Follow-up surveys mean chemical and biological surveys both during and after acute pollution. It should be possible to utilise the results of such surveys both during the combat phase with regard to evaluation of relevant measures for optimal combating of the pollution, and in the restoration phase with regard to identification of resources that have been harmed. Such surveys may require special instrumentation and technical measuring equipment, particularly in the event of underwater discharges for surveys in the water column.
Source: Guidelines Regarding the Activities Regulations, Norway, updated December 2012. Regulatory Guidance