Study Area
The Vegoritis hydrological basin (Fig. 1) is environmentally sensitive; within its boundaries, there are four inland lakes that are hydraulically connected by swampy areas.
Three of these lakes are very shallow; most of their area is less than 1 m deep. Any change to their level has a great impact on their areal extent and also affects the other lakes downstream.
Extensive mining and agricultural activities are taking place in the basin, including five open cast lignite mines; these produce 55 9 106 t of lignite and 290 9 106 m3 of waste material annually (DEI internal report 2005; Dimitrakopoulos et al. 2003).
We have focussed on the environmental aspects of Vegoritida Lake, as it is the final receiving body of the surface runoff of the basin and considerable changes of the water level of the lake have been observed during the period of 1957–2007
(Dimitrakopoulos et al. 2003; Vavliakis et al. 1993).
The initial drawdown can largely be attributed to water use by the hydroelectric power plants located in the area but these extractions have diminished during the last 20 years, while withdrawal for irrigation and other uses have increased.
Additionally, the exploitation of the lignite mines has environmentally affected the land and water resources of the area, due partly to the dewatering measures undertaken
to protect the mines. The Amynteon mine, also located in the Vegoritis basin, began exploitation in 1989.
The average lignite production is 8 9 106 tn/year and the average excavation is 7 9 107 m3/year. The mining method is continuous surface mining, using bucket wheel excavators,
spreaders, and belt conveyors.
The depth of the mine is about 150 m. Extensive dewatering takes place to protect the mine from groundwater.
On average, 7 9 106 m3/year of groundwater are pumped out annually (period 2005–
2008), using water wells in the periphery of the mine.
Lavrion is located 40 km southeast of Athens.
The first traces of mining activity in the area go back to 3.000 BC.
Systematic and intensive exploitation of the silver and lead ores, though, started with the birth of the Athenian Democracy in 508 BC, the glory of which was based
substantially on the Lavrion mine.
Later, mining declined, and then was restarted in 1867 by a French-Italian company.
The natural landscape and the rich forest vegetation deteriorated.
Mineral wastes containing potentially toxic metals were dumped on the surface, covering extensive areas.
In 1989, the company ceased mining, and the area faced a serious economic crisis, in addition to its environmental degradation.