Currently, fibre optic sensors are under in-situ investigation by DBE TECHNOLOGY in a sedimentary environment (Konrad mine) and in a salt environment (Morsleben) in Germany. Here at the GTS, fibre optic sensors have been installed in the sand/bentonite buffer and backfill of the Gas Migration Test (GMT). Two humidity sensors and one total pressure cell are installed in the sand/bentonite buffer (Layer12). Two temperature sensors, a humidity sensor and temperature sensor are installed in the backfill (Layer13 : sand layer).

Vertical cross-section of the GMT engineered barrier system

Location of senders

	Photo of pore water pressure, temperature and humidity sensors installed in the backfill (Layer13)
	Photo of total pressure cell and humidity sensor installed in sand/bentonite buffer (Layer12)