The small islands of the South Pacific region, like many other parts of the world, arc (~\I\j riencing population growth and, more particularly, the movement of people into )11,1I1!1 urban centres. Most Pacific cities, especially the capitals of regional countries, arc locili ",I in naturally protected coastal waterways. This is a historical situation, arising from III,' need to provide protected deep-water harbours for ships, the main form of internaliol\,d travel and trade. These waters are protected by offshore barrier reefs, by islands or by ril(,1 ine deltas. However, these protective mechanisms also have the effect of limiting mix!II): of near-shore and open-ocean waters (Viles and Spencer, 1995). This provides an OPP(l1 tunity for problem materials, derived from human activities, to accumulate in the neill shore waters and the marine zone with which most people interact.