantas overflight of Antarctica with a view of the Bunger Hills near…
(Photo: Australian Antarctic Division)
Aerial view of the Antarctic coastline
Qantas overflight of Antarctica near Casey station
(Photo: Australian Antarctic Division)
Aerial view of rocks and ice sheets of Antarctica
Qantas overflight of Antarctica near Casey station.
(Photo: Australian Antarctic Division)

Out and about in the boats

We’ve been out on a few boat trips around Newcomb Bay lately and as we mentioned last week have seen a number of leopard seals. There is of course other wildlife around also that is worth a mention.

Giant petrels are a rare sight. The one below was looking for a free feed off the leopard seal kill in the water, an unfortunate Adélie penguin. If you look closely there is also a small Wilson’s storm petrel dancing above the waves in front of it.

Southern giant petrel and Wilson's storm petrel in Newcomb Bay
Southern giant petrel feeding on dead Adelie penguin and Wilson's storm petrel…
(Photo: Charmaine Alford)
A boat full of eager expeditioners on the water in Newcomb Bay
Always something to look at
(Photo: Charmaine Alford)