Gas Migration in EBS and Geosphere (GMT) - Construction of the Engineered Barrier System

Construction steps

Emplacement of Bentonite/Sand material

Construction of concrete silo

Concrete silo base

Concrete silo re-inforcement

Emplacement in the annulus

Top concrete silo forms

Top concrete silo instrumentation overview


In all some 210 instruments have been placed within the EBS and backfill including 96 piezometers (internal and external), 10 temperature sensors, 11 total pressure cells and 70 Time Domain Reflectometers (TDRs) to measure water content (and hence saturation) of the EBS. Also included are gas samplers and novel fibre optic measuring systems.

Side Elevation showing Instrumentation

Level 8 (Concrete silo and sand/bentonite)


Horizontal TDR

Pressure and humidity sensors

Instrumentation of Level 2

Instrumentation as built

Instrumentation of top Level


The GTS underground facilities are also available to interested 3rd parties for underground testing and research. The GTS offers cost-effective access to a fully developed, well characterised underground research facility with round the year logistical support - please contact Dr. Ingo Blechschmidt, Head of the Grimsel Test Site, for further details.