Nitrate pollution in the coastal aquifer system of the Korinthos Prefecture (Greece)

Over the last decades intensified agricultural production is applied in the northern coastal part of
Korinthos Prefecture (Peloponnese, Greece). An aquifer system occurs in the recent basin deposits,
which consists of unconsolidated material, namely sands, pebbles and fine clay to silty sand sediments.
A network of production boreholes and wells distributed over the studied region were sampled in June
1998 and the waters analyzed for major ions, nitrites and ammonia. Quality deterioration was detected
and attributed by crop overfertilization and use of abandoned shallow wells as septic tanks, inducing
increased nitrogen compound concentrations. Nitrates are noticeable throughout the entire region rendering
most of the analyzed waters improper for human consumption, as concentrations by far exceed
50 mg l-1. Mean nitrate concentration in the groundwater is 74 mg l-1 and the standard deviation 72. In
general, low nitrate concentrations were observed in wet seasons.