FACTBOX: Hidden riches in a rubbish dump

(Reuters) - A dramatic rise in the value of old plastic is encouraging waste companies to consider the possibility of mining existing landfill sites to reclaim and recycle their potentially valuable contents.

According to William Hogland, a professor in Environmental Engineering and Recovery from the University of Kalmar in Sweden who has researched landfill mining, the average composition of an old landfill could look like this:

MATERIAL UNSORTED %

Paper 9.7 percent

Plastic 4.9 percent

Nappies, sanitary towels etc 0.5 percent

Textiles 2.3 percent

Rubber 0.6 percent

Leather 0.0 percent

Glass, ceramics 0.3 percent

Metal 1.7 percent

Food waste 0.5 percent

Electronics 0.0 percent

Garden waste 1.1 percent

Wood 9.9 percent

Stones etc 13.7 percent

Hazardous waste 0.2 percent

Other rotten matter 54.5 percent

Hogland based this assessment on Swedish sites.