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The Natural Cap – Sustainable solution for landfills
Published on 12 July 2019
Netherlands
Gelderland
This is the good practice's implementation level. It can be national, regional or local.
About this good practice
The Volgermeer (105 hectares) was a landfill for domestic and industrial waste. Large amounts of chemical waste have been dumped during the 60’s and 70’s.
Monitoring over 30 years showed that the natural occurring peat at the sideways and bottom contained the contaminations: an important feature preventing migration of contaminations. Because of demonstrated safe containment of toxic waste in peat, it will be used to “install” a natural impermeable peat cap to ensure a much longer lifespan of the capping than in the case that the impermeable capping was only based on the application of a HDPE layer. The living peat works like a sponge and will prevent large quantities of water to penetrate the landfill. As long as the peat layer is intact the isolation of waste is secured and the cap will act as a net carbon sink.
The Volgermeer has become an attractive location for science students and naturalists studying the peat formation. Together with the Centre of Wetland Ecology
research programs were initiated to study the growth of peat and to assess the effects on the quality of the capping (isolation) of the waste.
The Volgermeer stands out as example of turning a heavily poluted landfill into a (scientific) natural park open for public and education by making use capacity of nature itself to solve environmental problems.
Main stakeholders: municipality of Amsterdam; Ministry of Infrastructure and Watermanagement; Burgercomitee (local residents).
Monitoring over 30 years showed that the natural occurring peat at the sideways and bottom contained the contaminations: an important feature preventing migration of contaminations. Because of demonstrated safe containment of toxic waste in peat, it will be used to “install” a natural impermeable peat cap to ensure a much longer lifespan of the capping than in the case that the impermeable capping was only based on the application of a HDPE layer. The living peat works like a sponge and will prevent large quantities of water to penetrate the landfill. As long as the peat layer is intact the isolation of waste is secured and the cap will act as a net carbon sink.
The Volgermeer has become an attractive location for science students and naturalists studying the peat formation. Together with the Centre of Wetland Ecology
research programs were initiated to study the growth of peat and to assess the effects on the quality of the capping (isolation) of the waste.
The Volgermeer stands out as example of turning a heavily poluted landfill into a (scientific) natural park open for public and education by making use capacity of nature itself to solve environmental problems.
Main stakeholders: municipality of Amsterdam; Ministry of Infrastructure and Watermanagement; Burgercomitee (local residents).
Resources needed
The municipality of Amsterdam is responsible for monitoring and maintaining the natural capping. It is funded from their soil remediation budget .
Evidence of success
This practice is good in regions were peat is naturally occurring.
After four years of large-scale scientific research, the recipe for peat formation on the mineral soil has been defined. The Natural Cap starts to form slowly. Special natural values have developed.
The site open for public and visited for pleasure and educational purposes. The monitoring results to date show no spread of contaminants.
After four years of large-scale scientific research, the recipe for peat formation on the mineral soil has been defined. The Natural Cap starts to form slowly. Special natural values have developed.
The site open for public and visited for pleasure and educational purposes. The monitoring results to date show no spread of contaminants.
Potential for learning or transfer
This is an example of building with nature. Peat is a natural resource that can be used for groundwater remediation purposes and for isolating contaminated sites. Present peat around and underneath the location is for 99% intact and isolates the contaminations. The high concentrations of contaminations in the landfill, even after 30 years, do not spread towards the area around it. The peat can be seen as an active carbon filter. It allows for small quantities of water to penetrate but does absorb and/or filters contaminants. Because of this a new view has arisen compared to the conventional approach using foil and sheet piling to isolate a landfill site. Water pressure in the landfill site can decrease gradually because the water can flow through the peat filter towards the vicinity without the contamination leaving the area. In addition the presumption has arised that the presence of bacteria in the peat contributed to a large extent to the filtrating capacities of the peat.
Further information
Website
Good practice owner
You can contact the good practice owner below for more detailed information.
Organisation
www.tauw.nl
Netherlands
Gelderland
Contact
project manager