Hanson Landfill > Sustainability

WOLLERT LANDFILL IS CLOSED TO THE GENERAL PUBLIC UNTIL FURTHER NOTICE, DUE TO GOVERNMENT COVID LOCKDOWN

Creating Habitat and Powering Homes with Green Energy

Situated in Melbourne’s northern fringe, Hanson’s Wollert Renewable Energy Landfill has provided households and commercial, industrial and demolition businesses with a facility to safely dispose waste since 2000. The Wollert facility is an excellent demonstration of Hanson’s commitment to developing innovative solutions that exceed the landfill best practice standards expected by the regulatory agencies, the Victorian Government and the community.

The Wollert Renewable Energy Landfill site is a repurposed former quarry, where tonnes of waste are deposited into cells that are then capped at the end of their landfill life. These caps are built using a ‘regulation’ layer of quarry scalps, processed clay (GCL), a linear low-density polyethylene (LLDPE), membrane, a layer of cushion geotextile, and an additional one-metre bed of quarry scalps as a growing medium.

Solar Panels — *380 solar panels make up the solar farm, powering thousands of homes*

Wollert landfill had found an innovative way to improve its environmental impact and service to the community. In 2016 it converted the capped portion of the site into a solar farm by installing more than 380 solar panels. This solar farm has the ability to generate up to 100 KW per annum. The solar powered installation operates independently, off the grid; exporting all the power it produces.

This green power production is further boasted by the onsite green power station that produces electricity from the landfill gas (methane) emitted from the decomposing waste. This electricity is then fed into the grid, providing enough energy to power to more than 5000 homes.

Since landfill sites are typically unstable and difficult to build on, once decommissioned they are often transformed into parks or other types of green space. Some of the best examples provide new habitats for native species.

At the Wollert Renewable Energy Landfill site, Hanson found a way to establish native habitat and improve biodiversity outcomes early. In 2010, with approval from the EPA, the site trialled a ‘phytocap’ (an evapotranspiration cap).

Hanson’s Land and Mineral Reserves Manager Daniel Fyfe says, "Establishing a phytocap is an innovative opportunity to develop a habitat for native flora and fauna utilising local indigenous species and meet the EPA requirements for capping and closure of landfill cells."

This initiative utilises deep beds of locally sourced soils, planted with suitable indigenous grasses, bushes and trees. The deep soil layer acts as a sponge for rainfall in winter. The plants transpire the moisture back to atmosphere during the summer months and preventing rainfall penetrating into the waste mass and the production of leachate.

The trial was successful; hundreds of trees, bushes and native grasses are now very well established, and the phytocap has been colonised by flocks of birds, insects and other fauna, including healthy mobs of eastern grey kangaroos.

Producing Alternative Energy

Wollert Landifill is operated as a renewable energy landfill with leachate recirculated back into the waste. This has resulted in a significant volume of methane gas being generated and then recycled as an alternative source of energy.

In fact, 1.4 million cubic metres of methane is captured at the landfill each month.

This represents approximately 85 percent of the total methane gas generated at Wollert and which is used to produce 55 million kilowatt hours of electricity each year, or enough energy to power 10,000 homes.

A Carbon Footprint study undertaken at the landfill indicates Wollert has a better greenhouse gas performance than many high-technology disposal systems proposed for Victoria. For more information, read our Comparative Greenhouse Gas Life Cycle Assessment.

Rehabilitation

Water Protection

Asbestos Handling

Wollert has a comprehensive approach to ensuring all asbestos is handled at the highest environmental standard.

This includes photographing eighty-five percent of all commercial asbestos loads to carefully monitor the delivery process. These photographs are also passed back to the customer if the waste is not properly wrapped and habitual offenders are banned from the site.

Wollert only accepts commercial asbestos materials that arrive with EPA Transport Certificates, wrapped twice in plastic, within strict weight restrictions and in a Ro-Ro bin so they can be slid on an angle into the landfill, rather than being dropped onto the ground.

In areas of the tip where asbestos is being received or handled, air-quality is monitored twice a year. To date, has asbestos fibres have never been more than 1/10th of the Occupational Health and Safety limits.

Asbestos is buried the day it arrives on-site and with the GPS coordinates of each asbestos load tracked, Wollert therefore has an ongoing record of exactly where asbestos is located within the landfill.

Refused Derived Fuel

Solar Leachate Distillation

Native Revegetation on the Capping