This part of ISO 5667 gives guidelines for the design, construction and installation of groundwater quality monitoring points to help ensure that representative samples of groundwater can be obtained. Within the guidance consideration is given to:a) the impact of installation materials on the environment;b) the impact of the installation on sample integrity;c) the impact of the environment on the installation and the materials used in its construction.These guidelines allow the impacts to be considered and accounted for when designing a groundwater sampling programme. They also allow an informed assessment of data and results obtained from existing installa