Landfills in New Zealand
Wikipaedia describes the trasnformation from tip to sanitary landfill.
Waste Not Want Not
A landfill is a place to dispose of residual waste or rubbish. However, from a zero waste point of view a landfill is a waste of potential resources, and is also the cause of leachate, landfill gas and a potential source of health problems.
Environmental effects of landfills
Leachate is formed as rainwater runs through the accumulated waste.
Landfill gas is a mixture of gases created through the decomposition of waste.
The composition of New Zealand’s waste is shown in the pie chart with the top three categories of organics (23%), paper (15%) and timber (14%) adding up to 52% of the total.
need pie chart to insert
Each person in New Zealand in 2004 created 400 kg of household waste.
To encourage waste reduction, the Waste Minimisation Act 2008 placed a $10 levy on each tonne of waste disposed of at municipal landfills.
Benefits of landfills
Energy from gas
Redvale Landfill, owned by Waste Management NZ Ltd, has nine generators to produce electricity from the landfill gas it produces. Enough energy is produced to power the equivalent of 7,500 homes.
Protection of the environment
Modern, sanitary landfills are highly engineered sites with layers of storm water collection systems, clay and synthetic landfill liners with leachate collection systems to provide environmental protection from the effects of landfills. In information about Hampden Downs Landfill, Envirowaste outlines environmental management and monitoring, stormwater and groundwater monitoring and leachate control. A diagram depicts the layers of a landfill.
Many landfills are owned by local councils, while some are commercially owned and operated by companies.
- Envirowaste http://www.envirowaste.co.nz/index.php?page=disposals-landfill-operation
- Waste Management New Zealand Ltd https://www.wastemanagement.co.nz/site/webpages/landfills/
The number of landfills is reducing with more than 300 in 1995 now estimated to be less than 100. Resource consents for landfills are difficult and expensive to secure, and modern sanitary landfills with suitable protection for the environment are expensive. Also, no-one really wants a landfill close to their homes. This objection is often referred to as NIMBY: Not In My Back Yard.
The Circular Economy
The circular economy may reduce waste to landfill as material flows are of two types, biological nutrients and technical nutrients.
In contrast to a traditional linear economy (make, use, dispose) a circular economy aims to keep resources in use for as long as possible (make, use, reuse, recycle…)