ABSTRACT
The diagnosis has been completed and the risk evaluated, before considering a plan of remediation, one ought to decide whether or not remediation and rehabilitation actions are needed. The choice of a plan of remediation involves a number of factors which can be divided into two distinct groups: technical criteria and economic constraints. Irrespective of the technology used, three modes of application of remediation operations can be identified. These 'modes of treatment application' are: application of treatment away from site, application of treatment in situ, and application of treatment on or near site. It may be better to base classification on the technology itself, by distinguishing five groups of methods. The methods include physical methods, whereby the pollutant is extracted by physical means, from where it is found in the medium and whereby the pollution is physically immobilised on the spot, either by confinement or by stabilisation. The methods also include chemical or electrochemical methods, thermal methods and biological methods.
