| Contaminant |
Effect |
| Cadmium, copper, zinc, lead, arsenic, mercury, nickel |
Potential to restrict growth of plants or completely prevent it.
Potentially harmful to humans if ingested. (either by direct or
indirect routes.) |
| Combustible substances, eg coke or coal dust (often associated
with rail way sidings and old mine heads) |
Potential for surface or underground fires |
| Aggressive substances, e.g. sulphates, acids, chlorides, alkalis |
Direct attack on building materials, most notably concrete foundations
and retaining walls |
| Phenols & Oil and Tarry substances |
Risk of contamination of water supply by deterioration of service
mains on site |
| Asbestos |
Considerable danger if inhaled, known to lead to asbestosis +
implicated in lung cancer |
| Flammable gases, e.g. methane, (associated with buried organic
matter) |
Potential for build up of explosive gas beneath buildings. May
lead to asphyxiation of building occupants. |