Monitoring Groundwater is that part of underground water which completely fills earth crust spaces and whose flow is nearly exclusively influenced by gravitation force. It arises mainly by infiltration of precipitations and bank filtration. Long-run monitoring of groundwater quantity and groundwater quality is the main objective of sustainable gentle groundwater management in drinking-water installations and in recultivation activities of open pits. Furthermore, Groundwater monitoring is necessary for conservation of evidence and succesful remediation of groundwater contaminations. Groundwater monitoring includes the measurement of groundwater level within the groundwater monitoring network, data transmission and plausibility check of recorded data and the periodical sampling and analyzing of groundwater. The recorded measuring data are primary data to generate hydrographic curves, groundwater contour lines and statistics and to develop groundwater flow models and transport models.