DETERMINING OF MIX ZONE DUE TO SEA WATER INTRUSION BASED ON CHEMICAL APPROACH

Abstract

The coastal area represent the area whereabout solid resident population enough. One of negative impact of groundwater intake in coastal area is the happening of seawater intrusion. Contamination by water go out to sea to freshwater will take possession of the zone, so-called the mixing zone. Mixing zone represent one of coastal aquifer characteristic. Mixing seawater and freshwater happened in an mixing zone marked by smaller chloride concentration than chloride concentration the seawater. The chemical process that goes on at the zone for example ion transfer, disconnection of carbonate element, reduce the sulphate, addition of bromide concentration and rich of minor element like iodida, flourida and strontium. The chemical process can explain the system of mass transportation of mixing zone. The geochemical process of Mixing zone like dolomitization in zone used to explain the origin dolomite, disconnection of carbonate mineral (ion Ca2+ and HCO3-) at saturated condition, certification and forming of sediment of manganese and sulfide ore. If we know the system of mass transportation of] mixing zone so can make the management of groundwater quality in the coastal aquifer. Keyword : mixing zone, coastal aquifer, chemical process