Project Case Studies

EDF Energy is building the UK’s first EPR nuclear power station in Somerset, which will generate 3.2 GW of electricity. The initial programme of site activity is focusing on earth excavation.

Over 5.5 million m3 of material will be dug from the site, creating excavations large enough to host the foundations for the power station’s two reactors.

The earthworks are intricate, and the digging area has been split into more than 50 separate zones, each of which has a different platform level that must be constructed to and which will become the formation level for the main works package.

Adding to the complexity of the project is the nature of the bedrock on the site: fissured mudstone interbedded with limestone. Maxwell GeoSystems was brought into the project to enable the monitoring of the walls of the tied back excavation of this bedrock in real-time, to identify any movements which may occur during and after the excavation progress.

The MissionOS system dynamically combines data from different sources so that changes in site conditions such as wall movements, and increases in water levels, can be easily displayed.

MissionOS has flexible views which incorporate graphs, contours and a powerful real time 3D viewer of the excavation site. In the event of an instrument exceeding an alarm level, notifications are sent out to key personnel via email/SMS, and an exclusion zone quickly established to protect the workforce.

The enormous size of the site (500x600m) comprising excavations up to 35m deep in bedrock, with more than 100,000m2 of rock slopes to be formed) necessitates a high density of instruments installed.

The latest enhancement is integration of MissionOS with the corporate web GIS – providing site-wide access to instrument readings and alarm status, combined with a wealth of other departmental information.