Is It Really Waste? The Case Of What Goes Into Our Green Bins.
Has anyone else ever questioned where their green waste goes when it gets picked up? What purpose could my autumn leaves and summer weeds really hold? I always found it suspicious that the council would really want something that simply rots and starts to smell pretty bad.
I was lucky enough to be able to find that this question bugged a few other people in the community and on-campus. I was even luckier to be able to organizing a tour of Veloia’s Bulla Recycling Facility, which takes a decent percentage of the green bins from the northwest metropolitan region, in order to answer our questions.
First Question: Why Should I Care About This?
Waste mitigation is becoming more and more of a key issue globally as it talked about in a broad range of areas. Funnily enough, this is normally framed in the same way that my grandmother would discuss it: as being directly related to an ecological and financial cost.
From the political realm where it’s talked about a hard-line financial figure, to economic business discussions referencing waste as a lost resource and to hoard of debates within the environmental sector that threaten to down every academic working in the field.
Any way you look at it, its mind boggling when considered in light of the facts. In Victoria alone, its recorded that between 2014-15 we generated 15.2 million tonnes of waste with roughly 4.12 million tonnes being diverted from landfill and a further 8.27 million tonnes being recycled. With only 1 million tonnes of that being organic waste that was diverted and re-purposed.
That’s more waste than I could ever imagine coming out of our entire country!
Especially considering the fact that these statistics may not count food scraps within the organic waste streams (But that is a personal gripe for another time). That’s a whole lot of sticks and leaves getting thrown around everywhere, potentially ending up in landfill or being diverted to a recycling plant like the one we visited.
Which segues us to introducing the lovely staff of Veolia who happily showed a bunch of enthused citizens around their Bulla Facility.
First Question Sorted: Now What Happens There?
As we found, there’s a lot to (pardon the pun) digest, when discussing Veolia’s Bulla facility. This is in regards to the scale of the operation that works to manage multiple tonnes of organic waste weekly as well as the science behind how they do it.
The condensed version is that our waste arrives and is thrown together in a few piles in order to compost and become a nutritionally-rich soil conditioner for use on parks and farms.
But, honestly, there is so much more to it than that!
In order to comply with our national standards set by the Environment Protection Authority (EPA) the Bulla Facility uses invessel composting. This process involves lumping the waste together (after it has been sorted by all manner of intimidatingly gargantuan machines) and storing it in sealed concrete containers in order to heat the waste (as a means of pasteurizing it) and eliminate pathogens.
This process acts to keep odors contained while also eliminating the potential for contamination that can occur when there is any food waste within the compost. This is important to avoid potential high-risk pathogens like salmonella from growing within the compost as this could potentially find its way into our food by way of the soil-conditioner produced. It has been suggested that this is how people contracted food poisoning from lettuce in 2016. Thankfully, the process of pasteurizing compost is becoming more known and implemented to avoid running this risk.
While normally this method of sealing organic waste implies depriving it of oxygen and processing it through a process known as anaerobic digestion. However, these nifty containers have purpose-built vents and fans in order to make sure that this operates like the more common conceptions of composting – i.e. aerobic digestion – as this actually helps to mitigate the production of methane.
Seeing as methane is about 20 – 25 times more potent than carbon, this decreases the potential for Greenhouse Gas Emissions (GHGE) being dispersed. This sadly isn’t the case within regular landfill sites where these materials would be packed in and sealed, leaving the decomposition to be deprived of the oxygen needed to limit the production of methane.
This last point becomes important when we refer back to how much organic waste is not diverted from landfill and the devastating effect that this has on climate change, let alone the environmental as a whole.
So There You Have It.
Someone should really make a Disney movie following the journey of a lone piece of organic waste. If I had been smarter I could have actually done that with this blog post. Alas, the story of Johnny the Stick and his miraculous journey from tree to bin to container to soil will not be told today.
Regardless, this tour made it apparent to me that we waste a lot. As such it’s our responsibility to make sure we act to limit the amount of waste we make. This can be by individually adopting handy behavioral processes like the 5 R’s.