Waste Services

TAS Landfills

What is a landfill, and how did they get such a bad name?

Landfills are the oldest and most common form of solid waste disposal.

Originally, they were just open holes in the ground where we dumped our rubbish. Old landfills were unmonitored, attracted disease-carrying pests, and created widespread contamination.

It wasn’t pleasant. Everyone had to put up with dust, bad odours, and noise pollution. But then we discovered that landfills were also having a major impact on global warming and our health.

Things had to change.

Today, Tasmanian landfills are precision-engineered structures. They’re designed to protect the environment from pollutants and are managed under strict regulations.

Let’s take a closer look at how they’ve improved.

Modern landfills have revolutionised how we manage waste while keeping our environment safe

  • These days, our design approach is ‘environment first’
    Landfills usually have independently monitored Environmental Management Systems to help deal with environmental threats. Landfills also operate under strict Environmental Protection Authority (EPA Tasmania) licensing requirements. These protect the surrounding land, air, and water.
  • Contaminated water no longer escapes
    We know how easily contaminated water (leachate) pollutes the surrounding soil and groundwater. So landfills are now designed to collect and safely treat or process the leachate. This is usually done in lined leachate ponds or through a sewage system.
  • Harmful greenhouse gas can be safely collected and repurposed
    Some of our Tasmanian landfills are able to capture and clean-burn the toxic methane emissions. And, of course, the fewer greenhouse gases entering the atmosphere, the better. Scientists have also developed ways to generate clean energy from the collected methane.

But why was it so important to reform our landfill systems?

No one could ignore that using a simple hole in the ground for dumping landfill created many environmental challenges.

We started considering what the future might look like if nothing changed.

Experts began exploring some of the biggest issues, such as contamination of the surrounding soil and water from leachate, and the excessive levels of greenhouse gas emissions – particularly methane.

As expected, landfills were found to be a significant contributor to both the global climate crisis and polluting of the surrounding ground, water, and air.

  • Moisture seeping through landfills spreads pollution
    Leachate is the name for contaminated water that has percolated through landfill waste. Percolation is a welcome process when we’re brewing coffee. But the result is devastating at a landfill site.
  • Landfills generate lots of harmful gases
    Ammonia and sulphides are usually responsible for the stink. But it’s the greenhouse gases methane and carbon dioxide that make up the bulk of landfill gas and present a huge threat to our planet.
  • Food scraps and organic matter can’t decompose naturally
    Because they’re regularly compacted, landfills are a low-oxygen environment. This means green waste and other organic material buried inside them cannot break down naturally and release methane instead.
  • Landfills are a top source of methane emissions
    Methane has more than 80 times the warming power of carbon dioxide over the short term. And because of the large amount of methane they release, landfills are a major cause of man-made global warming.
  • Waste arrives, and specialised vehicles compact the waste and remove air pockets to make the most of the limited landfill space.
  • The types of waste we’re regularly sending to landfills are:
    • Inert waste that isn’t chemically reactive and won’t decompose
    • Clean fill and building materials
    • General household and commercial rubbish, including food waste
    • Hazardous waste requiring an EPA licence, such as asbestos
  • With each delivery, the type and volume (weight) of waste is recorded and a landfill waste levy is calculated. Of course, the more reusable and recyclable material kept out of landfill, the smaller the fee.
  • At the end of each day, the active waste area is covered with soil, sand, or crushed glass to stop pests and help contain the litter and odours.
  • Once a section of landfill reaches its maximum height, it’s sealed with a layer of clay to prevent rain from seeping in. Then it’s topped with soil ready for revegetation.

Landfills are no longer just a hole in the ground

Like a giant container set in the ground, modern-day Tasmanian landfills are lined to keep anything nasty from leaking out into the water, soil, and air.

They’re even capped once a landfill cell is full to stop anything else from getting in.

In fact, the entire process is scientifically designed to operate efficiently and protect our environment. Right from the construction stage, to how waste is delivered and processed, and through to the long term management of the landfill.

Nothing is overlooked.

As well as specialised engineering and maintenance, landfills must also comply with ongoing monitoring and regulatory controls.

There are strict EPA Tasmania licencing requirements that our landfills need to meet.

Plus, regular environmental audits are carried out to check the protection of the environment.

  • Each landfill is a series of cells, all built with the same incline, so the liquid drains in the same direction
  • Under advanced machine guidance, waste is spread evenly in a cell and then compacted
  • Cells are lined with a complex barrier that collects liquid and prevents any contaminants from spreading
  • Contaminated liquid drains into a nearby sealed leachate pond
  • Pipelines are used to direct the leachate into the sewerage system for safe processing
  • Each layer of compacted waste is covered with a layer of inert material to stop rodents and odours
  • Once at their maximum height, waste cells area covered with a layer of clay to prevent rain from seeping in
  • Completed cells are topped with soil, and revegetated
  • Greenhouse gas emissions are extracted and managed for the life of the landfill

Controlled or hazardous waste can’t go straight into Tasmanian landfills.

Anyone dumping certain types of hazardous waste will need a special permit from EPA Tasmania before landfills can accept it.

For southern Tasmanians, the Southern Waste Solutions facility has a purpose-built waste cell to deal with non-liquid hazardous waste.

The good news is, there’s always room for improvement

There’s no doubt modern landfills are kinder to our environment. However, these upgrades come at a cost.

What’s more, landfills are not ‘set and forget’ systems.

Local governments may need to fund landfills up to 100 years past their end of life to ensure the buried waste is managed through to a safe state.

Put simply, modern landfills are not economically sustainable.

It makes no sense to continue throwing our waste into landfills without a second thought. We pay to dump it. Then we pay more to manage the ongoing environmental consequences of the landfill.

It’s time to make better choices to reduce what waste we generate. And we should also start extracting the full value of our materials through reuse and recycling.

Forget convenience. Landfills are now our very last resort.

Adopt the waste hierarchy steps: ARRR! And encourage others to do the same. This is how we begin setting the foundation for a circular economy and a sustainable future.

Avoid. Reduce. Reuse. Recycle.

That’s one step closer to making a positive change.