Monday, November 07, 2011

Landfill and Groundwater Contamination

Approximately 100 million tonnes of waste are disposed of each year (comprising Municipal Solid Waste and Industrial/ Commercial Wastes) at the many licensed landfill sites operating in England and Wales. However space for landfilling at these locations is due to run out in the very near future, so many people need to be told about them, so that new landfills can be planned. It will always be necessary to have some landfills. Although zero waste is a great aspirational target, at some point before zero, the law of diminishing returns will always set in, and the energy used apart from the cost of avoiding that last few percent of waste, will always make zero waste an unachievable target.


When rainfall soaks into waste in a garbage tip it slowly drains through the waste under gravity. As it does so it picks up soluble contaminants from the waste itself. This produces a very strongly organically contaminated liquid which is called leachate. Most of the contamination is biological (organic) in nature, but whatever soluble contaminants are present in the landfill, the leachate will probably also contain them in small quantities. The leachate will also have dissolved methane in it if it comes from a gassing (biogas producing or âmethanogenicâ) landfill.


If there is no base lining the leachate will drain away through any reasonably permeable material which exists under the landfill. Although this material below the landfill may do some filtering and further cleansing of the leachate, it can enter the underground strata still in a highly polluting condition. Water flowing in subterranean rock, through cracks and fissures and through any permeable material is called groundwater.


In many parts of the developed ad developing world this groundwater will be used for drinking and cooking. It will obviously be dangerous to human health for people to imbibe this flow. This will happen if and when pumped out for use from contaminated strata, or where the groundwater emerges at the surface.


Groundwater moves slowly and continuously through the open spaces in soil and rock. If a landfill contaminates groundwater, a plume of contamination will occur wherever reasonably permeable material exists below, for example a private property plot.


Any groundwater which gets polluted will still keep flowing underground and although the ground may help to naturally filter and biologically treat the leachate, eventually the pollution flow may grow and the small extent of a polluted area shown initially may later have to be extended if a growing contaminant plume develops, and nearby water resources including water supply boreholes can be contaminated. If they do they will probably remain unusable for several generations. Such a loss of something as precious as water is a terrible problem for later generations.


So, is it any wonder that environmental activists dislike landfills not only because of the potential for pollution just described, however, the more astute among them also dislike landfilling because landfills permanently remove large quantities of raw materials from economic use.


All of the energy and natural resources (such as water) that were used to process the items "wasted" are also not conserved.


Environmental Protection Agencies in many countries generally rely on the laws in their states to enforce their own operating permits and federal laws. If state agencies are not aggressive, violations can worsen, multiplying negative environmental impacts exponentially. Environmental pollution of land, air, and water created by the world's poorly-managed landfills is enormous.


In the early 21st century, alternative methods to waste disposal have been devised, including recycling, converting to biodegradable products, incineration and cogeneration facilities, and sustainable development, all of which assist in reducing global landfill pollution.


Steve Evans is an authority on landfill liabilities and Global Warming effects visit any one of the product and resource links we give here and you will not be disappointed. Landfill Problems and Global Warming Effects are just two of many issues on which we comment, plus educational and general information available free, if you visit the Landfilling Site web site.

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