There are many thousands of closed landfills in the UK. In general all domestic waste landfills filled before the 1950s now exert little or no environmental impact as they contained a low organic content from the start. They did not ever become significantly methanogenic (methane producing), and were:
- normally shallow (2 to 5 metres deep),
- contained a great deal of ash and clinker from home fires,
- were rarely capped with a substantial thickness of soil materials,
- and they were as a result, sufficiently permeable to be “flushed” by percolating rainwater.
The leachate such sites produced was dissipated by dilution and dispersion, without any really structured decisions being made at all about the impact this might cause on the natural environment Fortunately, this did not matter greatly as the effects were short lived and localised.
The leachates they produce today will have slightly elevated salinity, metals, potash etc, but ammonia levels will be very close to background concentrations. Many have been developed as car parks, playing fields etc, and even built-upon with no ill effects, as long as suitable foundations to limit settlement, have been installed, and any soils contaminants are sufficiently deeply buried not to affect topsoil quality.
The result in these landfills is a well composted waste residue, which gives no odour if excavated, and even uncapped “tips” can now support substantial stands of trees.
The presence of these old landfills has only been systematically mapped since Local Authority contaminated landfill registers were introduced in the late 1990’s.
The UK Environment Agency’s “in my backyard” web site, shows some of the most recently closed landfill sites, alongside active sites.
How Closed Landfills Changed
During the 1960s, transport links improved, the sites each became larger, plastics entered the waste stream, and with improved affluence, waste tonnages rose. Home fire generated ash and clinker diminished progressively, alongside the cessation of home burning of organic and calorific value materials. Gas or oil fired central heating was installed in homes across the nation, and Clean Air Act regulated restraints on home burning, became the norm by the mid 1970s.
Without most of us realising it at all, we had created all the conditions necessary for today’s monster landfill “super” sites, with their ensuing need for containment and all their other emissions problems.
These landfills were built before there was any national regulation, and were not lined. For more information on landfill lining see our landfill lining development section.
Landfill linings are physical barrier systems intended to, as far as possible, prevent the escape of water and gases out of the body of the landfilled waste. A Landfill Liner is placed at the bottom and sides of modern landfills and are continuously welded to as far as possible provide a watertight seal. They are […]
In this article we make the prediction that all UK Landfills will close within 5 Years. The current trend in waste reduction/ diversion from landfill shows that the nation will achieve Zero Waste to Landfill and quite soon as well. That momentous occasion will take place in 5 to 6 years time, according to the figures […]
The Evolution of Landfill Lining Design in the UK from Dilute and Disperse to Full Containment The image above is one that we published back in 2004 and is one of the most important progressions in the history of landfills in the UK. It was a webpage in itself and rendered in efficient HTML code […]
Here is an explanation of the requirements of the DSEA Regulations and what they mean for landfill site owners and operators. All landfill owners (and by delegation their operators) fall under this regulation, and must act in order to comply with Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) which have been in force since July 2006. DSEAR – […]