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The paper describes a complex project of flow rate measurement applied for groundwater discharge into a tunnel, for both individual seepage points and the collection channel totalizing the flow. Various standard methods are used according to a large range of flow rate magnitudes (tipping bucket, danaid, V-shaped weir) with partial improvements and technical adaptations. Data collection is provided by individual measurement units with ethernet interface sending data to a database server through the internet. Experience of 10 years with several upgrades of either individual measurement or the electronic collection and transmission system is summarized.

Studying the behavior of the rock mass is essential for developing a geophysical monitoring system, which allows continuous timelapse monitoring of the state of the rocks environment. For example, rock mass monitoring might be a crucial part of a system for storing dangerous, especially nuclear waste in a geological environment. The goal of this project is developing a working system for long-term timelapse monitoring of a geological environment using non-destructive geophysical techniques. The monitoring system works with geoelectrical and seismic properties of the hard-rocks environment. The system carries out 4D monitoring of the rock properties behavior in the close vicinity of an underground excavation. For the initial experimental measurements, two geophysical methods were chosen - electrical resistive tomography (ERT) and ultrasonic microseismic. The ERT method uses a set of 48 stainless electrodes 20 cm apart (9.4 m length of the profile in total) and the frequency of the measurements is six hours (i.e., four measurements per day). Currently the seismic uses frequency of five minutes between gathering one seismic record. Attention is paid to the behavior of a significant fracture located in the middle of the measuring system. The monitoring device collects data that are being sent via the LAN connection to the project members' computers. [ABSTRACT FROM AUTHOR]