Wastewater treatment at Scott Base

Brad Lawson is a water engineer at Scott Base in Antarctica. Part of his job is dealing with wastewater. Brad explains the processes for treating wastes – both for disposal and for shipment.

Question for discussion

• Why do you think it is acceptable to dispose of treated waste liquids on site but not the treated solids?

• Brad says they treat wastewater to a standard above what is required by the Antarctic Treaty. Why might they take extra steps to do this?

• How is wastewater treatment at Scott Base either similar or different to how wastewater is treated where you live?

Transcript

Voiceover

Antarctica New Zealand commits to undertaking all activities in a way that minimises impacts on the environment, both in Antarctica and New Zealand. All human activities in Antarctica produce waste. To minimise the environmental impact of these activities, Antarctica New Zealand has developed a waste management system and guidelines.

One major waste stream generated by humans in Antarctica is what gets flushed down the loo or deposited in field buckets! Another waste stream is dirty water from washing and laundry.

The wastewater system in Antarctica is set up so that some wastewater can be managed and returned to the ocean, and biohazardous waste like faeces can be managed and packaged to return to New Zealand.

Brad Lawson

This is where all the magic happens. This is where the bugs live and all the processing happens. Over this side, we have the main pipe that comes into the plant. So that’s all, where all the sewage from the rest of the base goes into this, which is the brush screen. This is what screens all the solids from the liquids. Basically, it’s a bit of mesh and literally like brooms that just spin around. So all the solids get pushed that way and all the liquids can flow through into this tank.

I’ll shut that because it gets a bit whiffy.

Those two pumps down the bottom, they will pump it up and into our pre-clarifiers. These are basically just like settling tanks. So they just hold the sewage and they also pump a bit of water into it. We actually have garden sprinklers in it – straight from Bunnings. So they’re on a timer. They just spray the water down on the sewage just to kind of break it up and dilute it a bit. 

So as the fluid gets pumped into the tanks – that flow from there to here – pushes the liquid that way. And this is where it separates from a liquid at the bottom, and the sludge all gathers at the top. It pushes it into our sludge tank at the end there.

This amazing Italian machine basically processes the sludge. It has these tea bags – basically just a large tea bag. It gets sucked up through this pump here and mixed with a polymer water mix, which acts as a binding agent, so it binds all the sludge together so it all holds instead of being fluid and flowing. Then it gets pumped up and down into this tank at the top, which separates it out. The sludge gets caught by the bag, and then the liquid can flow out around the bag. Then that liquid, which has already been processed, goes down into that drain there, which in turn heads out to the ocean.

Voiceover

All other liquid then flows through pipes, and ozone is pumped in to kill off any remaining bacteria before it is released back into the ocean.

Brad Lawson

I can show you guys a sample of the final product. It does a really good job. We’re well beyond like the Antarctic Treaty. We treat it well beyond what we need to. 

Offscreen voice

And then we take all the solids home, don’t we? 

Brad Lawson

Yeah. The corn bags get put in a box outside. They get put in a container and shipped back to New Zealand. And then we pump the sludge into another bag. Every bag gets double bagged and sealed very tightly and then that also gets shipped back home. Then some poor fella has to deal with it at the other end when it’s all defrosted.

Acknowledgements

Brad Lawson, Antarctica New Zealand

Footage of the Scott Base wastewater plant and all other stills unless stated, courtesy of Dianne Christenson and Carol Brieseman
Bathrooms and laundry room at Scott Base, cover of Antarctica New Zealand Waste Management System manual, wastewater plant schematic and ‘corn bags’ being filled, Antarctica New Zealand
Dianne Christenson and Carol Brieseman visited Antarctica with support from the Antarctica New Zealand Community Engagement Programme