Assessment of Shallow Groundwater Purification Processes after the Construction of a Municipal Sewerage Network

Abstract

In the present study, the impact of the construction of the sewerage network (2014) on groundwater quality was studied on the example of a middle-sized settlement in the Great Hungarian Plain and changes in water quality were assessed using GIS and multivariate statistical analysis. As a result of the pollution that has been going on for decades, the groundwater supply of the municipality has become heavily polluted. In the period before sewerage (2011–2013), clear spatial differences were shown in the degree of contamination in the area of the settlement: the degree of contamination increased in the direction of local groundwater flow. Based on our results, the construction of the sewerage network resulted in marked changes in the quality of groundwater wells. Our studies showed a clear decrease in the concentrations of inorganic pollutants (NH4+, NO2−, NO3−, PO43−). In the fifth year of the post-sewerage period (2019), the clear spatial difference between wells was eliminated. We have observed a strong descent (1.5 to 2 m) in groundwater levels in the post-sewerage period, the reason for that is clearly due to that wastewater outflow was eliminated. On this basis, it can be declared that the purification processes in the area have started, but at the same time, our results show that pollutants entering environment undergo a number of transformations and remain in the system for a long time.

Assessment of the natural vulnerability of underground aquifer aiming at the hierarchization of locations for the implementation of water supply and sanitary sewage systems in the municipality of Ananindeua/PA

“…Meanwhile, areas characterized as Medium vulnerability, in general, presented aquifers of the type of free, lithology of types of medium sand, thin and very sand (preponderantly) and clayey sand soil (to a lesser extent), as well as the distance from the top to the water table between 5 and 20 meters. In fact, pollutants can more easily pass through permeable rock and contaminate groundwater (Mester et al, 2021). Furthermore, it is observed that the High vulnerability areas present the same features of confinement degree and lithology as the Medium vulnerability areas, being distinguished from the last ones due to the parameter D; where the distance from the top to the water table in these areas was a maximum of 5 meters.…”

Comparison of Trenchless and Excavation Technologies in the Restoration of a Sewage Network and Their Carbon Footprints

“…Such leakage can facilitate the infiltration of pollutants into soil and groundwater, posing a potential hazard to water quality. Therefore, efficient development and maintenance of sewer networks are imperative not only to uphold environmental integrity, but also to safeguard groundwater reservoirs [4][5][6]. In the field of construction, as in many other sectors, the use of Environmental Product Declarations in construction regulations is still in its early stages in most EU countries.…”

Assessment of Groundwater Quality in Relation to Organic versus Mineral Fertilization

“…To analyze the potential pollution of groundwater resulting from organic and inorganic pollutants, a statistical approach is used. Research concerning the analysis of anions and cations content, whether through an integrated approach or the assessment of the sewerage network construction impact on groundwater quality, uses statistical tools, such as Principal Components Analysis, Discriminant Analysis, or Cluster Analysis [18][19][20][21].…”