Our environment requires considerable and continual works to be carried out in order to establish, and then maintain on a permanent basis, pleasing and tolerable living conditions for mankind:
- the securing of territory whilst protecting, as much as is possible, people and goods against risks and catastrophes,
- the elimination of solid and liquid residues,
- maintenance of functional and landscaping features of human structures,
- improvement of the countryside in order to re-shape urban parks and old slag heaps and create recreational areas, leisure parks, ski pistes etc
It is frequently forgotten in our countries where nature has long since been tamed, that nature is naturally savage and inhospitable. We need therefore to protect ourselves against excesses.
Human activities also produce residues which must be treated.