Open AccessQuali-quantitative considerations on low-flow well purging and sampling
Author(s) -
Giuseppe Sappa,
F. Filippi
Publication year - 2021
Publication title -
acque sotterranee
Language(s) - English
Resource type - Journals
eISSN - 2280-6458
pISSN - 1828-454X
DOI - 10.7343/as-2021-526
Subject(s) - representativeness heuristic , sampling (signal processing) , context (archaeology) , aquifer , groundwater flow , sample (material) , groundwater , environmental science , field (mathematics) , hydrology (agriculture) , computer science , engineering , geology , statistics , geotechnical engineering , mathematics , paleontology , chemistry , filter (signal processing) , chromatography , pure mathematics , computer vision
This article deals with both the main advantages and issues related to groundwater purging and sampling that are usually carried out through the so-called low-flow methodology or with the method based on the purging of 3-5 well volumes, which is still widely used in environmental monitoring. A review of the recent literature concerning the technical characteristics, innovations and modelling related to low-flow sampling is presented. The aim is to provide to the reader a broad overview on this specific field application and offer a new vision, which considers two aspects: 1. The qualitative aspect, relating to the representativeness of the sample taken through a correct purging of the monitoring well and the consequent correct interpretation of hydrochemical data; 2. The quantitative aspect, related to the possibility of using water level data during purging and low-flow sampling operations to estimate the soil horizontal hydraulic conductivity, without further investigations. Low-flow sampling methodology can be very useful especially for alluvial aquifers, providing representative samples of groundwater and hydrodynamic characteristics of the aquifer, with reduced costs and times. These two aspects are both important in the context of an environmental monitoring plan for a potentially contaminated site.