Safe Use of the Assimilative Capacity of the Marine Environment for Waste Disposal – Is It Feasible?

For centuries the sea has absorbed a variety of inputs from rivers, streams, salt marshes and the atmosphere. It is generally accepted that additional limited inputs by man are unlikely to have a significant effect on the marine environment. Various control systems have been constructed to provide a framework within which the regulation of anthropogenic inputs can be achieved. These are briefly reviewed. With care, and in the light of past experience in both freshwater and marine environments, reasonable assumptions or estimations can be applied where uncertainties exist; safe limits can therefore be set for discharges. Case histories are used to illustrate the contention that it is possible to assess the assimilative capacity of a marine area to receive wastes. There is a major distinction to be drawn between contamination and pollution of the marine environment. Moreover, acknowledgement of the assimilative capacity concept in the marine environment does not automatically provide dischargers with the right to utilise that capacity either in part or to the upper limit. What it does is indicate the upper limit which must not be exceeded if pollution is to be avoided, and provide an indication to the control authority of the safety margin involved in the discharge limits they set accordingly.