Environmental Protection Agency Victoria and Bill Clarke of the University of Queensland explain the challenges involved in landfill planning for state government authorities.
Managing a landfill after it closes could last up to 30 years, the Victorian Auditor-General’s report into managing landfills in September 2014 found. The publication notes that closed landfills can potentially discharge landfill gas for more than 30 years after they last accept waste. If not captured and destroyed or converted to renewables, landfill gas can be bad for the environment.
Bill Clarke, Professor of Waste Management at the University of Queensland, argues it’s difficult to ascertain how many closed landfills there are and that even some small operating sites can fall below licensing and reporting requirements. Together with an increasing awareness of the environmental impacts of landfill, greater demands are being placed on the auditing resources of governments and planning authorities. Bill says that an example of this includes the recent limits placed on manufactured chemicals called per-and polyfluorinated alkyl (PFAS) substances. State environmental protection authorities such as Queensland and New South Wales have prescribed specific limits to PFAS concentrations in waste, while others such as Victoria don’t allow PFAS-contaminated material in landfill.
With state government plans to keep the amount of waste out of landfill over time, more landfills are closing. Environmental Protection Authority (EPA) Victoria in its Assessing planning proposals near landfills June 2016 notes that at the time of publishing the document, Victoria had 79 operating landfills and more than 200 closed facilities.
“There’s a big debate occurring as to what insurances a landfill operator should provide after their landfill is closed and stops receiving revenue. Regulators require that the post-closure costs to monitor and manage the emissions from a landfill be incorporated into gate fees while the landfill is operating,” Bill says.
In Victoria, Tim Eaton, EPA Executive Director Knowledge, Standards and Assessments, says the location and estimated closure date of landfills is critical to planning. He says having a clear and consistent way of ascertaining closed landfill risk across the state will assist EPA in understanding the level of effort required to deal with landfill risk and how to prioritise its allocation of resources. EPA Victoria has been investigating its unknown landfills, and has developed a series of guidelines and programs.
Who owns the landfills in Australia?
The largest sites in Australia are run by private companies, while local councils are responsible for landfills in their municipalities. Federal Government data from the National Waste Management Database shows there are around 600 officially registered sites, and up to 2000 unregulated ones. Bill says the smaller unregulated landfills are more difficult to ascertain, as state governments have set a cap on the number of tonnes a landfill needs to process before it must register its name. In Queensland, a facility must receive at least 50 tonnes a year in order to be classified as an environmentally relevant activity.
“Energy companies can capture the gas, which is normally profitable while the landfill is operating, but will eventually run at a cost when the flow of biogas is too small to viably run gas engines.
“Of course, the company that owns the landfill has to pay for that, that’s the idea. Companies have to incorporate into their gate fee an allowance for this aftercare.”
Bill says another major challenge is urban encroachment, as various EPA bodies need to manage this with state planning authorities.
“There’s thousands of landfills around Australia, so it’s a matter of the agencies having the capacity to manage these. The landfills that are licenced and managed are managed well,” Bill adds.
In Victoria, statutory authority the Metropolitan Waste & Resource Recovery Group has developed a four-year program known as the Local Buffer Support Program – collaborating with local government and state agencies to plan and manage the impact of urban encroachment. Through the program, authorities plan to develop buffers for waste and resource recovery facilities, so homes aren’t built in close proximity to closed and existing landfills.
In Victoria, landfills that service less than 5000 people are exempt from being licensed by the EPA. However, any new municipal landfill cell that is created or constructed after 25 June 2017 will need to apply for a works approval to construct the new cell. Prior to then, only municipal landfills servicing more than 500 people were required to apply for a works approvals for the construction of new landfills.
And as far as managing unlicensed landfills go, Tim says if the EPA is advised of a particular issue at an exempt landfill, an inspection will be undertaken and regulatory actions will be carried out to address unacceptable risks.
He says that in 2014, the Victorian Government established seven statutory authorities to publicly identify open landfills exempt from licencing.
“EPA region staff are aware of landfills below the licencing threshold in their region, and have previously inspected these sites at any time,” he says.
Bill notes that Victoria has an effective method of monitoring and setting guidelines for landfills across the state though its Best Practice Environmental Management – Siting, Design, Operation and Rehabilitation of Landfills guidelines. The guidelines set the classification of landfills, best-practice design, operation and siting considerations, including the approval or assessment of new and existing landfills.
Read the full story on page 28 of Issue 13.