International Groundwater Resources Assessment Centre Introduction to Groundwater

International Groundwater Resources Assessment Centre Introduction to Groundwater Dr Neno Kukuric Thessaloniki, 2008

Groundwater reserves

Where is the groundwater?

Hydrologic cycle

Groundwater Flow

Confined & unconfined aquifers

What is aquifer l Aquifer means a permeable water-bearing underground geological formation underlain by a less permeable layer and the water contained in the saturated zone of the formation;

Hydrogeological classification l Aquifer = Rock with medium to high permeability l Aquitard = Rock with a low permeability l Aquiclude = Rock with (almost) zero permeability l Aquifuge = Rock with zero permeability and no water

Porosity Types

Residence time

Hydrogeological methods l l Hydrogeological mapping Drilling Monitoring Geophysical methods l l Geochemical methods Modelling l l l Surface techniques Remote sensing Analytical Numerical (FDM, FEM, AEM) Synthesis and Analysis

Hydrogeological models

Sources of groundwater contamination

Sources of gw contamination

Sources of gw contamination

Sources of gw contamination 1 l Point sources l l l On-site septic systems Leaky tanks or pipelines containing petroleum products Leaks or spills of industrial chemicals at manufacturing facilities Underground injection wells (industrial waste) Municipal landfills Livestock wastes Leaky sewer lines Chemicals used at wood preservation facilities Mill tailings in mining areas Fly ash from coal-fired power plants Sludge disposal areas at petroleum refineries Land spreading of sewage or sewage sludge

Sources of gw contamination 2 l Point sources l l l l Graveyards Road salt storage areas Wells for disposal of liquid wastes Runoff of salt and other chemicals from roads and highways Spills related to highway or railway accidents Coal tar at old coal gasification sites Asphalt production and equipment cleaning sites Non-point (distributed) sources l l l Fertilizers on agricultural land Pesticides on agricultural land forests Contaminants in rain, snow, and dry atmospheric fallout

Groundwater Contamination