Monitoring Recycled Water Injection Into a Confined Aquifer in Sindos (Thessaloniki) Using Electrical Resistivity Tomography (Ert): Installation and Preliminary Results

Abstract

This work describes the installation and preliminary measurements of an electrical resistivity tomography (ERT) system to monitor the injection of recycled water into a confined aquifer in the area of Sindos. The aim is to provide, through time-lapse electrical resistivity tomography (ERT) measurements and processing, geoelectrical images of rather increased volumetric sampling around and between the holes and to obtain improved understanding of the flow and transport of the injected water. The details about the general setting and the design of the injection utility are presented and the construction and installation of the ERT cables into the boreholes are explained in full. Preliminary measurements involving single-hole ERT measurements were obtained and processed with a 2D inversion algorithm to produce images of the subsurface. Results depict a very good correlation between ERT images and the lithology logs an indication of the reliability of the approach. This images offer increased resolution and spatial coverage compared to traditional approaches. The entire ERT permanent installation is of low cost, easy to implement and can be used to understand and evaluate the effects of the water injection process.

Mapping and monitoring subtle ground deformation in Sindos, Greece, with high precision digital leveling

“…These deposits are unconsolidated to partly consolidated marine-lacustrine sediments, filling a NW-SE oriented tectonic graben, consisting mainly of sand and black silty clays (Rozos, Apostolidis, and Xatzinakos Fig. 1 Two recent, indicative stratigraphic columns of the broader area of Sindos (Tsourlos et al 2007).…”

“…The Neogene basement, buried by a 300-400 m thick sequence of Quaternary deposits, is represented by sandstones, red clays and outcrops in the north and in the north-east border of the area of interest (Raspini et al 2014). The materials that are found are mainly sands, red clays with calcareous compositions, and conglomerates (Tsourlos et al 2007) (Fig. 1).…”

Integrated Groundwater Resources Management Using the DPSIR Approach in a GIS Environment Context: A Case Study from the Gallikos River Basin, North Greece

“…(E.Y.A.Th., Thessaloniki, Greece) has undertaken a major project supervised and funded by the Greek Ministry of Environment, Physical Planning and Public Works to assess the impact of groundwater artificial recharge by means of injection of treated domestic effluent into a confined aquifer via deep boreholes at the area of Sindos [40]. Recycled water potentially represents one important portion of the water resources for covering the increased water demands in the basin.…”

The impact caused by tap water recharge on groundwater quality

“…However, most of them focused on the quality and congestion problems in use of wastewater for artificial recharge [8][9][10][11] and few exampled the use of tap water for artificial recharge of groundwater. Based on collected material and data available in some sporadic experiments about tap water recharge to A2, A3, and A4 from the 1960s to the 1980s, this paper gave some evaluations on the variations in groundwater characteristics, migration range of recharge water and various factors affecting groundwater quality during the artificial injection, so as to offer scientific basis for the large-scale artificial recharge in the near future.…”