Contribution to Hydraulic Characteristics of Plio-Pleistocene Deposits of Thriassion Plain of Attica

Kontakiotis

et al. 2022

Water

The Thriassion Plain, the Saronikos Gulf and Eleusis Bay, Western Attica in Greece, receive pressures from the enormous industrial activity, as well as the Athens metropolitan area and the Piraeus port. Therefore, it is considered as brownfield in the Eastern Mediterranean Sea. The multi-component industrial activity has impacted the soil, the groundwater of Thriassion Plain and the coastal marine sediments of the adjacent Eleusis Bay, part of Saronikos Gulf as well as a brackish lagoon, Koumoundourou Lake. The industrial activity is expressed by high contents of metals, and oil products. This study presents the pollution record of selected published papers that indicate the temporal evolution of legislated polluting compounds, supporting researchers to provide solutions and policy makers to focus on the whole spectrum of potential policy alternatives.

Section: The Groundwater Status-pollution and Hydro-geochemistrymentioning

confidence: 99%

Integrated Ecological Assessment of Heavily Polluted Sedimentary Basin within the Broader Industrialized Area of Thriassion Plain (Western Attica, Greece)

Makri

Kontakiotis

et al. 2022

Water

“…The coastal clay strata prevent the lower standing aquifers from direct seawater intrusion where groundwater of good quality was found 90 m below sea level (m.b.s.l.) [37,38]; (a.2) the Pleistocene system, made up of marls with lignite layers in places, sands and marly limestones which is a multi-layered confined aquifer. There is Pleistocene sediments recharge and preferential lateral flow from the carbonate basement.…”

Section: Geology and Hydrogeological Characteristics Of The Study Areamentioning

confidence: 99%

“…Recent detailed hydrogeological research studies [37,38] have recalculated the aquifer characteristics, providing a revised hydrogeological model of three distinct groundwater hydrostratigraphic units (including their subunits): (a) the Neogene-Quaternary sediments comprising (a.1) the Holocene -Upper Pleistocene aquifer system, generally unconfined and semi-confined consisted of clays, sands and gravels. It is recharged by rainfall and upward leakage from lower aquifers.…”

Section: Geology and Hydrogeological Characteristics Of The Study Areamentioning

confidence: 99%

The Environmental Impact of a Complex Hydrogeological System on Hydrocarbon-Pollutants’ Natural Attenuation: The Case of the Coastal Aquifers in Eleusis, West Attica, Greece

Makri

Stathopoulou

et al. 2020

JMSE

The study area is the Thriassion Plain, an important area, in antiquity, surrounding the famous ancient town of Eleusis, 20 km west of Athens. The modern town and port and the entire area were heavily industrialized (1965–1995) coupled with unregulated urban and agricultural development. The presence of two crude oil refineries and other oil-related industries have strongly impacted the entire environment, including soils, waters and sediments of the broader area. The purpose of this work is to better understand how a multi-layered groundwater system affects the potential underground spread of certain fuel volatile compounds, namely the BTEX (benzene, toluene, ethylbenzene and total xylenes) as well as their attenuation after their direct or indirect release into the aquifer system. The spatial distribution of BTEX in groundwaters show that they were concentrated mainly in four rather restricted locations. Three of them were spotted, as expected, in the close vicinity of known pollution sources (a military airfield and two crude oil refineries). The other one corresponds to an abandoned site with no outstanding pollution sources where wells exist, eventually used for illegal dumping of oily wastes. It is important that the concentrations decrease significantly from autumn to spring. This decline could be characterized as natural attenuation, related to natural dilution phenomena and a flushing out of pollutants discharging through underwater springs to the sea during the rainy period (October to April). This, in turn, could be associated to the specific geological conditions affecting the hydrology, such as the unconsolidated non-permeable deposits and the multi layered formations of the area’s aquifers.

“…The geometry of the deposits cannot be described in details, or their total depth, which is likely to be about 300 m (Skianis and Noutsis, 2008) Pleistocene to Holocene age that include clays, sands, gravels and pebbles, often forming breccia-conglomerate banks with low groundwater yields. The upper aquifer is generally unconfined and locally confined (Hermides et al, 2016).…”

Section: Geological Society Of Greece 228mentioning

confidence: 99%

The use of geochemical ratios in groundwater quality assessment: the case of the Thriassion Plain, Attica, Greece

Makri¹,

Psychogiou

et al. 2019

geosociety

This paper is an effort to assess the groundwater quality and the geochemical processes mainly using the Chadha's diagram which classifies natural waters and documents the Piper and extended Durov diagrams. Chadha's diagram is a useful tool to interpret groundwater geochemical processes because it is produced by simple spreadsheets excel files. The example of hydrochemical analyses were given from groundwater samples of the Thriassion Plain. To attend our objective, 38 groundwater samples were collected. Hydrochemical sections, XY diagrams, distribution maps of ionic ratios as well as the Gibbs diagrams were used to identify origin of salinity and the hydrogeochemical processes that have taken place. The Gibbs diagrams have shown that evapotranspiration (ET) and rock-water interaction play an important role to the increase of groundwater salinity. The interpretation of Chadha diagram highlights that the stratigraphic factors and especially the clay strata occurrence have isolated fresh groundwater from seawater. The abundant occurrence of clay deposits to the depth of the plain work as barriers to direct seawater intrusion. Good quality groundwater identified confirms the important role of clay strata. Reverse cation exchange, is the predominant geochemical process in the Thriassion Plain aquifers, whereas evapotranspiration (ET) andVolume 55 rock-water interaction play an important role to the increase of groundwater salinity.