Watch Can We Help in high quality on iviewwatch on iview
What happens to our landfill rubbish? Susie, ACT
[Pete] Now there’s not a lot of micro tips anymore are there, like we used to have?
[Brian Fox-Lane, National Manager, Boral Waste Solutions] The old tips of 15 or 20 years ago were really uncontrolled and they didn’t have good environmental standards so now we’ve got a much smaller number of landfills which are well managed around Australia.
From midnight to 5pm every day, trucks roll in to the Boral Western landfill site from all over Melbourne. The trucks are weighed on the way in and calculations are done to establish just how much rubbish is being deposited. The site is an operating quarry and as long as they keep digging the holes, we’ll keep filling them with rubbish.
Despite a 70% increase in domestic recycling in Australia over the last 5 years we’re still sending more and more waste to landfill each year.
[Brian] I think if you look at it at a household level we’re generating about 1 ½ tonnes per household in Australia of waste. That’s waste and recyclables. Of that about ½ a tonne is being recycled and the other tonne is still going to landfill. So we’re still producing a lot of waste.
[Pete] In a world ranking, are we poor?
[Brian] We are one of the big waste generators, maybe the US is higher than us. Per capita we’re probably number 2.
[Pete] Let’s hang our heads in shame.
[Pete] What’s that?
[Brian] That’s a compactor and that’s a pretty big machine. That’s a 55 tonne machine and it’s crushing the waste and compacting the waste and that waste will only take up one fifth of what it used to before it came into the site. The waste comes in every day and at the end of the day you put in a soil covering over the top of that and that’s stopping the birds and any environmental problems and then the next day more waste comes in so you’re building more layers and compacting that waste each day.
[Pete] Starting from the bottom up, what do you do when you’re designing a landfill site. What happens?
[Brian] Well one of the primary things is to make sure that you get the liner system right and at this site it’s a 1 metre thick clay liner and then on top of that you’ve got this HDPE or plastic which stops that leachate going through into the ground water. Rainfall that falls on the active waste is called leachate because it contains contaminants and that goes through into the liner system or collected on the liner and we collect that and really just make that safe and eventually re-use it. So we’re stopping it going through into the environment.
There’s one more welcome surprise.
[Brian] We drill vertical wells into the waste and then we collect that gas and send it off to the Biogas-to-Energy Plant where we generate electricity. There’s 3 big engines here, like car engines in a way but they're just on a much larger scale. So instead of turning the wheels of the car, they’re turning a generator and producing electricity which we export into the national grid. So we’re saving about 80,000 tonnes of carbon dioxide equivalent, so that’s a big greenhouse saving and stopping that going into the atmosphere, producing a lot of electricity, about 3 megawatts of electricity and that’s enough to produce power for about 3,000 houses.
[Pete] Goodness me. Good work Brian.