Groundwater quality historical data

This file contains groundwater quality data compiled from multiple sources. It is impossible to know if this data have been QC/QAed in the past and if it followed data quality evaluation and verification standards. There was no information on the sampling methods nor on the laboratorial protocols used to measure the sampled parameters and the parameters nomenclature varied from source to source and the same parameter may have different corresponding names, or the same name may be associated with a parameter that was collected and measured under multiple protocols. The data have been as cleaned up as possible, nonetheless the quality of the data cannot be ensured and the user must take into consideration that the data variability reflects at least different sampling and measuring methodologies.