PROBLEMS associated with LANDFILL

Gases
Landfill is the cheapest way of disposing MSW, but all efforts to get rid of waste pollute the environment to some extent. In landfills the disadvatages are that gases and chemicals are released into the air we breathe. Experiments show that the gases and chemicals released from landfill sites are harmful to animals. Doctors suspect, therefore, that it is harmful to humans also. A major disadvantage is the release of Methane gas. This gas can be explosive and in the USA there have been over 30 explosions linked with Methane released from landfill sites. People have died as a result!

Early Landfills
Early landfills were put in convenient locations on the least expensive land. The waste was 'out of sight out of mind'. People did not realise that as the waste rots and decomposes, it can release toxic chemicals. Craigmuschat Quarry in Gourock

As rain washes through the waste tip, it dissolves some of the solids and mixes the liquids. The water can become acidic and eat into the waste in containers. All this produces a contaminated fluid called leachate. Leachate escapes from most old landfills. It can pollute or contaminate drinking water in the ground, modern landfills are designed to protect the environment from pollution. More recently, landfills have had barriers designed to keep in the leachate. Engineers line the quarry With clay or synthetic materials Which the leachate cannot easily pass through. Pipes then collect the leachate for storage in tanks and special treatment.

Bacteria
However, there is another problem with landfills, whether lined or not. Bacteria in the soil, break down organic matter in the landfill, such as vegetable peelings. As they do so, they release methane gas. Methane is not a poison, but it has two drawbacks. Firstly, it is a greenhouse gas. It contributes to the greenhouse effect that will eventually cause global warming. Secondly it is explosive. If it seeps from the landfill and finds its way into a building, it can build up unnoticed. One day someone lights a match and ………..BANG!!!


Greenhouse Effect
The Greenhouse Effect is caused by so called 'greenhouse gases' in the atmosphere. These gases, such as carbon dioxide, methane, and water vapour have existed naturally for millions of years. The amount of these gases has gradually increased, causing the earth to get warmer. The temperature of the Earth changes naturally by a few degrees, but it should take thousands of years. Over the next forty years the temperature could rise by another 1.50C to 4.50C, a speed of increase never experienced before on Earth. This increase in temperature could cause the huge polar ice caps to melt. This would cause sea levels to rise by about 1.5 metres over the next sixty years. Low Iying areas of land will be flooded and millions of people will lose their homes. So, Britain is at risk, especially coastal towns such as Greenock and Gourock.


Incineration
Another method is incineration, a method becoming scarce, therefore making it more expensive. One advantage of incineration is that energy can be produced from the burning waste and there are now some 'energy from waste' schemes in operation. With this method, some large lanfills generate enough electricity for 10,000 homes! One disadvantage of incineration is that even more gases are produced, contributing further to global warming.